Who Said Heat Pumps Don't Work With Small Radiators?

[@danielprescott2552]

It's great to see some quality fact based videos going up around heatpumps. I love the content that you produce, and the fact it's all explained and designed not just thrown in, and then the detail is shared is great. You are doing some great work with unpicking the rubbish going around about heatpumps that is in the media at the moment. I'm an electrical engineer by profession, so not really into heating/mechanical systems in a big way but I can apprecaite the time that is spent doing the calcs to make sure the system is correctly designed. I even put in some underfloor heating recently when we did our downstairs floor thanks to some of your videos. Keep up the great videos.

[@jezlawrence720]

I think what you said at the end is key: you still need to do the calculations. If the radiators are capable of heating the property at the max output of the heatpump or below, *it will work*. It just wont get as good a COP. But you can totally fit one, and then start replacing the radiators or putting in underfloor heating and lowering the general flow temp once you hit the tipping point. My current gas boiler is condensing but from 2007. Serviced every year, still working great. Last two years ive been tracking how low i can get the flow rate against our side temps and identified that several radiators have issues or are undersized. Got a heat loss survey this year (from a heat geek) which confirmed that i *needed* to replace two radiators (which id identified) as they were undersized even for 70c, but the rest are basically fine for 55c down to -3, and some are ok for 50c. None are really ok for 45 or below at -3, though theyre all fine at 5+. Meaning: i need to replace a couple of rads even with the current boiler so i can reliably run it at lower temps all winter and cut my emissions and costs, but can be confident that if the boiler suddenly dies and i have to get a heat pump before im properly ready (or it happens after 2025), i can do that, and itll be fine with good cop most of the winter and expensive in cold snaps, which i can live with, as i already have solar, battery, tank and diverter, which will help, thats why i got those first. I want to get air to air anyway, ideally - so again, targeting the rads choking my whole system efficiency buys me time to save for that and hopefully see a grant come in for those not just wet systems. All of which is to say: thanks for confirming what all my hard work was suggesting to me with this video! As a non expert its incredibly hard to navigate, channels like this have been a godsend for knowing what to look into and how to plan for this - thank you.

[@jamesdcuk]

I appreciate these videos. It’s really helpful to make a judgement from the experience of somebody who has lived with the system. Thanks for putting the work in!

[@seanjay886]

Heat pumps are showing the lack of skills in the domestic market. You can’t over power a bad system design and commission like you could with a gas boiler. You need to know your systems and how to design one. The industry is massively lacking these skills. It’s rare to see such an installer like your self who does know how to design a system and also be upfront if a customer on its shortfalls when it’s a phased project

[@lua-nya]

Even on a (condensing) gas boiler you can save a bunch by commissioning properly.

[@kevfquinn]

Great to see a less-than-ideal situation; ideal situations are easy, we need to deal with the non-ideal homes! Interesting to see the response on hydrogen for domestic heating being so timid - I'd have slated it unequivocally :)

[@N570Z]

Another quality installation and satisfied client. Well done!

[@UrbanPlumbers]

Thanks Stephen. Hope all is well with you.

[@AltoEnergyLimited]

Great to hear the feedback from your customer. He'll definitely see an improvement with the underfloor heating!

[@niconico2900]

We got one of these units as well since february (different country, 7kW model and floor heating + convector combi) and so far the unit has been amazing. We are obviously getting abit higher efficiency but I'm amazed by how well this seems to work on those single panel radiators. We had them too but replaced them. I have one questions: How is the system setup right now? I assume a higher curve but did you also make adjustments to the minimum and maximum temperatures? Im really curious on how this system was dialed in to make this happen.

[@bjjcjc]

Fantastic informative content. As per previous, videos showing installation in less than ideal conditions are useful. We are in a 3 bed detached built in 2000, insulation levels are very good but we are stuck with 10mm microbore to radiators feeding off 22mm flow and return. Is there any way you can make heat pumps work with micro bore or would any installation need to see microbore ripped out?

[@Kwirks]

I have solar panels that I don't get any fit payments back from, I had an IBoost installed & that usually means I don't need the boiler to generate bathing/washing water even in the winter as long it's not cloudy. I did get a new gas boiler fitted to replace a 20yr old GlowWorm non condensing for a Vaillant ecofit pure. I'm now thinking with all our double radiators that are maybe 3yrs old now would be suited better to a heatpump in the rear garden would be much more efficient & effective at keeping the house warm all day rather than the 3 to 4hrs per day with the gas boiler. Great videos keep them coming. Shame you aren't in Yorkshire Urban Plumber. thanks.

[@brianwood5220]

Another great Heat Geek install. Thanks for sharing.

[@philipbroggio9315]

4 bed detached 128m². Installed 7kW Daikin Altherma in June. 11 rads replaced plus new cylinder. Cost £6k. COP to date 3.6 heating and 2.3 DHW. Ave use in Dec 20kWh Heat and 4 kWh DHW. Designed for 50⁰flow@-2⁰ext but in Dec had to turn the system down as too hot. Now use 50⁰@-15⁰ext/28⁰@18⁰ext which maintains 20-21⁰ downstairs and 19⁰ upstairs. 🤓

[@UrbanPlumbers]

good result and a very low price!

[@philipbroggio9315]

​@@UrbanPlumbers Well it was £11k less £5k grant .

[@UrbanPlumbers]

@@philipbroggio9315 very cheap

[@Allegedly2right]

My house is 125m2 I wish I knew how to put that squared 2 up that’s another storey. 17KW Aerona3 and that 3 haha MCS accredited company they did all the work I know it isn’t right but what do you do Stuck with it Dynamis thank you.Just a sore point I know but if you don’t complain they think you are Happy.Cheers

[@philipbroggio9315]

@@Allegedly2right Type 2 but hold finger on key and you get ² ³ etc ⅔ 🤓

[@MarkGaudie]

This system will be so much better when the home owner Patrick installs his UFH system. We love our Valliant Aerotherm 7kW heat pump. Our COP is 3.5 at the min. With existing radiators from the old combi gas boiler heating system.

[@UrbanPlumbers]

he should be able to design it to 35C and have scop of well over 4.

[@Timberjagi]

just wondering. we are looking between a SPRsun heatpump or Vailliant heatpump and using a buffertank with a warm water coil in there or 2 tanks, one for warm water and one for buffer. we did several price requests but its going from only need of a warmwater tank to needing a minimal 500 liter buffertank with warmwater coil otherwise we would get issue's with the heatpump. (i'n in the Netherlands and lost a bit where to make my choice. (we have floorheating on 1st and second floor and low temperature radiators on the 3th floor (our current boiler is set to 40 degrees)

[@normanboyes4983]

Very encouraging story.😀👍 Just for reference what was the actual flow temp at -2C?

[@johnfreshwater3790]

I am not surprised at all as everyone told me I was mad installing an ashp in my property as it is a 200 year old solid stone property 200 square metres. But I was confident it would work so I had one installed and hey presto it's far cheaper than the oil boiler and more comfortable we have the house at a constant 20 degrees or there abouts and the heat pump has a meter on it and it has used 2000 kwh so far this year. I have a friend who has a 70s house and his gas bill was 1300 quid for 3 months of winter. I get around a cop of 4. I have no idea if 2000 kwh is good but it's cheaper than the oil

[@bigjd2k]

Does the solar diverter supply the heat pump compressor, or an immersion heater?

[@mgbroadsterJ]

Is it possible to have the radiators on weather comp and ufh on a stat . Ive found weather comp isn't proactive enough .

[@modo613]

Would setting cylinder temp at say 65 degrees during off peak tarrif rate not solve the lack of hot water issue? Presumably a modern tank would then keep that temp for most of the day?

[@UrbanPlumbers]

Not such an issue now with a solar diverter. It can also be programmer for off peak boost if needed.

[@justinklrjms]

What do you think of the Viessmann heat pumps? From my understanding they ggenerate a higher water temp than most heat pumps.

[@doncoombez]

Great channel, and great content mate. So useful, I'm in a detached 70's house and with an old boiler, I do not want to replace it with a new one. I've already got solar, battery, share of a ripple energy wind farm (check it out, v cool lower cost and green energy), and a brand new unvented cylinder Eventually we will remodel the downstairs, with underfloor and upstairs will stay the same, so this gives me the kind of steer I've been looking for! If only you guys covered hampshire!

[@UrbanPlumbers]

We do cover Hampshire

[@doncoombez]

@@UrbanPlumbers oh that is good to know! I’ll be in touch!

[@maplin007]

I install underfloor heating, have done for 20 years and I must say I don't hear many people raving how cheap their heat pump is to run nor that it always keeps the house warm. My friend in Canada uses a heat pump that runs air conditioning units around the house for heat and cooling , they don't use them for to supply hot water.

[@UrbanPlumbers]

On UFH you can design the system to run at max flow temp of 30-35c which can be amazingly cheap to run. In not sure about your price ratio of electricity to gas where you are though.

[@maplin007]

@@UrbanPlumbers Yes that's the target but I rarely see it achieved and the pump temp has to be raised in the end . Maybe its poor design (pump output in winter vs summer) and in old houses lack of insulation but I see it a lot in new houses too. Heat pumps require pipe centres of 150mm we are told, they are now talking about pipe at 100mm centres, surely if you double the amount of pipe from the normal 200mm you double the amount of water to be heated by the pump? we use to put the pipe at 300mm centres back in the day worked fine, water at 45 degrees, what advantage does more pipe give Heat pumps other than quicker heat transfer potentially? No idea I'm in the UK and the gas and electric pricing are linked. It is more efficient I'm told to heat water with a gas boiler (95%) than to produce electric with gas (50%) the answer I guess will be cheaper energy, which we used to have.

[@UrbanPlumbers]

Pipe sizing will depend on the heat loss per m2. Usually 150mm is absolutely fine with HP, with 100mm and screed you can design to below 35c in new builds and have 4.5 cop which will be way cheaper to run than gas. It’s really not that difficult to beat gas running cost and have better home heating (always on!) and better comfort - as long as you design the system well

[@maplin007]

@@UrbanPlumbersI see so 35c only at 100mm, so that means almost double the cost of the Underfloor and an expensive heat pump . For most people it would have to be very cheap to run to claw that money back. I keep hearing "as long as you design the system well" what does that entail? Presumably every new house reaches the insulation standards and The underfloor heating's in at 100mm. What variables are there to size the Heat pump? heat loss per m2 you've mentioned.

[@UrbanPlumbers]

@@maplin007 no, you can run 30-35c even with 300mm spacing provided your heat loss per m2 allows that. Good design is: - calculate or measure property heat loss first and be as accurate as possible - size the unit for as close to the 100% property load as possible to avoid cycling in the shoulder months - avoid micro zoning or zoning altogether to extend the system run times - fully weather-compensated systems do not require zoning anyway - make sure you use proper weather-compensated controls and set them up correctly - size your emitters or UFH correctly to the room heat loss for even heat distribution - to avoid overheating certain areas - if you have to zone (solar gain) - use temperature limiters not thermostats - just to close small areas off if needed - size you pump to the system flow / DT - size your pipework for correct velocity - this is key with heat pumps - if your system is too large for a single circulator - use buffers, but avoid them if you do not need them as they can create distortion and lower the efficiency of the system - check you have sufficient system volume for your application - if not add a volumizer - but do not add one if you do not need it - commission the setup correctly checking your flow rates, heat curves, etc... This is just scratching the surface of the system design. If you are interested in this stuff check out Heat Geek Heating Mastery course.

[@lokkytub3]

What were the flow and room temps incl set back temp and were they altered during this period?

[@UrbanPlumbers]

Room temps 21c, flow temp at design was changing due to auto adapt heat curve - but around 40c.

[@endatheworld]

Cop 2 was my guess at the beginning. ….happy to be proved wrong!

[@colingoode3702]

I realise that in this example the homeowner had future plans that meant spending money on rad changes was not a priority for him. However, for most straight boiler to air to water heat pump swaps radiators aren't the real issue because if required single rads can be changed fairly easily & cost effectively for finned doubles or even fan convectors (if there is a power outlet nearby). The real issue is the size of the existing heating pipes & flow rates. My house (built in 1986) has a 10mm microbore Y plan system that relies on the higher temperatures & TD's from a gas boiler & lower flow rates via 10mm pipes. To replace all or most of the 10mm pipework for 15mm all the 1st floor, the chipboard floors & carpets would need to come up & the ground floor dot & dab walls chased out to accommodate the larger 15mm pipework. This would simply not be financially viable, would create a huge mess & probably require us to move out of the house for a period of time while the work was being done. Instead I intend to go for an Air to Air heat pump system with a separate Heat Pump cylinder for the hot water. Apart from being much cheaper than Air to Water, an Air to Air heat pump system can provide cooling in summer as well. This will enable me to ditch my gas supply all together & remove all the radiators. Some rads (e.g. bathroom & toilets) will be replaced with electric oil filled towel rail type convector heaters since these rooms will not be served by the A2A system. It's work in progress because we are just about to have a solar & battery system installed so finances can only stretch so far at any one time. I'm considering a Multi or mini VRF air to air system some of which can now include HW heating. However, unless someone can convince me otherwise I think I prefer a totally separate Heat Pump hot water tank solution. Time will tell. This was a good video & shows not only why every installation is different in terms of the physical aspects of the building but, also what future plans the homeowner has which can also affect the route & type of system that is chosen. This is why it is essential to have a qualified & knowledgeable installer who does the calcs, goes the extra mile & understands what is required rather than the cowboys that have a "one size fits all" solution that gets thrown in for the lowest possible cost & then disappear into the sunset never to be seen again.

[@jasonprice8158]

same situation here, 90’s house with microbore throughout and single panel radiators. I run boiler at 55degC but not sure I could get down to the heat pump temps for good efficiency 🙂

[@tedwaine5544]

I am also considering air to air heat pump as my 60s house has no radiators but ducting for warm air heating instead. However, so far using google it seems there are very few experienced installers / suppliers in the UK as air-to-air is a very unusual choice here .... have you found anyone who specialises in air-to-air? If you don't mind sharing I'd be grateful.

[@colingoode3702]

@@tedwaine5544 There are loads of Air to Air Heat Pump installers in the UK because A2A Heat Pump systems are widely used for commercial Air Con systems as well as domestic houses. A2A systems cool, heat & filter air by reversing their operation for summer / winter. Air to Water systems are heating only. The trick is to find a local Air Conditioning company that has a good track record & installation experience with domestic house installations which pose a different set of challenges than commercial buildings. Domestic installations take more time to install & you have to be more sensitive to the homeowners requirements, limited power supply issues, tidy & neat workmanship, knowledge about the maximum permitted external sound levels for outdoor units in relation to neighbours etc. If you have existing ducting to all rooms then it might be possible to utilise it for a ducted split heat pump system to replace your warm air furnace - if it has a fan. It depends on the duct sizes & other factors & it may not be possible to have independent temperature control in each room without adding more complex damper controls. Someone will need to do a survey to advise further. I use to be in the refrigeration & AC business for 48 years (retired now). I worked for manufacturers as a product manager, distributors & installation companies. We did quite a few domestic installations - maily conservatories & home offices. Since then whole house cooling / heating Heat Pump systems have become more popular. You need to Google Air Conditioning or Domestic Air Conditioning installers for your area & see what comes up. Don't search for plumbers or heating engineers because they will normally only deal with Air to Water HP systems. Despite what many people say the heating / plumbing & air conditioning industry skill sets are very different. Then look at the individual company websites for info on any domestic installations they may have done. Some companies specialise in domestic installations so you need to seek them out. Ask to see their qualifications, industry affiliations, F-Gas certificates etc. Some of this may be displayed on their websites. If they cannot offer you a valid F-Gas registration certificate walk away. If they do have a F-Gas certification it can be checked on the relevant certification website, e.g. REFCOM. It's a similar system to that of GAS SAFE (old Corgi) system for gas engineers & certifies them or their engineers are allowed to use & handle F-Gas refrigerants. Get a few quotes & compare. Like most industries there are cowboys in the AC industry. Every day I see pictures of poor & dangerous installations posted on LinkedIn & other such sites so be aware & ask them for references you could contact to backup their claims. Ask the companies that come to survey your house as many questions as possible & see how they respond. If any of them try to quote by asking questions & not visiting the house walk away because it is impossible to provide an accurate quote without seeing the house & checking room sizes, building orientation (could do from Google maps), pipe routes, power supplies etc etc. Some may give you a ballpark figure to test your budget expectations but the only way to do an accurate quote is to visit the property. The good companies will not charge for a site survey. The companies that offer different solutions or more than one manufacturer as options are working harder for your business. Don't accept quotes that offer unknown makes of air con equipment which may not have proper UK back up or spare parts. Again Google the makes of equipment offered to see who they are or ask what makes they offer. The main manufacturers for domestic house equipment are Daikin, Fujitsu, Mitsubishi, Toshiba, Hitachi, LG, Samsung, Panasonic etc. Last but not least the cheapest price is probably not the best solution. To install a domestic A2A Heat Pump system properly & neatly takes time & experience. Have a look at the channel links below both of which chose Toshiba A2A systems specifically because of the style of the indoor wall mounted units which can be a major influence on what make you decide on. They have also documented their solar systems & EV cars on their channels. Tim & Kats Green Walk are in the Cotswolds & The EV Puzzle guy is I believe in Norfolk. I'm sure there are other people on YT who have done similar videos. Good luck with your search. www.youtube.com/@TimAndKatsGreenWalk kzbin.info/www/bejne/mJfGoWurhq6ApKM

[@tedwaine5544]

@@colingoode3702 Thank you very much for your detailed reply, much appreciated. This is all new information to me and really useful. I was certainly looking in the wrong direction with my initial searches. All the best.

[@colingoode3702]

@@jasonprice8158 I've got my boiler running at 55c also. It does the hot water tank (set to 50c) as well as the rads (system boiler not a combi). It works OK but I can't lower the flow temp much further since that will drop the stored HW temp & some of the rads would struggle. I have a mixture of single, doubles & finned rads & all are now fitted with Tado Smart Rad valves for individual room schedule & control. Some unused rooms are set to 10c frost protection 24/7. All this will become redundant if I go for the A2A HP system. Lottery win needed first I think!!

[@simonloker8334]

hi i noticed you didnt use the buffer or volumiser. I am wanting my plumber to fit a Grant 6k HP and a Mitsubishi 210 cylinder with all the fittings attached, 3 bed open plan downstairs, to the radiators. My question is what figures do i need to make sure we don't destroy the tank. both HP and cylinder. as both say can be used without buffers. looking for a low flow 40c at first. is there anything i can try with my boiler to find out as only got the one in the boiler. keep fitting the heat pump fight!

[@pumpkinhead456]

3... Oh, yay! If you'd like to prove they work in big Victorian houses, and would enjoy a trip to Scotland, I'm looking for someone to hook up a 12kw Vaillant - essentially plug and play, as all the controls, tank, low loss etc already in :)

[@russellcole8682]

What refrigerant does the heat pump use?

[@UrbanPlumbers]

R290

[@henrikgrunditz2672]

What size house was this? 3 bedroom mid terrace? Assume insulation was also good standard?

[@UrbanPlumbers]

3 bed terrace, no new insulation, existing windows. Average standard

[@JWildOnes]

What was his radiator flow temperature at DoT?

[@UrbanPlumbers]

38c

[@B0jangle5]

2.9 was my guess. Out of interest, what cylinder did you install? I'm looking at putting one in my loft and thinking that I may need to enlarge the hatch.

[@UrbanPlumbers]

It’s a joule cylinder. You can get slim line Heat Pump cylinder that is only 470mm wide

[@gpbeck]

Installing underfloor properly with screed has a much higher carbon footprint than a few radiator swaps. Also turning off overnight - is energy saved greater than that needed to rewarm every day with small rads?

[@audrunasgruslys9243]

Turning off overnight is not a great idea as far as condensation is concerned. But as heat pump efficiency depend on outside temperature (the lower the worse) ir may make economical sense to turn off at night and reheat when the weather gets wormer during day time.

[@edc1569]

Eddi seems like a bit of a hack, would be nice if the Vaillant controller would be aware of the export and boost the cylinder temperature to capture some of that excess, even running a heat-pump with a CoP of < 2 is still a lot better than an electric element. The software has some catching up to do. I'd like to see a system where you capture heat energy into a large thermal store based on electricity pricing and solar availability, then draw down that store for space or water heating - I suppose it's possible just need a bit of space!

[@UrbanPlumbers]

the excess power though may be too much in the summer anway, so I would rather use eddie than fire the heat pump.

[@modo613]

Could be the fact that excess solar is highly intermittent. Probably not a good idea to fire up the heat pump for 2 minutes in between clouds! But an electric element can transfer any reasonable amount of energy into the water, on and off without issue.

[@TC-V8]

​@M Wittler agree if you only have solar, but if you had a battery as well, the heatpump would run of the battery, with the panels topping up.

[@arpa592]

Eddi does the same thing what most modern Hybrid solar inverter capable of. Diverting excess power, as opposed to send it back to the grid. It's not about what method is more efficient to heat the water, it is about to utilize the generated power from the PV system. Power companies pay close to nothing for the exported power so if we take this into the account, this is still a good deal. Extra benefit of Eddi, the topup or boost option on low tariff period if needed. I have a similar unit, Catchpower which pretty much the same from a different manufacturer. Only thing what I would add to mine, I'm not sure if Eddi has that function or not, to have different target temperature during the sunnier months to store more energy in when excess available (I change setpoints manually at the moment).

[@UrbanPlumbers]

I think a smart Tesla immersion can do it, Eddie doesn’t know the temperature in the cylinder

[@asabriggs6426]

Good job, nice to see your expectations were exceeded by a good margin! What's the design flow temperature, peak demand and heat curve of the setup?

[@UrbanPlumbers]

design for the current rads has to be 55C, but it will be around 35C for the UFH. Peak demand is 4.5kW, heat curve not sure what it is at the moment.

[@asabriggs6426]

​@@UrbanPlumbers Right at the limit of what is MCS compliant :-) @ElectricVehicleMan reported on his Arotherm Plus performance, and DHW came out at a COP of 2.8 over the winter, so similar to this (of course lower because he's from the North, plus DHW runs at a constant high temperature rather than weather compensated central heating). Thanks for taking the time to document the performance!

[@UrbanPlumbers]

@@asabriggs6426 I expect this system to run above 4 once the UFH goes in.

[@PatTowey]

Heat curve is currently at 0.45 and seems to be working ok!

[@marcexec]

​@@PatTowey we have very high hot water needs and a small tank, too so we added waste water heat recovery when redoing the bathrooms. We used a Zypho 30 (30% heat recovered) under the bathtub (digital shower) and a Zypho 40 in the ensuite (T90SR power shower). The 40 is nearly too efficient and I would go with a thermostatic or digital shower in the ensuite now as we don't run out any more so no point for the electric backup.

[@davidfellowes1628]

If you had a small apartment, 1 bed with a three radiator water system heated by a 6kW electric heater, which is far too expensive to run and works erratically through a thermostat (basically stop / start), it is too small for a heat pump. What upgrade options are there? Can you help?

[@UrbanPlumbers]

Flats should be on district heating. It’s insanity that most flats have their own boilers really.

[@davidfellowes1628]

@@UrbanPlumbers Thanks. Can that be done in older properties, or just the new builds. I'm concerned about the number of old properties needing to be renovated.

[@UrbanPlumbers]

@@davidfellowes1628 any properties.

[@marcexec]

If you can't get DH, maybe air to air is an option?

[@davidfellowes1628]

@@marcexec We have six blocks each with four by I bedroom apartments. One block stands alone, then two blocks are attached and another three blocks are attached. The dilemma is affordability, as these all-electric apartments were built in the mid 70"s and only a third of residents can afford an upgrade of their heating. This means nothing gets done. You are the only person thinking outside the box.

[@Medea007]

What's the flow temperature? Size of the house?

[@UrbanPlumbers]

2 bed bungalow, designed to 40c if I remember correctly

[@fuzzyreason]

This is impressive. I’m in a modern 5 bedroom house, south west facing. I have a Vaillant 10kw heat pump on a heat curve of 0.45. Two zones, both at 21 degrees, with setback of 19.5. However, my COP is only 2.3. What am I doing wrong?

[@UrbanPlumbers]

do you have any of the following on your system? - more than 1 heating zone - buffer or low loss header - under floor heating manifold with a belnding valve and a pump - more than 1 thermostat - non Vaillant thermostat - underszied pipework between the heat pump and the cylinder (such as 22 or 28mm - both to small for your unit) - plastic pipework with push fit fittings

[@fuzzyreason]

@@UrbanPlumbers I have 2 zones - upstairs/downstairs. I’ve read that this is not so good for ASHP. I also have a buffer tank installed. Two sensotherm thermostats, controlling both zones. Pipe work is plastic and probably 22mm. So, these are what’s limiting the COP?

[@UrbanPlumbers]

Those are the staring points.

[@fuzzyreason]

@@UrbanPlumbers I should have said that pipe work from heat pump to cylinder is more than 28mm, and not plastic. Radiator pipe work is 22mm and plastic. How can make it just one zone? Does pipe work have to be changed? I’ve tried removing zone 2 from sensotherm and it just shows an error.

[@Anthony-dh3ty]

@@UrbanPlumbers Is push fit not suitable for a heat pump?

[@edwardgordonrowlands1126]

Just caught up with this article and pleased to see that the AW heat pump installation wasn't held back by the less-than-ideal radiators when it comes to replacing a gas boiler! However, if the property own is looking to benefit from the £5,000 grant my understanding is that for the installer to obtain the grant, the SCOP of the intended heat pump installation must be at least 2.8 and it must be capable of meeting the full space heating and hot water heating demands of the property. Also, any shortfalls in insulation identified the property's EPC must have been addressed ahead of the heat pump installation. Could you confirm what the situation is on grant eligibility, as without the grant I wouldn't be able to afford the upfront cost.

[@edwardgordonrowlands1126]

"property own" = "property owner"

[@UrbanPlumbers]

Property needs an EPC without outstanding recommendations regarding and you are correct - full CH and DHW needs to be done by the heat pump

[@edwardgordonrowlands1126]

@@UrbanPlumbers Many thanks for your prompt reply. I am interested in having a heat pump installed but only if I am certain the £5,000 grant will be awarded. Does the awarding of a grant also require the efficiency performance of the proposed installation to be at least 2.8 or is it the actual performance after installation that has to be greater than 2.8? If the latter it seems something of a gamble with respect to recieving grant support if there are no changes to existing panel radiators on installing a heat pump - in your video you were expecting 2.5 and fortunately it came out at 3.0. I appreciate your client was going to install underfloor heating and hence the panel radiators will in due course be removed, but that is not an option for my house.

[@UrbanPlumbers]

Don’t do it then. Upgrading rads and pipework for higher flow and lower flow temperature is essential for decent efficiency. Installing a heat pump cheaply onto existing system with high flow temp and low scop is not the best idea.

[@michaeldepodesta001]

​@@UrbanPlumbers Good Morning. Gordon raises a question about the dependence of the government grant on COP, but I can't see how that makes sense. 1. COP varies from hour-to-hour. 2. Most installations don't reliably report COP 3. Actually what matters is seasonal COP - sCOP - and that cannot be assessed in any case until after a heating season - which may be milder or more harsh varying from year to year. Surely for the grant the only thing that can matter is designer's ESTIMATED sCOP? Best wishes: M

[@smithleon]

perhaps I missed it but what were the flow temps of this system?

[@alanmurphy3584]

In comments above, 55° for now but will come down to 35 when UFH goes in

[@sambutler927]

Hi Urban Plumber, What are the Vaillant units like to wire up. I’ve just installed my 1st heat pump which is a Daikin low temp. However I really like Vaillant ? Thanks

[@UrbanPlumbers]

The simplest heat pump to wire ever

[@sambutler927]

Good to know. Might have to jump on a Vaillant course. Thanks

[@A4Avery]

Hi, I really enjoy your videos. I am a engineer who has just completed the heat geek training and looking to install a aerotherm on my own house in the next few weeks. MCS inspection in may. Is there a benefit in using a Eddie over powering the heat pump and getting 3x as much heat from what the Eddie would have given you for hot water when solar production is high?

[@UrbanPlumbers]

yes, there is - in a summer the unit can just sit idle. In the winter, on a sunny day, the unit does not have to start the DHW cycle. Also in small heat loss (small unit such as here - 5kW) and big water use you can combine both 5kW from the HP and 3kW from solar or direct electric to get 8kW into the cylinder. On top of that you can programm Eddie to use cheaper tarrif to charge the cylinder.

[@A4Avery]

@@UrbanPlumbers thanks for the reply. I’m just trying to gather as much information as possible to make sure we can install the systems to the best standards. How are you finding being registered as heat geek elite? Do you get a lot more support to bring your knowledge on and does it generate you much work? Thanks

[@mihaiachim5299]

@ 9:32 you can make a heat pump suitable for any type of home (Nibe boasts that they heated a 1000 sq m mountain cabin in a climate where the temperature easily reaches -25 degrees in winter) but the fact that it is possible does not mean that it is also economically viable (without artificially creating profitability through subsidies paid by the rest of the taxpayers - because someone still pays the difference in money in one form or another) or that it is or will be a better choice than gas heating ...

[@UpsideDownFork]

The magical Arotherm Plus strikes again! Nicely done. I'm guessing no buffer tank?

[@UrbanPlumbers]

No buffer on any of my installs so far, well apart for that first infamous one as a subbie designed by the main contractor

[@jezlawrence720]

Regards the noise issue, its clear that an individual heat pump, properly serviced, is fine. I wonder how it adds up when a whole row or terrace house have them. To be clear i have no idea, im just wondering if anyone knows of any studies. Sound can be wierd when waves overlap.

[@BenIsInSweden]

Anecdotal; but In my town (in Sweden), there's a path I walk down to get to the local shop, which has a row of 6 terraced bungalows opposite a row of 5 terraced bungalows, all with heat pumps beside the front doors. Hardly notice the ones that are on immediately to the left or right, so in unison not really a problem.

[@jezlawrence720]

@@BenIsInSweden I will take anecdotal over supposition, so thank you!

[@samragheb]

Great video. So positive

[@Richardincancale]

Based on one week’s experience with a heat pump I’d guess COP of 3 with 10 type radiators. I’m using 21 type radiators except for one that I upgraded to 22 type. [Edit: My guess was spot-on… I win the internet!!]

[@UrbanPlumbers]

Yep, correct

[@Richardincancale]

@@UrbanPlumbers With my new system I actually measured the COP from first principles: used a contact thermometer to measure the flow and return temperatures, and hence the Delta-T, the flow rate based on the display on the circulator pump in m3/hr and the electricity consumption from the smart meter. After simple arithmetic and the SHC of water and an outside temperature of 8 degrees outside and I got a COP of 4.

[@UrbanPlumbers]

@@Richardincancale that is a pretty decent result

[@neo_265]

Am I missing something regarding the costing? I can buy a Vaillant Arotherm heat pump and cylinder for £6.5k. Are you saying the installation is £6.5k to make it £13k total?

[@davidbriggs8076]

Would have been nice to know exactly what the £25k covered, just materials or labour too. The problem with take up of heat pumps is that a new gas boiler cost is £1200 and if it's just a replacement then cost to customer is not going to exceed £3k with installation

[@UrbanPlumbers]

direct combi swap with labour and installation materials is around £2,500-£3,500 in London and the South. The cost of new boiler and unvented cylinder with system conversion and PDHW and weather compensation is around £5,000-£8,000 (all in) This job costed the client £13,000 in total (labour and materials) and he got £7,000 back in different grants mkaing the end cost of the installation of £6,000 Solar PV and the battery were £12,000

[@davidbriggs8076]

@@UrbanPlumbers that makes more sense

[@john-qq4ym]

Only about one third of the heat energy arrives into your home when converted to electricity. Then we use heat pumps to end up even Stevens. Well, someone made a suggestion on my group "John's Heat pump Development Group " Burn gas to drive a compressor at your home, gather almost 90% of that energy and "Bob's your uncle" I'm replacing my oil boiler, cost about 6.5 pence kwh. My heat pump is about CoP 2.5. and that equates to about 14 pence kwh. I love a good hot bath and 22°c in the evening. Before you get this one in, I wasn't allowed to claim the government grant, MCS will stifle any innovation at improving things yourself!

[@antok1794]

Very informative video, just on the Eddi install, if the Solar PV has excess power lets say 1kw and it diverts through the Edddi, I presume you get 1kw of energy to heat the water (100% efficiency), why not use that 1kw of extra energy and send it to the consumer board thus using the heat pump to heat the hot water and get 300% or better efficiency, if there is any excess solar send it back to the grid and get paid for it. My point is an Eddi worth the extra cost with a heat pump?

[@UrbanPlumbers]

You can have both as well and you getting 1kw extra charging capacity or you can just have heat pump holiday in the summer so that compressor doesn’t have to start at all.

[@edwardgordonrowlands1126]

I assume any PV excess for Eddi is only available after all domestic electrical consumption including the heat pump (I assume this has priority for PV output) has been met? I think Eddi can also control whether battery or hot water gets first priority for any PV excess. I expect PV via Eddi can provide much hotter water via the electrical element in the cylinder than the heat pump can deliver, thus effectively increasing the capacity of the hot water cyclinder at times of increased hot water demand (because more cold water can be used to achieve the required shower / bath water temperature at point of use). Eddi can manage very small PV surpluses down to 200w. We have a condensing gas boiler and unvented hot water cylinder, and a 6.3 kW PV system, the latter installed last December. As we don't have a battery all excess PV first goes to hot water and the remainder is exported. I expect this to save around 2,000 kWh of gas consumption and around 1,500 kWh electricity import over 12 months. Within a year, the plan is to invest in heat pump technology. I'm inclined towards AAHP rather than AWHP, because I could install a split system with one external unit and two internal units, one to cover our living room / dining room area and the other located over the landing area to separately control the first floor temperature, with cooling in the summer months as and when required. We'll continue to use our current condensing gas boiler and then make a decision as to what further heat pump investment is required with respect to heating & hot water and coming off gas altogether.

[@mihaiachim5299]

@ 2:50 it is not so fair to compare the comfort of a classic boiler with 2.5 to 1 modulation that has a minimum power of 10 kw with a heat pump with higher variable power ranges... - obviously for the owner the heat was more uniform with the heat pump (customers who replace their classic boilers with high-modulation condensing boilers tell me the same thing) ... :) . a gas boiler with modulation of 10:1 or higher would have offered the same comfort effect as the heat pump :) at -5, an air conditioner with a start/stop compressor can also make heat :) - not efficient, but it still makes heat without too many problems :) I expect that the boiler with 10:1 modulation that I am going to install will probably be the last gas boiler that I will have - although I hope it won't be like that...

[@arpa592]

I think the consistent temperature, and comfort is a side effect only, beside the environmental benefits....

[@CrazedCrittic]

COE #@3.5 on small rads.. please come and quote for my HP in Wisbech.

[@sergeydanilov]

I think this is almost equivalent to running an electric boiler. Heat pump brings maybe 20% efficiency over the electric boiler and maybe another 20% comes from solar (I didn't do calculations, just my best guess). Electricity is still 4x more expensive than gas per kWh. I can't believe this can be a good deal.

[@UrbanPlumbers]

no its not. That heat pump now uses 25% of the electricty a deirect electric heating would. So it is 4 times cheaper to run. (scop of 4 last witner)

[@sergeydanilov]

@@UrbanPlumbers thanks for the correction Sir. Live and learn every day.

[@easy_s3351]

If the heat pump heats the house just as good as the gas boiler then I wonder what temps the boiler was running at. I'm guessing a temp traject of something like 60C-50C?

[@johntisbury]

Good to see, a good myth buster.

[@Group51]

Holy shit that is my estate! Doesn’t it have concrete floors? Where did the pipes go? Oh. Just re watched. Pipes went right up the wall to the attic? Head spinning. So that means you probably used the solar scaffolding. The low hum noise he mentions sounds like my gas boiler. He’s right about the road, but if that’s the house I’ve seen (I only saw solar) it’s nicely downhill and a bit quieter than the houses backing onto the road.

[@anglefire1965]

Why use an eddi to divert solar to hws at a cop of 1 rather than to the heat pump at a cop of say 2.5 at a higher temperature- or is the heat pump not man enough?

[@UrbanPlumbers]

It is man enough, can go to 75c. Why fire it though in the summer? It can just sit idle most of the year and not use compressor.

[@Umski]

Tend to agree that on balance although it may seem appealing to get the better ratio using the HP for DHW, the Eddi is essentially solid state and with a 6kWp PV system there will be massive excess even after the battery is charged so no point in running the HP - I have 4kWp PV with a 4.8kWh battery and excess diversion on a 210L unvented - today the battery was fully charged by 10.30 and the excess dumped into the tank which then topped out at 70C by around 2pm - I was then exporting again 😢

[@brianholding4357]

3.2?

[@kvaegenbjergvej]

Growatt battery most be in frostfree enviroment, best at 20 C. If under 2 c it wont charge.

[@wobby1516]

I can’t see how hydrogen is the future for home heating, for a start the gas infrastructure just isn’t up to transporting hydrogen. Hydrogen is a very volatile fuel and it molecular structure is tiny. The other reason is the inefficiencies in producing hydrogen. Unless new far cheaper methods are found it just doesn’t make any sense. Electricity is without doubt the future, heat pumps along side resistive heaters are the best way forward, especially if we can generate the electricity from renewables and who know “Nuclear Fusion”, not to be confused with nuclear fission that produces radioactive waste.

[@jamessomying]

Always a good idea to leave the old vertical flue there incase you need it in the future.

[@UrbanPlumbers]

adds ventilation to the roof :) - seriously though there was no access anymore as PV installers covered the whole roof with panels.

[@jamessomying]

@@UrbanPlumbers Ha, yes good old ventilation to the roof, I know what you mean, Iv'e done it a few times, although I had no PV installer excuse to be honest. Nice work mate. Great vids, take care.

[@charliefox6987]

Great vid as usual! With the rollout of heat pumps do you think it’s still worth it becoming a gas engineer? I’ve put down a deposit for a course but I’m in two minds !! Be great to hear your feedback 👍

[@UrbanPlumbers]

Not worth it. Go straight into renewables. You only need a gas ticket for capping the meters of. Not to mention that gas course will not teach you much unless you do a plumbing qualification as well.

[@phobos.289]

I disagree. Loads of money to be made with gas, Charlie. Get your head around gas central heating first. Will be easier if you then want to transition to renewables

[@UrbanPlumbers]

There is so much work with renewables that he will be better od with clear focus on one thing. He can do gas qualifications as well, but they are no longer necessary.

[@UrbanPlumbers]

It may actually be bette to do f gas instead and fully concentrate on heat pumps, split units and air to air. That is were the market is going to go.

[@charliefox6987]

Thanks guys I appreciate the feedback 👍👍

[@voyt5729]

25k for a heat pump and solar instead of 2k for combi boiler...

[@BogdanDumiter]

3.0 Cop ?

[@UrbanPlumbers]

very good!

[@BogdanDumiter]

Why I don't always get precisely, is about the real consumption of the whole HP. They usually only show the compressor/inverter consumption, without counting the fan and recirculating pump consumptions.

[@sip5574]

Just starting video, I recon CoP of 1.7.

[@OKuusava]

I'd just forget the floor-heating, just change the radiators on twins.

[@patrickpowers5995]

Of course they do but running cost and efficiency are NOT the real issue. The real issue is simple: ordinary radiators already installed are designed to emit the necessary heat for the room only when the water temperature is much higher. Heat pumps do not produce water at such temperatures so they do not provide the same heat output.

[@UrbanPlumbers]

The issue is really, most radiators have been window sized and not designed hence giving random results

[@ianmilleris]

Training a summer fan at a radiator will greatly increase the amount of heat convected into a room.

[@UrbanPlumbers]

that is true.

[@flaviusvirlan3406]

5kw heat pump ? so the house only needs 5kw to warm up ?

[@UrbanPlumbers]

Less than that. Around 4kw actually

[@flaviusvirlan3406]

@@UrbanPlumbers i thought you calculate the volume of one room and u multiply it by 50w/m3 .. am i wrong ?

[@replevideo6096]

So it works out about the same as gas, but now the hot water is supplied by solar panels and a storage battery, not by the heat pump. The fact that the radiators are adequate is probably because they were bigger than needed before. Heating engineers do make mistakes. You do not mention the positioning of the flat, but if a flat has other flats adjoining above and to both sides which are also heated to 20 degrees, the flat would not need much heat input because there is no heat loss through the walls and ceiling. I knew someone with a flat like that, and their gas bill was minuscule.

[@UrbanPlumbers]

It’s a house

[@replevideo6096]

@@UrbanPlumbers Yes, I think I confused it with something I was watching earlier. Anyway, as this house already has a solar array that was designed to provide excess power to cash in on selling power to the grid, and with battery storage, it is likely that the insulation has been upgraded considerably too. Someone has rigged up this house already with no expenses spared. I have watched many videos on the subject and the ones where bills went up greatly outnumber those where savings were made. I also have suspicions that some of them are actually actors paid by the industry or green think tanks to promote heat pumps. Some of them gush praise on their supposed heat pump installation to the extent it sounds too good to be true, and it probably is.

[@UrbanPlumbers]

No upgrades to insulation or windows have been made apart for loft insulation. They are my clients to paid actors.

[@PatTowey]

​@@replevideo6096 don't really know what you mean by 'rigged up this house, no expense spared'. We bought it 6 months ago, it had an EPC of C and all we did before the heat pump went in was slightly improve the loft insulation and put in the solar panels. There is no catch here; I was happy to answer questions to share our experience and show how heat pumps can work in houses like this, in part to counter the plethora of narratives in the media of people ripping out incorrectly sized and incorrectly installed heat pumps. If done well, they work and can be better than gas boilers.

[@replevideo6096]

@@PatTowey You did not say if you installed the solar panels and battery system or if they were already in place when you bought the house. From what I gather the heat pump takes no part in supplying hot water because that is taken care of by the solar panel set up. So the heat pump is just for heating the house. A previous owner of the house has obviously spared no expense, and may have even installed extra insulation which you are unaware of, which would explain why you did not need larger radiators. Really my point was that yours is not a typical example.

[@jezzaandrews1940]

An Air to water heat pump installed by a very diligent heat geek trained installer and still there isnt adequate hot water!! There is a fine line on the tolerances on these systems! Lets just admit they arent as good as modern gas and oil hot water priority boilers! They are getting there, but give it 10 years or so, before they will be fit and forget or something better crops up. This from someone who bought a betamax player😀

[@UrbanPlumbers]

it's not the technology. Its about efficiency. They can easily rise the temperature on the cylidner from 50 to 60 - the unit can do that, it is just inefficient. They also could not get a bigger cylinder, as there was no space in the loft for it due to the raised floor with 300mm insulation. The tech is already here and it works great.

[@jezzaandrews1940]

@@UrbanPlumbers So effeciency over practicality? I'm not knocking you, coz if I was looking for someone to fit one, I would want someone like you to do it. But If I spend thousands and thousands of pounds on an all singing all dancing 21st Century heat pump, I want it to at least perform as good or better than my 19th century technology gas boiler. You never run out of hot water, with a combi or hot water priority boiler. The future might be heat pumps, who knows? Only time will tell! I'll await the revolution and watch all the guinea pigs fit them, until I'm forced to! Though I think I might get an air to air system for the summer and see how it performs next winter on heat.😉

[@paulstevens5329]

So what I got from that was….standard efficiency boiler was comparable to a heat pump New condensing gas boiler would be more efficient.

[@MickeyBlue-eyes]

It uses the same energy as a NON condensing gas boiler, which is not an efficient boiler. Plus, all the weight in the loft 😱. 25k is a lot of gas. At £30 per week (in winter months) thats roughly 16 years to break even.

[@UrbanPlumbers]

No, it’s using around 3.6 less energy

[@Anthony-dh3ty]

The maths is still not adding up on heat pumps. Surely a weather compensated Viessmann or Vaillant system boiler works out much cheaper for customers and with PDHW sounds like a better system considering he is running out of hot water here. At this moment in time it seems it only makes sense to get a heat pump if you are interested in saving the planet

[@UrbanPlumbers]

Good gas set up can only be around 93-94% efficient at best, meaning that a heat pump with a scop of 3.4 or above is still cheaper to run plus you can use solar or battery to run a heat pump. Well designed and installed system with a modern heat pump in our climate will always beat even the best gas boiler.

[@Anthony-dh3ty]

@@UrbanPlumbers If heat pumps became mainstram it would be a disaster, imagine the combi slinging monkey installers and builders/architects trying to size heat pumps correctly, cold houses and no hot water or sky high electricity bills. I think there is a long way to go!

[@UrbanPlumbers]

@@Anthony-dh3ty exactly this is already happening all over the place, especially on new builds. We need to train installers properly - this is what Heat Geek is already doing.

[@UsernameTm]

Guys just said the heat pump is costing the same amount in energy as a gas boiler,

[@UrbanPlumbers]

On very high flow temp and old radiators. When UFH is installed it will cost much less. Even now it’s actually cheaper to run than a gas boiler that is to solar pv

[@richardkingadi5511]

£25k ? Yikes - Expensive hobby ! Way beyond my means. I'll battle on, trying to find all the airleaks left by Mr Bodge the Builder when the house was built, way back in 2003!

[@Etacovda63]

25k with the solar and batteries

[@taffiejames1496]

​@Etacovda63 still VERY expensive

[@richardkingadi5511]

@@taffiejames1496 But you have the satisfaction of knowing you are saving the world... ;)

[@djdimma]

Let's go heat pumps ❤❤

[@simfoo]

My guess would be a cop of 2-2.5 if the water is heated to ~60 degrees

[@simfoo]

Ok 3.1 is surprisingly high for this house

[@UrbanPlumbers]

I know. It surprised me as well

[@gary_thepropertyexpert]

@@UrbanPlumbers what was the flow temp for rads please?

[@andymav3023]

It’s a nice idea guys but most of us don’t have have that kind of money laying about

[@xyz5703]

Er... this is not good. Just because it's better than using the old gas boiler previously it's still not very efficient. I'd cry if I spent that much on heating. 🙁

[@UrbanPlumbers]

It now costs the owner probably nothing to run as he has solar, battery and cheaper tariff.

[@alexpapp483]

What about burning gas to generate electricity? Which from my understanding, is the fuel that is used most for generating electricity. Your house might be more eco friendly with a heat pump but co2 is emitted somewhere else to keep it running.

[@BenIsInSweden]

Less than half of the UK's electricity is generated by gas. Also even with gas power only being about 50% efficient, a COP of 3 on a heat pump still means that 1kW of gas makes about 1.5kW of heat, vs ~0.9kW when burnt at the home, so 40% less gas is used for the same amount of heat, in addition carbon capture is possible at the power plant as well to reduce the co2 there, something that isn't feasible at every home with a gas boiler. Also you can choose a green tariff in the UK, so that the cost of your energy usage goes towards 100% renewables. (doesn't mean the energy entering your home is green, just that your usage depending on specific tariff either fully or in part goes to supplying the grid with that amount of renewable energy).

[@CX23882]

I'm guessing 3.2

[@UrbanPlumbers]

Very close

[@SouthIslandSk8]

19 degrees is too cold for me

[@SouthIslandSk8]

He'll be ok when he installs UFH! but he won't be ok when he sees his electricity bill. Feel sorry for these poor sods who don't know any better.

[@SouthIslandSk8]

Co2 is the GAS of life. It makes the planet greener. Professional growers use Co2 around plants to make them bigger and healthier. The idea that Co2 emissions are causing a disaster is ridiculous.

[@SouthIslandSk8]

He thinks heat pumps are the long term solution. Where is all this electricity coming from??? Because renewables aren't going to provide it............. Are some poor 3rd world countries going to be burning coal to supply the energy to this guys heat pump and electric car?

[@Swwils]

Why is this guy not on a tariff where the export price is higher than divert saving?

[@UrbanPlumbers]

How can it be? You almost never get more on export than you have to pay for import?

[@Swwils]

@@UrbanPlumbers that's not true. The latest agile tarif called flux has a 35.12p export rate and a 19.8p import rate. I haven't used my eddi since I bought it and it's stupid pricetag means it would take ages to payback anyway.

[@UrbanPlumbers]

@@Swwils It may be at the moment, but those things change so quickly that solar diverter still makes sense.

[@Swwils]

@@UrbanPlumbers it doesn't since even the SEG export rate is 15p per KWh. So whatever tarrif this dude is on should be cheaper than that on its off peak rate, when he's charging his HW cylinder.

[@lukaszk1118]

​@Swwils I think you got them rates wrong way around

[@redshift3]

Guess 2.8 COP

[@6brman224]

I've been retired from this trade for 4 years. My experience with heat pumps was not favourable. However, don't take my word for that. But neither should you take the word of someone flogging the stuff. Go and talk to customers who have had installations done, see what they think. I worked for a commercial company, we occasionally installed heat pump systems designed by consulting engineers. Most end users were dissatisfied. But what do I know? 48 years in mechanical services, doesn't prove anything.

[@UrbanPlumbers]

Install them badly and most of your customers will be disappointed. The fact that you do something for a long time does let always mean you do it well. ‘We have always done it this way’ phrase comes to mind.

[@BenIsInSweden]

"Go and talk to customers who have had installations done, see what they think" So... exactly what Szymon has done in this video and his previous one? 😂

[@UrbanPlumbers]

You can’t make some people happy or open their eyes no matter what you do.

[@juniorplumber1275]

You are the best

[@mihaiachim5299]

@ 8:00 it is not fair to say that a heat pump costs only 6000£ ( the difference in money does not appear from the "green fairy" ) because someone has to pay the difference up to 13000£ - that money for someone to have a "greener" house is paid by the rest of the taxpayers.... what seems immoral/wrong to me... 25,000 E were spent on this relatively small house - with this money it was possible to bring the thermosystem of the house to the @ level of a passive house ... - less energy consumed in summer on air conditioning and much less energy consumed in winter on heating ... if out of £13,000 only the gas boiler had been replaced, it would have cost £2-3,000 and if the rest of the money was used on the thermosystem (ideally at the time of execution of the thermosystem, not as a retrofit) for the same amount of money invest the solution with a gas boiler it would have been more efficient than the heat pump + the reliability and maintenance cost would be lower than the heat pump... Not all houses have an unused attic on the house - some have a flat roof and this means that if you install a heat pump with all the accessories you lose a relatively considerable space in the house... - if you put the built value of that lost space + the value of the land used it will you have an even worse investment in the heat pump.... + heat pumps have much more expensive repairs and maintenance than a gas boiler... - we have many heat pumps from Mitsubishi (a brand with a good reputation over time - but with quite a few problems in recent years) with defective compressors ... you are playing Russian roulette with heat pumps - you don't know if yours will have extremely expensive problems or not and which will make the investment much more unprofitable in the medium and long term and all this to say that you are "greener" ….

[@BenIsInSweden]

But are you okay with the "do nothing" approach that means the government will use £182 billion of taxpayer's money to upgrade the gas network to fully support hydrogen? Because for the gas industry, they don't care, the customer will end up paying the COP26/Paris agreement levies anyway. Here in Sweden, it works better (not really for heat pumps as they are already very much established here), the government grant for green energy - mainly solar installs (20% of the total cost, up to 50,000SEK ~£4K in any given year), but only if you've paid more than that in tax that year; if you've paid less then you make up the difference. Technically, this would be similar in the UK, as I would expect anyone in the UK going for the BUS scheme, would be employed and paying income tax regardless. As for reliability, many are guaranteed for at least 5 years (the arotherm+ for 7 if installed by a partner). Also, many UK home insurances cover at least in part a failure in the heating system, so if your compressor is defective after the guarantee period at least the lion's share of that should be covered by insurance.

[@PatTowey]

It always seems a strange point to say that using public money to improve things like not polluting is immoral especially considering that I am a taxpayer rather than some completely external beneficiary. We tax people who pollute through policies like Vehicle Excise Duty so why is the inverse controversial?

[@mihaiachim5299]

@@PatTowey I agree to pay for "green" investments from taxes, but public projects, not individual private projects... + this system only helps those who already have enough money, not those who don't have £15-20k free around the house... and money is collected from everyone but the beneficiaries are only those who have money... so my opinion is that this type of "projects" are immoral and discriminatory... I would be ok for this money to be used on public projects - the construction of industrial photovoltaic parks ... or the installation of heat pumps in schools and public institutions, charging stations for electric cars .... otherwise dust in the eyes ;)

[@Purebeltersteve]

So hes spending the same, thing is what gas boiler did he have, obviously if it was a combi boiler, people are not understanding, the hot water demand is the reason why gas bills are so high. If he had an unvented in situ already, i can guarantee he would be paying less for money having an SE combi boiler than a heatpump. If it was condensing, it woukd be 30 percent cheaper again than the SE. How can people not see this. I cant wait to see these interviews in 5 years time. Pure FAD. Ive seen them ripped out and NI is far colder than England

[@UrbanPlumbers]

He had a system boiler with a small cylinder

[@UrbanPlumbers]

And most condensing boilers run at exactly the same efficiency as SE boilers anway

[@mcDarkD]

i like honest opinions, occasionally? what does that mean, lets take a corretly installed systen against an incorrect one? i know you do jobs right. do others?

[@ockeridge]

COP 2.93

[@danpye1991]

Cop 3.2

[@UrbanPlumbers]

Everyone seems to be getting cop 👮‍♀️ spot on today 🤣

[@danpye1991]

@@UrbanPlumbers Awesome! What flow temperature was this running at?

[@UrbanPlumbers]

@@danpye1991 it is run with room influence so hard to say exactly, as it will ignore the heat curve if the room does not reach the temperature. I think it is limited to 55C at the moment.

[@simonloker8334]

3.8

[@ecybernard-com]

Where are the smart thermostat graphs like ecobee produces showing the actual run time, and room temperatures? Talking about it is meaningless without real proof.

[@UrbanPlumbers]

Real life experience with heat pumps is meaningless? Ok 😂

[@ecybernard-com]

@Urban Plumbers its vague he claims is whole house maintained temperature. I want hard scientific data collected from each room in the house at least hourly for at least a month if not more

[@mihaiachim5299]

@ 8:23 - Vitodens 111 - not more than 2000£ + i will give you @ 1000£ for the installation of the boiler - Vitodens 111 is equivalent with a Gas boiler with a hot water tank of @ 180 liters… + much less space + + maybe lower energy losses through boiler insulation in the boiler + internal pipes. However, I consider you an extremely skilled plumber - well above average, only that I won't give you as much credit for economic decisions when it comes to investments... :p ;)

[@aerenewables]

cop 2.7

[@TonyLeach-airguntech]

Funny how Bosch is saying our housing stock generally is unsuitable.

[@UrbanPlumbers]

They have no clue really

[@TonyLeach-airguntech]

@@UrbanPlumbers don't agree sorry

[@UrbanPlumbers]

Don’t agree with facts? I have installed heat pumps in Victorian houses with no insulation without any problems and they run cheaper than gas boilers. As I said, WB are clueless about heat pumps

[@singlendhot8628]

Wait....so he basically was paying the same amount as he was with a non condensing boiler? How is that a good development? Yes, his SCOP will go up with double radiators and UFH but not by 2X!

[@UrbanPlumbers]

It will go up by around 1 so it will be 20-30% cheaper to run than a gas boiler and he can also use solar pv to run a heat pump

[@singlendhot8628]

@@UrbanPlumbers With the greatest of respect, Solar PV won't generate enough to run the circulation pumps, let alone a heat pump, during the winter. They'll need a minimum of 10 kW of battery storage to buy cheap night tariff electricity. I think the decision to go with a AroTherm+ was the right one but compared to a Viessmann 200-W boiler, they'll be lucky to save more than 10-15%, if anything at all. Would be great if you could do an update video on the V200 installations you have done as well!

[@UrbanPlumbers]

He uses 15kWh a day on average in the winter and on some days solar PV gets him 40% of that. Granted not in Dec to Feb, but in March solar PV starts to cover quite a bit of energy use. Solar PV + HP will beat even v200. You can only push gas so far.

[@singlendhot8628]

@@UrbanPlumbers On our installations, they are so close to each other, even with PV, from Dec - Feb. Maybe 10% in favour of the heat pumps if that. Let us know if you're seeing something different? Shoulder months are when heat pumps do much better thanks to PV, to your point.

[@PatTowey]

@@singlendhot8628 Even in Feb, we got on average 40% of our total consumption from the PV - March is over 50%.

[@peternorman2563]

Well living in a mid terraced house makes a huge difference ! If you had a detached house with four exposed external walls then this would be a non starter !

[@jibbily]

COP of pi 😂

[@UrbanPlumbers]

Pretty much 😂😂😂