PAY LESS FOR HEATING!! | The Secret To Boiler Efficiency | Consumer Advice

[@HeatGeek]

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[@rayakins]

This is brilliant advice. According to my smart meter I have saved about 60% of my gas bill by reducing from 70 to 55 on the hot water and 60 to 45 on my combi. The house is marginally warmer as the heating stays on for longer rather than cycling. For people living in rented accommodation who can't change their system this is massive. Thanks!

[@HeatGeek]

Please share it where possible! And tag us

[@gijsqwerasdf]

60%? Holy cow, what were the old settings?

[@leemorgan8725]

How much has your electric bill gone up, as it’s taking longer to pump the water around the house to reach the set temperature.

[@lynchetts]

@@leemorgan8725 Correct - because the pump is working for longer the electricity bill will be higher and that will offset any saving in gas. A combi boiler uses about 200W of electric and electric is far more expensive than gas so its not all good news.

[@leeknivek]

​@@lynchetts a water pump that size is only using something like 10w

[@1240Connor]

I've always wondered about the temperature settings on our combi boiler. They must be there for a reason and I've thought there must be temperatures that are more efficient than others, but without this information I've never wanted to make any changes as you assume it's been set that way for a reason. Thanks for putting this together and I'll be giving it a go with lower temps to hopefully make it more efficient and save money!

[@philipbroggio9315]

Did this last winter. Previously used 15650 kWh of gas for heating and hw cylinder. Stopped using gas for hot water (I now have solar plus Eddi and Octopus Go ) . This reduces gas to 12000 kWh for heating but my flow temp was set to maximum by British Gas who serviced the boiler. I flowed between 40-50 degrees and had thermostat set to 20 early morning and evenings with set back of 19 during day and 16 at night. The result was we used 7000 kWh a reduction of 42% . We have subsequently had a heat pump installed !

[@alistairbyron4455]

Nice video, i understand it is focused on saving energy, however… if you run your hot water at a higher temperature and then are having to cool it down with cold, it is beneficial because you can achieve a much higher flow rate and if you are someone that loves a good shower you may prioritise that higher than saving money on water usage and energy bills. So not completely pointless in all regards, more from a financial perspective. Thanks, love the vids, very informative!

[@TheJamesM]

When I had to have my combi boiler replaced the guy who came to install it warned me that the hot water temperature would be very high, but that it had to be like that for some reason. I did wonder why there was even a setting for it if that was the case, but it was working OK so I decided it wouldn't be worth the hassle of fiddling with and in my mind potentially messing it up somehow. With how energy prices are going, though, I'm definitely going to give that a go. I am a bit put out that he'd just tell me that that's just how it should be. Even if it wasn't worth his while tuning it himself, he could at least have told me that it's something I might want to adjust myself, rather than essentially warning against that.

[@johncantor4056]

Excellent! Simple and concise. The most valuable 10 minutes for anyone with a boiler

[@smgroves26]

A lot of TMV's require between 8°c and 10°c higher than the required temperature from the outlet I always advise my customers to keep hw temps around 48 to 50 Deg max on my combi boiler not heat only boiler. to satisfy these mixer valve stats. Been running by vaillant ecotec 831 R1 on 50°C flow temp for 14 years this year. The cost of keeping my house around 19°c 12 hrs/day and 17°c at night 12hrs is around 60%lower than all my neighbours same house similar setup. I also haven't changed any flow/heat related components in my boiler as the thermal stress, stop start wear has been massively reduced in comparison to boilers same age in my customers houses.👊

[@HeatGeek]

Yes we make the tmv point in the video

[@panamericanmodels]

I don't know how people are achieving this. Having had mine at 70 and reducing to 55 made no difference to consumption. At the end of day its the dials on that gas meter on the wall that count and I found they still ticked up about the same regardless of flow temp. And I did similar comparisons as best I could with time/temp.

[@hazmat5749]

My very basic 35 year old boiler has a flow temperature of 53 degrees, but it's quite capable of heating the house even when it's below freezing outside. Just one moving part (the gas valve) and hasn't been serviced for decades. I will be changing to a heat pump soon but nonetheless will be sorry to see the old Elan2 go.

[@abbabubba3452]

Just recently got a new combi boiler installed. Contrary to the advice given here, the gas engineer told me to keep the dial for radiators at max.! I'll definitely follow the Heat Geek advice. I already have the water temp. set at 45 C. I tried 40 C but the shower mixer didn't work properly.

[@russellthomas9391]

It will be similar to driving your car in first gear everywhere and will eventually wear out by putting lots of stress in on your boiler

[@robynrox]

People NEED to see this especially now that they've withdrawn the Winter fuel allowance for many people. My house uses a condensing combi. It's A-rated and should be using 10500 kWh for heating and hot water. It's actually using 6455 kWh average over the last two years. It's been wired up to a nest controller using opentherm for that time. But I've learnt from that that I could have basically whacked the heating and water temperature dials down to minimums (not the "efficiency" position but the actual minimum), made the heating come on schedule maybe 2.5 hours before the time I get up, and I think it would have worked well with my old thermostat and basic scheduler. I'm not sure how much I was using before, but if I was using the estimated 10500 kWh (that's the specific figure for my property rounded to the nearest 100), that would have cost an extra £258 per year at current gas rates. Thanks!

[@marinusk67]

range rating your power output means also lowering your pump speed. lower pump speed gives you also a lower return temperature and gives the water more time to give off heat

[@marinusk67]

Lowering your flow temperature is stupid because youre room isn't warm but you're boiler goes out and on and out and on so you're actually wrecking you're boiler. Need to lower your power output

[@StrixTechnica]

Weather compensation aside, does what you say about flow temperature also apply if your thermostats support OpenTherm? I ask because I just installed a Tado system of smart TRVs and wireless receiver (EU version, so has OpenTherm, as does my Intergas combi) and figure that therefore I could turn the max flow temp _up,_ knowing that the receiver will dial back flow temp as demand decreases. -Was that a daft thing to do?- (Yes, it was.) ETA: Ofc it might not be safe to assume Tado's OT set points are sensible. I guess I ought to monitor the CH return temp and knock back the max flow temp if it's > 40-50°. ETA2: So I gather Tado OT defaults to a maximum of 80° anyway and what I set on the boiler itself doesn't matter. And also, the Tado for Installers app lets you configure the max flow temp. Thanks,

[@davidfarquhar3917]

Excellent video and well explained. I presume turning down the flow temperature will cool the radiators slightly, which may affect how well they dry clothes on an airer next to them. Will be interesting to see how much difference I get going from 70 down to 60 degrees

[@boddamnit2504]

I had a new combi gas boiler installed a couple of years ago and just assumed the fitter had set it up efficiently. After following the instructions on this video my first months results are unbelievable. Gas use down to under £28 for a month. Don’t remember it ever being so low.

[@HeatGeek]

Thats awesome thanks for letting us know!!

[@boddamnit2504]

@@HeatGeek The craziest part is I was able to turn my combi hot water down by 20 degrees with no impact on my lifestyle whatsoever.

[@aliasgharkhoyee9501]

@@boddamnit2504 Imagine when gas prices go back to normal. Energy costs could be dramatically reduced for people who learn about lower flow temperatures.

[@Kez1a1]

@@aliasgharkhoyee9501 jezzzz some people....do you think they will ever put gas prices back to "normal"???

[@aliasgharkhoyee9501]

@@Kez1a1 Who is 'they'? Is there a conspiracy keeping gas prices high? :) Unfortunately we live in a world where basic survival necessities are controlled by temperamental market traders, who are easily spooked by world events (or they're expecting everyone else to be spooked, and trying to get ahead of the expected price rises by increasing prices themselves a little bit). You and I can become one of these traders and then we'd be the ones 'controlling' the prices. There needs to be a radical shift in the way basic goods (needed for people's lives) are exchanged. Their prices cannot be determined by the mere clicks of traders - as if it's a trivial game. Perhaps only those people/companies who can actually take the inventory (who have proven storage facilities) should be able to bid on oil and gas etc, rather than any random trader without that physical storage capacity.

[@You-Tuber2024]

I’ve tried running my Baxi 400 conventional boiler at 60 degrees and it just doesn’t warm the house up at all. It’s set to 75 but this seems too high according to your info??

[@MarkBallardLTD]

Good advice. I've been telling my customers to do this for year's.

[@sevastoskoumtzis5401]

Limiting the boiler max output "range" will not really change much! That is, because the boiler will only run at this power level during startup, then it will regulate to much the set temp. Therefore, the only minimal gain is during the first minute or two, that the return water is too cold for the boiler to achieve the set outlet temp. If we also consider the increased boiler efficiency because of the colder return water, the benefit ends up very small, being a function of thermostat cycles, that should be reduced anyway. Also in a very cold weather snap or a home reheat after days, a need for high flow temps may arise. In that case the limited boiler output could hinder its ability to deal with such conditions. This is especially true with under floor heatting. As a result, the recommended control paramiter is flow temperature, that can be adjusted relatively easy by the occupants if necessary. Obviously this only applies to combine boilers that already have a big output to accommodate DHW use, it is not a recommendation for sizing the heating appliances.

[@easytigeruk15]

Just a quick one to say keep doing what you are doing chaps. Absolutely fantastic channel and the advice is second to none. Keep up the great work and I hope you keep managing to grow the channel and the business, doing so gives me confidence the industry is heading in the right direction! If anyone asks me anything plumbing related I send them to you and a shoutout to @Urban Plumbers. You guys really are doing the lords works :)

[@thornhillplumbing]

Turn the radiator knob down as far as you can without the house feeling cold, and turn up the hot tap knob all the way to max if you want a fast filling bath or a banging shower 👍

[@jericho_bees]

@@thornhillplumbing I think that you are missing the point. The TRV only throttles the water coming through to maintain a constant temperature. It doesn't make it more efficient. You want an efficient temperature when it reaches the TRV in the first place and a balanced radiator so that it doesn't need to be throttled back.

[@kevinhill1851]

We’ve been trying to get to the point where we have a full ASHP quotation for our house since November last year. Our chosen supplier, who is not only MCS registered, but also an installation validator for the MCS, seems to be doing everything possible to persuade us out of getting a heat pump. There is no doubt that our property is awkward, as the heat pump will have to go up the garden and there will be lots of trenching under existing paved patio and steps, but he also expects that all the emitters are going to be too ineffective. Yet we have run our gas boiler over the whole winter with a flow temperature of 50 degrees and managed to heat the house perfectly adequately. I guess he is either looking for a much lower and thus more efficient flow temperature, or just is guessing wrong ahead of the full design - a design that he seems very reluctant to perform. Odd situation really.

[@HeatGeek]

It's not that odd. The calcs HAVE to err on the side of caution so I guess that's why

[@thornhillplumbing]

The installer probably thinks your house and existing system isn't suitable for a heat pump for what ever reason , and is giving you his opinion that going ahead with the job may cost you far more than it will save. Also if any problems or the house doesn't heat up properly or if it ends up eating lots of electricity, it will be a headache for him down the line.

[@MrKarlPrince]

A significant additional improvement for hot water temperature and efficiency is to insulate the hot water pipes as much as possible. The temperature drop between the boiler (or tank) and the tap can be considerable, also it reduces the length of time for hot water to come through on intermittent use.

[@ASingh1699k]

Excellent and timely advise. Thank you much appreciated. *Visuals showing the changes/dials you are referring to would benefit those that are less familiar with heating systems.

[@recyclist6421]

I hardly use any hot water. I generally use the local swimming pool and gym to wash. I also don’t use much heating as house is well insulated and big south facing windows in lounge. I have a normal system boiler with a hot water tank. Can I just adjust the boiler temp to 60-70 oC when I put the hot water on (usually about 25 min per day) and then reduce it right down to 45-55oC when I put the central heating on. The heating is obvs on for a lot longer per day than the hot water during a Scottish winter

[@rhyannone]

Thank you so much for this, so good of you to explain how to save, in this crisis. Well done.

[@KiLLaBushWooKiE]

Interesting, is slightly confusing espec when we have a combi boiler but no smart home device to know of power output cost etc. So let's say we have our heating temp at 50 at boiler, is it best to set temp at house thermostat at say 20 and keep heating on all time so it stays around that or manually turning it off and on when required. Which would be more cost efficient. For example we have a hot water kettle that keeps it hot at low power and it states its more efficient than if you kept reheating it as a standard kettle.? Thanks

[@enzadurban7967]

I have been told by a previous engineer to keep hot water temp at above 60degrees to prevent possibility of legionnaires disease? Is this only true of systems using a hot water tank? Thanks!

[@HeatGeek]

Above 60c is scalding. Very dangerous. Above 50c prevents legionairs. Legionaors fies in 2 hours at 50c

[@jerryhilditch5991]

Thanks for the video, I've adjusted my boiler settings on your recommendations and look forward to the savings.

[@dmc6617]

I reduced the flow temp in a combi boiler from 55°C to 40 and it consumed more gas, struggling to raise the temperature. Not sure that the advice to lower flow temps to minimum possible works. I think there is a sweetspot of maximum efficiency.

[@avivscrewvalla]

Really liking the efficiency theme! I'm getting a Heat Geek (Simon) installation this week and we struggled to lock down on the most efficient boiler option available. Would be incredibly helpful if you could do a HG video review of the most efficient system / heat only /combi boiler options for consumers if a heat pump isn't viable/ available. Love the channel and the hard work you're doing to save us all.

[@HeatGeek]

Thanks! The most efficient boiler in my opinion is viessmann 200 with weather compensation for all the options due to its modulation range. So get one of those.. If heat only will need to revert to a viessmann 100

[@avivscrewvalla]

@@HeatGeek Oh thank God - we mutually agreed on the 200-W thanks to the lowest modulation ratio on any boiler we could find + being H2 ready. There is a dearth of available content on this exact subject btw..

[@HeatGeek]

@@avivscrewvalla h2 ready is a gimik, those boilers will never see h2. But yes agree

[@SprocketN]

The discussion about legionella is important, where I work we have a constant battle with legionella bacteria in our manufacturing processes. However our tanks don’t change their water fully even over a week and our processes spray water creating potentially contaminated droplets in the air. A domestic hot water tank would have its contents replaced daily in a family home. Legionella is a respiratory disease and can only infect you by breathing in the bacteria in water droplets, when having a shower. You can’t get Legionnaires disease from drinking contaminated water. If you have an electric shower and don’t use your ‘from the tank’ for showering then you probably going to be ok with lower water tank temperatures. Or as has been suggested, ‘boil your tank once a week’ like we do where I work. We raise the temperatures to above 80 degrees, in a domestic tank 60+ would be fine.

[@singlendhot8628]

Excellent video! Well timed!

[@gregmusto3336]

My Combi boiler has an e on the radiator temp dial for efficiency. I keep it at that, so what you are saying is to drop it below that level and my 2018 boiler will be more efficient?

[@HeatGeek]

Yes exactly that. E is the beggining.. the lower belownthe better

[@gregmusto3336]

@@HeatGeek going to need to remember to do this in the winter! 🥶

[@oojimmyflip]

why do engineers always turn up the flow temp on a combi every time they service the boiler?

[@OOK11]

My shower has been either scolding me or freezing since my engineer came just realised after watching this video he had changed all my settings.

[@danielardelian2]

I have a small comment about lowering the flow temperature too much. I have a small, well insulated house with 100 sq. m of underfloor heating. There is no zoning, all loops are constantly open. Heating is provided by a condensing gas boiler that has a minimum thermal power of 3 kW (1:8 modulation rate). If I set the flow to 28 degrees, the underfloor heating supplied with 28 degrees water is only able to dissipate less than what the boiler puts in at its minimum firing rate. The flow temperature quickly overshoots the target 28C and the boiler starts to cycle on-off like a sewing machine. But if I raise the flow to 35 degrees, then all of a sudden the floor can easily dissipate the 3 kW of heat and the boiler purrs like a kitten for an hour until the thermostat turns it off. I wish the boiler had a lower min. firing rate so the heating could run for longer periods of time at a lower steady power.

[@Extragonk]

Thanks for this, it’s affirmed what we’ve been trialing over winter to turn the Worcester Bosch down to a flow temp of 35-40 and that’s managing to keep the house stable at about 20. But we’ve noticed that even though the boiler has individual hot water and rad dials, the hot water remains a bit cold, so will have to have a look and see if the cylinder immersions even working or not.

[@copperskills3973]

Hi. If you have a hot water cylinder then you need to keep your boiler thermostat high otherwise like Adam said in the video bacteria will form. Another alternative is to run your immersion heater once a week to heat up the water to 60 degrees plus to kill all bacteria build up.

[@Extragonk]

@@copperskills3973 yep that’s what I was expecting the immersion heater to do, with the boiler itself still set high for hot water, I expected the difference between flow temp from the boiler to be seen at the tank as low and have the immersion do the rest of the lift. But yep we’ve been doing manual high heat cycles to keep safe

[@copperskills3973]

@@Extragonk unless the boiler is connected to the cylinder with Worcester Bosch controls using their bus communication it will not do that unfortunately and the hot water symbol on the boiler is redundant and doesn’t work

[@Extragonk]

@@copperskills3973 thanks for the info, that sounds like the case unfortunately!

[@brackcycle9056]

@@copperskills3973 Yes, It is worth remembering around 250 people catch legionella each year in uk so it pays to be careful.

[@davidragen1851]

Just throwing a question out their can you get a solar panel system that will run an electric boiler so u don't need a gas supply to your property?

[@HeatGeek]

This is essentially what a heat pump is.. but yes.. electricity boilers use 3.5 x more electricity than a heat pump so cost 3.5x more.. don't do it if you can avoid it

[@kerilloyd7504]

What a brilliant video. You’re the best. Thank you for sharing this, it’s so simple to do yet hardly ever mentioned.

[@tamasveingartner4976]

I cannot find much information about aluminium radiators? Shall I invest into them? Just about to replace all my single panel radiators as part of a refurbishment and eyeing with double panel aluminium radiators instead of the standard type22 ones. They cost at least twice as much though. Does it worth it in a 3 bedroom terraced house with 9 radiators?

[@nigelhayes40]

Can incorrect vents in your A rating house increase your bills when you have a heat pump? What vents should I upgrade to from the generic one I got with the house.

[@mryan4452]

What is the ideal flow temperature for traditional older non-condensing boilers? I see so much info out there about combis and condensing boilers, but almost nothing about the older boilers. I don't have a hot water cylinder BTW so no concern re legionnaire.. Is it better at a lower temperature like you recommend for non-condensing, or would it be inefficient or cause other problems (such as being more likely to break down or something)?

[@papageo8]

Hi there, been using steady state through Oct and Nov. Slowly increased the flow temp on the heating from 30c to 31c 2 weeks ago to 32c 2 days ago. House always holds >18c with fluctuations between 18c and 19c. Current use 50kw gas a day BUT our heating is on 24hrs a day. Great results!!! One question we are going away for 4-5 days. Are we better turning off the heating and firing back up just before we get back at high or low flow temp or leaving it on at current rate or lower the flow rate to say 25c?

[@rhonddalesley]

I’m not sure if I’m understanding you correctly but I think it sounds great, can you explain in a way that a muppet could understand please because I’d like to try it 😁

[@mallamal5578]

Won't having the heating and water on for longer - low and slow cost more in electricity to run the pump?

[@colintinker7778]

Brilliant information. Thank you for this. Airing cupboard... I'm heading there now!

[@christopherbarton8328]

Thank you for the excellent content. If I'd known all that I've learned from your videos in 2021 when our boiler needed replacing I'd have looked further into a heat pump. Anyway, we now have a Worcester Bosch Greenstar 15i and Hive - groan! Having finally understood weather compensation and modulation, which weather compensating smart controller would you recommend? I've asked the installer for a quote for the Worcester Bosch Sense II, but is that optimal? Thanks

[@HeatGeek]

Stick with sense 2 yes!

[@christopherbarton8328]

@@HeatGeek Many thanks!

[@marktrewin4726]

i use the wave and its weather compensation program is spot on its a two core cable back to the boiler power over network so its easy installed.

[@christopherbarton8328]

@@marktrewin4726 Thanks. Will look into it.

[@marktrewin4726]

I use the worcester wave on a 440 cdi erp and it works very well, i have a large bungalow so the gas used this year using the compensated control is over 30 lower than the same time last year when i experimented with normal fixed flow and room set point. I think the difference between the sense and the wave is that the wave gets whether updates and can use optimal start stop control in eco mode.

[@john1080]

Will somebody please talk about short cycling! My thoughts.. I have an Ideal boiler with Ideal's Halo thermostat which turns out to be very primitive. The boiler heats one radiator with an output of about 400 watts. The boiler has a claimed efficiency of about 90% at 4kW output so 4kW for me and 400W for the garden. With the Halo thermostat the boiler stays on until the room temperature rises above the cut-off point of the thermostat. The boiler can only produce 400W output by generating heat for roughly 1/10th of the time it is on. Unfortunately the boiler blows air through the hot heat exchanger regardless of whether or not there is gas being burned so the garden still gets 400W even when the boiler isn't producing any heat. In fact the load on the boiler is really 400W for the garden and 400W for the radiator so the boiler produces heat roughly 1/5th of the time its on with an overall efficiency substantially lower than 50%. I must admit I wouldn't have known there was a problem if I didn't have a Vaillant boiler at another property and can see that the Vaillant boiler and thermostat produces about the same amount of heat while using less than half the amount of gas. Is there any way to increase the efficiency of the Ideal boiler or should I scrap it?

[@micheals1992]

Running your boiler for longer, would it be possible the gains would be offset by the increased electric usage? The pump uses about 300w!

[@SprocketN]

The small increase in electricity use will be easily offset by the reduction in gas use. Overall your bills will be lower.

[@ched999uk]

Great info, thanks. I was trying to find if there is an optimum flow and return temp to get the most efficiency out of a combi boiler?

[@HeatGeek]

No. Only thr lower the better

[@shmavitz]

For condensing boilers the return temperature should be below the dew point of water, which is about 55C, for maximum efficiency.

[@MrKlawUK]

does lowering hot water on a combi reduce hot water pressure (eg for mixer shower using only mains pressure)? or will the lower flow temp allow higher pressure mitigating that? as with lower temp you’d need less cold water but I’m worried that would reduce the pressure of the shower

[@TheZippyMark]

Short answer no, long answer potentially. Lowering the temperature will do nothing to the pressure of the hot water BUT if you're now using exclusively hot water it could potentially reduce the flow as you're restricted to what the boiler can produce, but then again most shower's flow rates will likely be less than the hot water flow rate anyway, so maybe not.

[@Chequr_Prostate]

Is there any benefit in adjusting the water flow on your unvented hot water cylinder? I noticed that there is a isolator on the return pipe.

[@1240Connor]

Do you have any sources for this information as I'm interested to read more? Or if not, would you consider doing an experiment maybe with a shower at 35C and measure gas usage over 10 mins of a boiler set at say 60C and 40C. Perhaps even test a few further temperatures as I would be interested to see if there is a point where temps that are too low actually reduce boiler efficiency (I'm thinking along the lines of a car engine where it is most efficient at a middle speed of 56mph ish)

[@HeatGeek]

Lots on our website at heat geek dot com. Read the condensing theory one. The lower the better. It doesn't stop. 1c is the most efficient

[@luckystrike656]

Can I sett something else on a Vaillant condensing combi boiler other then the heating curve? Now it's sett at 0.90 but it's not good when outside its not really cold. I am trying to make the curve more flat, from 30-50C°. I'm not expecting negative 20c° outside. I have an external temperature sensor too

[@roscopeco2000]

Hello great vid as ever, your a very good. One question you said if you can run your combi at 55deg flow temp you said you will know your OK to run air source pump. What about flow rates though? I touched on this with a comment before about pipe types. Is the flow rate of air source comparable with a boiler? Ie will I not need to increase the diameter of my plastic pipes?

[@HeatGeek]

Hi there. Yes the flow temp is relevant to the rads only. Most pipe work is fine to be hinest but just incase we have a video regarding pipework here m.kzbin.info/www/bejne/fnfPepWEdrqKobs

[@garythompson4133]

I have a Grant oil boiler with unvented cylinder, some CH rads and Ufh in some rooms. Is there any way an oil boiler can be modified to have the separate hot water and heating flow temps? It bothers me that the 60 degrees flow has to be mixed with a significant amount of cold water for the Ufh.

[@davidoddy4668]

Hi , I have a system boiler and I have option for setting temps for both rad heating and hot water. . So does this mean I can set my hot water to 60degree and my heating to 55degrees or lower when testing comfortably on lowest flow rate without any concerns ? Temps between the heating/water don't need to a minimum apart from one another ? Thanks

[@snips73]

I have a question. In a large house 5 bedroom + Is it more economical to have a hot water tank like a mixergy or a combi in a large house?

[@iamtoooldtocare]

The number of bathrooms generally determines the effectiveness of a combination boiler. If you have two or more bathrooms then a standard (30kw) Combi will struggle to cope with demand as it will only deliver to one hot water outlet at a time.

[@tonybaker55]

I have a condensing combination boiler, but there is only one control on the front for the radiator temperature, that runs from cold, 1,2,3,4,5,6, max. I currently have it set at 4, but how do these numbers relate to temperature?

[@HeatGeek]

What boiler is it?

[@tonybaker55]

@@HeatGeek Worcester Bosch 24i Junior.

[@mutley23able]

Is it worth keeping the pre heat turned on or off? Makes me think that I would use more water, waiting for the water to heat, so would cancel out any saving being on a water meter.

[@HeatGeek]

It really depends how much you use it but heat is more expensive, and higher carbon than water so off imo.

[@mutley23able]

@@HeatGeek Ok thanks for that

[@mutley23able]

was thinking of trying the low and slow method as well this winter so, the boiler would stay warmer as well, so I probably wouldn't need the pre heat. House is a new build so is well insulated, will compare the KWH used and the price to last years, on and off blasts 👍

[@DanPilborough]

You might want to point out that for the uninitiated like me that you are not taking about tank thermostats which must be left at 60 Deg to kill bacteria. I initially got confused as my boiler is an ideal heat 18 and doesn't have anything to indicate the exact flow temperature. It has dial but only has Min, Max and Economy (whatever that means) marked. Any idea how I can tell the flow temperature in such a set up so I don't set a flow temp below 55 Deg?

[@HeatGeek]

Economy is usually 70c ish.. below that I can't help. The cheaper the boiler the less options and functionally unfortunately. Ideal is pretty basic in offerings

[@user-ry7yg2hk7i]

And best efficiency for hot water is when the hot water tank is hygienic boiler with no legionella at any temperature. Efficiency for hot water on combi boiler is less then 80 vs. more then 90 with hygienic boiler and the flow of water is key to economy.

[@myatix1]

This is really valuable information Thanks for sharing! It would be great to have more content for properties with 100% UFH. Reducing a boilers flow temperature to 35 degrees is probably not that great in terms of condensation efficiency I would imagine? Especially with mixer valves on manifolds etc

[@HeatGeek]

Reducing boilers flow to 35 is amazing for effy

[@daveofyorkshire301]

I've just recently - the last week or so turned my heating on permanently and set the heating to 19.5C during the day (05:30-22:00) and 17.5C at night, it's reduced my bills by 10% the first day and another 14% the second day when I turned down the radiators from 70C to 50C. I have no temperature issues, the heat isn't yoyoing and so far being on all the time has actually significantly cut the bills. When before two hours in the morning just didn't reach set temperature because it was impossible to get the 10C to 19.5C in that time frame, that first day of permanent heating it took 7 hours to reach temperature and I had to eat a large bill that day (smart metering)... Since starting the economy kick over 10 years ago, I've done cavity wall insulation, two loft installations and blocked old vents up that were needed for gas fires removed ten years ago... Being sealed in I had to get a dehumidifier to prevent condensation and steam issues when I have a bath, but all in all from the old gas back boiler to now I've cut over 70% on my original bills over ten years. I'm still looking for more, but heat pump grants are only being offered with underfloor heating and I have concrete floors, which excludes me...

[@HeatGeek]

Heat pump grants are only being offered worh underfloor heating? This is completely untrue

[@daveofyorkshire301]

@@HeatGeek which company is offering grants without under floor heating? I checked there are very few offering grants and those that do - that I'm aware of - require under floor heating to be installed as part of the package, and you can't install under floor heating when you have a concrete floor... or so I e been told. So please tell me who ? Because last I checked there was only one company still available under the grant scheme, if I'm wrong please tell me who else?

[@HeatGeek]

@Dave of Yorkshire litrally every company in the UK can and will install without underfloor heating.. I speak to many many different companies every single day and I've never heard of it as a prerequisite. We install with grant without underfloor heating. Lastly.. you can install ufh on concrete floors.. there's a couple of options actually. You have either an overlay system or a routing system like jk flooring.

[@HeatGeek]

Check out thr heat geek map that will list a few different companies you can use.

[@daveofyorkshire301]

@@HeatGeek Did you miss the word "grant" in my post? If course companies will do it - at your expense. But not as a grant installation!

[@filbertmark9164]

How can I tell whether my system has weather compensation? I have a Baxi 600 series combi boiler with a nest thermostat. When I go to alter the flow temperature below 80C nothing happens, it stays on 80C.

[@rduggan2011]

Just Had My December Bill , So will Try 35/38 and See How Much I Save, House Is Set To 18c. Radiators all at 20c, But Of Course Heating Goes Of At 18c. Was Using 2-5 Gas Meter Units Per Day, Messing With The System, Now I Am Telling Everyone, Set and Leave, What You Think Guys? Oh By The Way, I Have No Income At This Time, My Company Collapsed , Due To Last 2 Years.

[@Supplementbenefits]

So would you keep the boiler on at all times but just keep it down?

[@johncostello9388]

Hi I like the videos and advice but could you do one on a complete cost to an average house for a heat pump, this should include the pump, wiring, and plumbing, plastering, retailing and redecorating. As most houses have 10mm feeding radiators and would need to be replaced these have been sunk in walls behind plaster board, and the joint or unequal tee will be under your floor which will have to be lifted bedrooms bath rooms etc, I think people need to understand the true cost. I’m not against heat pumps but when you see headlines that they are cheaper and coming down and grants offered but only for the pump not the whole job, hope you can help.

[@HeatGeek]

The answer is 15k on average. The average house doesn't have 10mm at all. It's has old oversized 15mm and 22mm pipework and definitely does not need plastering. Low quality new builds have 10mm but are less likely to need a repipe due to lower loads although those that don't want to do calculations say it might. We've done a while consumer series around this. Please start with the "do I need to upgrade my pipe work for a heat pump" video.

[@alexkalogroulis8833]

Always wondered where the 50 degrees minimum temperature (re legionella) for hot water should be measured. At furthest tap? At hot water cylinder? Advice would be welcome.

[@HeatGeek]

In commercial yes at furthest tap. There is no regs or anything in domestic

[@mikehopkins4040]

If I turned the boiler off at night time is that safe and would it lower my consumption?

[@HeatGeek]

It depends on a few variables. Watch our video on 'Should I continually heating home'

[@firestormyuk]

Hi there, great video thanks! We currently have an ideal logic 15 (15kw system boiler, I know from other comments, its basic so its probably not able to have a dual control fitted) with a Tribune XE 210 litre unvented cylinder. Will 60c setting be high enough for the tank? The plumber claimed the "eco" setting (which isn't really eco at all as its about 69-70c according to the digital display) was best because it ensured legionella would be killed as there could be a drop on the heat the boiler is putting out vs the tank temperature. The tank is only around 5 metres from the boiler! So is 60c ok? Thanks.

[@russellthomas9391]

60 is fine - will kill legionella at that temp and should use less energy to heat . As mentioned in the video try turning the thermostat on the cylinder down to 50-55 degrees because the water at the top of the cylinder is much hotter than near the bottom third ( where the thermostat is )

[@maltesetony9030]

Is there no chance AT ALL of Legionella developinh with a combi boiler? 38 degrees seems remarkably low for heating water.

[@mallamal5578]

My hw cylinder only has a cylinder stat - I assume this talks to the boiler direct?

[@shaunwalsh6354]

I’m having a new Viessmann Vitodens 100-W 35kw boiler fitted, with a Nest Gen 3 controller, should I be asking them to fit a weather compensation sensor also?

[@HeatGeek]

If it's going to be installed with opentherm it's ok

[@deanchapple1]

Hi, great vid as ever! Any tips for making oil boilers more efficient? Because they can’t range rate??

[@HeatGeek]

Buffers to elongate run times. And a controller that you can slow cycle rate

[@deanchapple1]

@@HeatGeek what controller would you recommend?

[@HeatGeek]

@@deanchapple1 evohome

[@MrThompo1]

Is there any condensing when using hot water only?

[@HeatGeek]

Yes. Although this is a whole subject

[@mickbmx]

The trouble with lowering a boiler temp with a normal pump is you might use less gas but you'll use more electric at about 80w as the boiler will be on for longer heating a home, on more modern boilers people turning down the boiler thermostat would work to save money as they have UPS3 pumps and most of the lads are fitting load comp stats..

[@HeatGeek]

About 40w more like.. nothing really

[@kevinleesmith]

I have developed a smart hot water cylinder thermostat. A) it means u know EXACTLY how hot the water is, B) you can EASILY and REMOTELY change the thermostat setting. C) see how long it takes to heat the water to the desired temperature. Woukd u be interested in it?

[@HeatGeek]

Sure.. is it commercially available?

[@kevinleesmith]

@@HeatGeek it's a new product I have developed and current manufactured by me on a ad-hoc basis. If it takes of it can be packaged as a retail product. What kind of retail price would you think people would pay? What would u pay to put one in your house?

[@kevinleesmith]

@@HeatGeek maybe we could work together on it as the first heat geek product!? Anything is possible.

[@HeatGeek]

@@kevinleesmith I have some ideas. Also have a video on this due out

[@HeatGeek]

Feel free to contact [e-mail]

[@jasonhoyes9046]

Dear heat geeks I am looking to to fit a water tank to my combi boiler using a intasol solar combi valve to maximise my PV usage with a myenergy eddi to get free hot water. my question is would it make sense as the tank is a twin coil tank could I use diverter valves on the radiator side when the tank gets hot could I bypass the boiler and pump water through the the water tank coils to heat the radiators bearing in mind I was only going to heat the water tank with excess solar nothing else. Is this doable or just a waste of time any advice would be grateful thank you Jason

[@HeatGeek]

Too little energy wouldn't be worth the exercise I don't think. Especially as pv doesn't generate much in the shoulder months or winter compared to the likes of solar thermal

[@jasonhoyes9046]

@@HeatGeek thanks 😊

[@noelburke6224]

All showers are thermostatic controlled and all cylinders should have a thermostatic blending valve,

[@91burgessl]

This is a fantastic video! Can a weather compensation unit be added to a ideal boiler with a hive thermostat?

[@HeatGeek]

Depends which ideal boiler. You'll have to put the hive thermostat in the bin though. It's the worst stat.

[@91burgessl]

@@HeatGeek it's a ideal logic +, does the hive have to go? I know they are rubbish but do not want the outlay of a new thermostat.

[@shonabailiff2778]

Mines pretty bad, iv looked at all of these tips and iv tried to alter mine to be more efficient, our bills £250 per month, the heating is only on for 3 hours per day, our hot water heats when I turn it on and it's only at 11% efficiency, somethings definitely wrong its costing more to run my combi boiler that the old dinosaur of a cylinder tank

[@bill-2018]

Interesting. I have a condensing boiler. It cleared up my thoughts about legionella. Is there a minimum temperature at which it dies? I recently installed a bath and set the boiler at 40°C and just a few inches of water is good because I don't want to swim in it. Or drown in it. A lukewarm bath in that hot weather was nice by turning the boiler down. I read the red figures on my meter to see how little gas I have used. I have just the one tap on my bath because why boil water to only cool it down. A nice old brass tap which says 'cold' on it but never mind. No idea where it came from. Washing pots, clothes and bathing i have used 0.934 units of gas so far this month to 11 th September.

[@iainmporter]

Can weather compensation and load compensation (ie Nest over opentherm) be used together or do they end up fighting each other? Our boiler has both options.

[@HeatGeek]

They can be used together sometimes. It depends on the boiler and conteol though

[@iainmporter]

@@HeatGeek Thanks. It is just a basic Logic Heat system boiler but it does have wiring ports for opentherm and weather compensation. The installers wouldn't fit the available weather compensation module saying that was only required if the boiler was going into an unheated space like a garage!

[@HeatGeek]

@@iainmporter so sad to hear

[@ram64man]

What the heat geek isn’t telling you folks is as part of April 2022 revision 18 all boiler swaps must now do a heat calculation also one of the amendments is the systems now have to conform to a max 55c for heating and hot water. Funny that they are the same levels as heat pump products. Forcing people to go heat pumps in the future I think - not on my watch , hydrogen first you can’t run industrys on a heat pump to cook your crisp , melt your aluminium for cans etc

[@HeatGeek]

First if all that's untrue. Its becoming a British standard not a regulation. There is no 'must'. And a heat loss and lower temp has always been a better standard it's not knew. If you think a hudrogen grid is going to be around jn the next 100 years then you aren't involved in the heating industry but an enthusiast at best

[@ram64man]

@@HeatGeek no it’s a requirement further to this Wooster and baxi have been issued updated information it clearly states that the new systems must be set to 55c on installation or it will affect your customers warranty , you should have got them in the mail. In regards to hydrogen for industry Not domestic) is a must with blends up to 40% without major upgrades for industry. yes April 2022 revision 18 it’s British standards but if you don’t think that that apply remember that the next time you go for gas safe registered which is also changing from 6 months experience in industry to 12 months. And reassessment every 3 years a requirement to work on for both lpg , fire places , oven’s and gas refrigerant based air source heat pump typically found with ht pumps , further to this heat calculations are being mandatory part of gnvq lev 3 /4 training , To improve and working practice in the industry . biogas is j not a. Viable option that cannot be expanded let alone the millions in cost per plant , yes you can add it to the existing grid but is 4/5 times more expensive than other methods and government own statics show it will only contribute just 8-10% to the grid at best , further to this the U.K. is currently in the middle of updating all gas pipe lines to homes replacing the old 50-60’s pipe work , is it really that hard to just make it hydrogen mix ready going forward otherwise it’s a complete waste of money. you cannot run heavy industry on heat pump technology period , if you could Germany (the eu leader in heat pump installs) wouldn’t still be dependent of fossil imports non of the alternative energy methods haven’t even thought about how to moving industrial production,it’s very nature on function it it has to burn to heat up or cook , electric is not an option to these businesses

[@HeatGeek]

@@ram64man hear loss has always been a requirement in nvq l3. I didn't say heat pumps could power heavy industry. Wait for our hydrigen video due in 2 weeks before assuming our opinion. Also.. we are the uks number 1 hydrogen fuel cell boiler installers so have a rounded and unbiased view

[@leostenbuck9946]

If we get a sun amp thermal storage for hot water is this needed. I have a normal boiler with a hot water tank.

[@HeatGeek]

Yes

[@gino2465]

I think heat pumps are fantastic idea for myself I want both working together so that in the winter the gas can supplement the heat pump or just run the heating for lower outside tempreturees. But for myself a could have free hot water all through the summer as I do with free charging of our EVs . We just need to make sure our home is heated without issues below 5degress. So really running both would be our awnser.

[@HeatGeek]

Why couldn't a heat pump heat below 5c? Have you been listening to those with no heat pump experience? I wish they'd stay out lol

[@gino2465]

@@HeatGeek lol you sell heat pumps . But regardless I would not want all my eggs in one basket. My generator would happily run a gas boiler but I would struggle with the load of a heat pump.and yes we do get more than average share of cuts. And yes we cook with electric so upgrading my generator would not be cost effective. Our home uses a generator which can charge an ev and run home any more electrical loads would require £7k extra so being able to plan for electricity cuts is vital living in rural areas. So gas or oil is or still can be used to heat or provide hot water in cuts. For this reason as I strongly believe that our net work in the UK would and could not deal with every home running on electric, proof again was this week s announcement of the ev regulation comming into force 30th June . It's very CV lear that the UK cannot presently deal with every home switching loads on at the same time. So again not all my eggs in one basket.

[@HeatGeek]

@@gino2465 if we sold heat pumps that didn't work below 5c we would be out of business and our yiutube channel would be flooded woth unhappy customers. Can you point them out? Also.. we are the uks number 1 hudrigen fuel cell boiler installers so hardly bias

[@HeatGeek]

The national grid disagree with network capacity. Watch fully charged interview woth them about this very issue

[@gino2465]

@@HeatGeek I know what you do,I have researched you and your company and seen all your KZbin videos, and I will say you are fair. But and again I want a heat pump but I am aware they are not 100% below certain temps nothing wrong with this sir. That's why I would not uninstall a gas boiler. Nothing wrong with this is a back up and to help a heat pump in colder weathers. I would have one tomorrow I like something that has an out put that cost nothing. But the cost of install is far out of the reach of the average person. I dream of having free energy between apron and October every year. What not to like sir.

[@PhillipWalker-o3t]

I understand the idea of changing flow temperature but why is the flow rate never referred to? Can you not achieve a similar affect by reducing the temperature of the boiler and the flow rate so that the boiler temperature/gas consumption rate can be reduced but if the water is travelling through the boiler more slowly will it not increase the potential for heat transfer within the heat exchanger? In an older boiler could that not be a way of increasing its efficiency? I have a very old balanced flue system and the central heating pump died some years ago. I bought a new one which a plumber fitted along with a replacement hot water tank but whilst I think the pump had a larger capacity than the original, no real time was spent adjusting the flow rate it was just installed set on a speed and then its been left running at that speed ever since. My boiler has a heat setting from 1 to 5 Warm to Very Hot. The hotter the setting the hotter the whole boiler gets. Seems obvious to me to set the temperature down as low as I can as it reduced heat transfer loss from the boiler itself into the surrounding area and as its in a utility room its largely just wasted heat.

[@HeatGeek]

Flow rate auto changes as the pump is ‘burner linked

[@PhillipWalker-o3t]

Even in a boiler that's nearly 40 years old (Glow-worm Fuelsaver 55F)? @@HeatGeek

[@HeatGeek]

@@PhillipWalker-o3t that’s non condensing so matters less. Once you go Erp pump with trvs the savings are maxed pretty much

[@PhillipWalker-o3t]

Thanks, I have TRVs fitted already. but what's an Erp pump? I have a Grundfoss UPS 15 60 130 set on speed 2 (mid flow rate)@@HeatGeek

[@Swwils]

Condensing boilers may well be mandatory but designing the system to actually run at a low enough temperature to condense is not.

[@copperskills3973]

It is after June mate

[@Swwils]

@@copperskills3973 couldn't come soon enough, Wales and Scotland have had it years.

[@MichaelPickles]

Could you do a video or just some thoughts on thermodynamic panels linked to a heat pump and buffer tank?

[@patrickwheeler2646]

Unlikely to be positive but could help people avoid the potential poor choice.

[@martinwright7093]

Yes, excellent information. On a separate issue, why the trend for repeatedly changing the camera angle. I know its very commonly done these days but its so annoying and completely unnecesary, just keep the straight on view. Grhh...

[@patrickwheeler2646]

It's commonly used in most types of recording, two angles allows for editing out any blips etc.

[@pipelineplumbingserviceslt4408]

Great vid 👍

[@liamknowles6658]

Nice video!

[@bimiuk4051]

This is so confusing! Another video f HGeek talks about going down to 45-50 degree even on a system boiler … (provided 60 degree is done to kill bacteria every so often). Whilst now you not to go below 55c So if setting system boiler to 50 and water tank stat to 50c. Is that doable and works fine? Will that be enough as well as work in condensing mode?

[@HeatGeek]

We say to not go below 55 if you don't have hot water priority.. 40-45 for hot water priority. Yes it is confusing which is why we always advise using your local heat geek.

[@bimiuk4051]

@@HeatGeek much appreciated 👍 that means even with 55c the system boiler won't be condensing. Correct? What about going down 53c on cylinder stat and system boiler 54c. Will this make any difference in efficient and save money;? (Condense too?)

[@HeatGeek]

@@bimiuk4051 yes it will condense anything below 70

[@bimiuk4051]

@@HeatGeek this is mind blowing. I loosing the plot here. After numerous videos and research it was noted that a boiler weather system or combi - will condense below 54c is this not correct? Surely condensing at 70c must be much less effecient. The key point in my case is to establish if I can get my system boiler and water tank (no PDHW) to lowest point where it can heat water tank and also be condensing on CH side so that it saves more money at the end. If I could get PDHW working even better but until now I am not finding any wiring diagram to follow. Cheers

[@HeatGeek]

@BiMi UK 54 return temperature not flow. And the lower below the better. Read our article on it.. Google 'heat geek condensing theory' it's all there

[@MohamedFareedh]

I did this until I got my boiler serviced. The person who serviced my boiler said this is not recommended.

[@felixscamp]

I love these info clips but I wish someone would mention a device called a Boiler efficiency Manager, I fitted one to ours & they really do work by stopping the boiler dry running, saves a few quid please give them a mention

[@HeatGeek]

No idea what that is and can't find it on Google?

[@lorclyons]

Ha so true about showers

[@marloweye9188]

Great proper and practical advice for once. But wait? It's based upon gas boilers rather than silly heat pumps. Is there a lesson to be learnt here?

[@daveofyorkshire301]

The thumbnail is clickbait, it's impossible to reduce your gas bill below the standing charges... and it these charges they've been raising, so no matter how much you cut your gas usage only by disconnecting can you cut your bill below standing charges...

[@grommie]

I turned it down to 45, after maintanahlge it was back to 70 degrees celsius🤣

[@Allegedly2right]

My heat pump has used Zero because it is not switched on it don’t do hot water because it would not fit in my kitchen Heat Heat pump not required in summer,can’t afford to run it in winter haha so it will use zero in winter love it

[@noelburke6224]

Look for a heating engineer that has years of experience

[@marktrewin4726]

The training is crap but don't agree with the comments on air heat pump as its dependent on outside air even ground heat pumps take ages to reach temp and are better suited to under floor heating. i have been working with all types for years biomass CHP heat pump. But with new boilers they all should be using smart stat and use weather compensated as this will save nr 30%. Weather compensation will pay for its self within the first year also the better boilers have a heat store for hot water.