400% Microbore 3 Port Buffer Tank Heat Pump

[@deanchapple1]

The information on the EPC is wrong…..

[@JamesRattray]

Thank you for highlighting this. According to the Government website, in order for your property to be eligible to apply for the BUS, you need an EPC with no recommendations for cavity wall insulation or loft insulation. This is a quote and link to the GOV website "Your property must have a valid Energy Performance Certificate (EPC) with no outstanding recommendations for loft or cavity wall insulation. with no outstanding recommendations for loft or cavity wall insulation." Apply for the Boiler Upgrade Scheme: Check if you're eligible - GOV.UK (www.gov.uk) When Ian was saying this, I did put a caption on saying check the Government web site out for info. But you are right, Ian's interpretation was not as above.

[@deanchapple1]

It’s now changed……. And it was never that it had to be a ‘C’……

[@895522]

@@deanchapple1 I had the C requirement in my head. In retrospect it may have been an installer who mentioned that they wouldn't install a heat pump in a house with anything less than a C.

[@mooobymoof]

I connected the monobloc to the nearest heating pipe in the floor at 40 CM inside and used the circulation pump of the monobloc for the whole open heating loop and used a buffer tank in the return pipe for defrost volume ...so just 1 pump en get rid of the legacy from the old boiler design

[@hughrattray9354]

My system is similar to yours - the buffer tank in the return pipe is effectively a volumiser. The good thing is that you can get good efficiencies with a direct system, like yours, but also with a 3 port buffer if you need one.

[@jsimnable]

good to see! I just had a system very similar to this installed. In North America, 3-port buffers are being recommended/gaining traction for heatpumps, but the mixing happens at the bottom. Its the top that has one port, so highest temp flow goes straight to emitters without mixing.

[@JamesRattray]

Very interesting, thank you for sharing this with us. We are always keen to hear heat pumps are evolving in other areas of the world.

[@lovegunsdude]

Which way do you think is more efficient? James' or the North American one?

[@stevenm45]

A very interesting & helpful video. Many thanks for taking the trouble to share your heat pump experience & enthusiasm with us.

[@hughrattray9354]

Excellent video. Really useful insights into the three port buffer system through the extra monitoring you have installed.

[@redshift3]

I like the way that the buffer tank uses only 3 ports to minimise mixing

[@UpsideDownFork]

Just here being a pedant. Dont mind me. You don't need an EPC of C or above. Full weather compensation without room influence doesn't use the sensocomfort thermostat to affect the flow temperature in any way. Very interested to see the comparison of buffer vs no buffer. I've seen plenty of 4 port buffers, but not any 3 ports. Great extra data collection you're doing pre and post buffer 👍 How long are the 10mm drops? Do any of the radiators require over 1000W? Great video, thanks for sharing!

[@895522]

Thanks for the comments. When I started the HP project a EPC of C or above (+some other specifics) was required. Since then the rules have been changed/relaxed. You're of course right, weather comp doesn't use the internal T. The 10mm drops vary in length, but I'd say the longest is probably around 5m. None of the radiators are over 1000W. The biggest is 855W.

[@UpsideDownFork]

@@895522 thanks for replying 👍

[@giuseppe072000]

What model is your secondary water pump? Is possible to change flow rate to be at maximum when is defrosting? Your heat pump is possible to control second water pump/ module ?

[@alanclarke4965]

Interesting to see 3-port buffer, but it does seem to make clear that the return to the ASHP is same temp as rad return, so ASHP flow is that + 5 degrees, however if rad pump is running faster than the ASHP circ pump then this temperature is being mixed down to result in radiators lower temp than if plumbed direct from ASHP (ie to me this 3-port arrangement isn't helping with efficiency of heat pump over 4-port)

[@lovegunsdude]

Do you think that the North American setup of 1 port at the top and 2 ports at the bottom would be better?

[@Bandits_At_3_o_Clock]

Thanks for this video because I’m planning a similar project. Are your replacement radiators the same width as original and then adjusted for height and either k2 or k3 to achieve required heat output? What is the maximum required heat output of any radiator in your system?

[@895522]

Most of the old radiators were either Type 11 or 21. To achieve the power output they all became Type 22 (apart from the towel rads in the bathroom) and we used taller rads (in every room we had space for this). Aside from some tidying up of the pipework around the radiators they all fitted into the same width. The maximum output from any rad is 855W.

[@lovegunsdude]

I'm looking of having my standard 4 port buffer system changed to a 3 port buffer (bad COP). Not yet sure if having this system or the american system with one port at the top would be better. What do you think?

[@nickflynn666]

kzbin.info/www/bejne/q2nMoWCYitSigJIcop 4.14 at 5C sounds very good to me. Interesting that the boost in cop is only 0.2 with an extra 5C outside temperature I'm beginning to see why some people rave about the efficiency benefit of not over sizing the heatpump, the ability to run continuously at a lower output being significant. I wonder if in the future we will have better inverters or other methods to allow an even greater range of continuous outputs: the ability to never have to cycle on and off seems like a good way to even further improve the cost benefit of heatpumps over any other heating system.

[@hughrattray9354]

I wonder why heat pumps modulation range is not greater - do you know? The Vaillant can run at a minimum of 25% of output. Why can't it run at 10%?

[@andreycham4797]

For those who did not do such an install he showed a middle finger

[@Simpleboneguy]

Did you get a heat loss assessment and upgraded insulation etc?

[@895522]

My journey to the heat pump installation took place over several years and included additional loft insulation (minor improvement) and new windows (massive improvement). I observed the house heat loss using a borrowed infrared camera to check for hot, leaky spots (I still have an area I need to improve). I also assessed the heat loss using the "Heating Degree Day" methodology and in-room calculations based on the construction and window thermal conductivity values. Finally, the EPC assessment was done and this confirmed the house was well enough insulated to get the best out of a heat pump (it got a high B).

[@iainbusbridge9585]

Who was the installer?

[@895522]

My installer was Swift Renewables out of Clevedon, Somerset. I am happy with the work they did and have recommended them to others.

[@ricardopelc-wesoly3483]

So many conflicting views on using microbore, who's educated enough to explain why!

[@hughrattray9354]

There are two good examples of microbore systems working well on this channel. One with a buffer tank and the other without. The key issue is to make sure you have adequate flow rate. Both the systems here have 22mm backbones with 10mm radiators plumbed in parallel to each radiator.

[@TheDickPuller]

@@hughrattray9354Not really the most important thing, 10mm has a limited Heat Carrying capacity, so it’ll limit the size of the emitters. Which for a Low Temperature system is not good. Also, regardless of fitting a buffer or not the F&R Delta T is very important & again with 10mm tube, it’s limited.

[@lumbarsupport]

@@TheDickPuller I have an 11.2kW ASHP with 16 large radiators all using 8mm microbore and it works extremely well. It uses a small low loss header in 3 port config, with the microbore circuit supported by a secondary pump, the return bypassing the LLH and connecting directly to the primary return. Average flow temps rarely get above 40degC and COP average for Oct'23 to Mar'24 was 4.2, for heating and hot water.

[@TheDickPuller]

@@lumbarsupport Has s your CH circulation pump running like a Steam Train too??!!! My guess is the circulation through these Microbore tubes are a huge velocity!.......These circulation pumps will not last very long. Plus, you must be telling Porkies, as your figures don’t compute. So don’t talk 💩, I’ve been in the CH game for 50 years & you beard stroking, tree huggers talk drivel! Just listen to the two old farts in the video, Sanatogen Sid & TCP Pete😂😂😂😂

[@SoullessAndSynthetic]

But the one big question nobody answers…..based on what it cost to install…what is the ROI….how long until it pays for itself. From my calculations it’s 20 years or more……makes it a hard sell (especially to the wife)

[@JamesRattray]

What is the ROI on a gas or oil boiler….how long until it pays for itself?.