If I had a new ASHP installed I would still have to have a hot water cylinder. I watched the relevant video on this site. But I don't need any buffer unit.
Can I get clarification on this point.
Can the ASHP External unit, supply heat for Central Heating radiators or UFH at one temperature and one set of F&R pipes and do that supply directly? Bypassing the cylinder?
Or have I got that completely wrong and need to go away and do some serious reading? 🤔
Nothing like a government grant to bring out the bandits for sure. An absolute minefield and as per my other post our current installation is hardly going smoothly. The company we went with however were one of the few who didn't want a massive amount of money (in effect the whole cost of the job minus the grant) up front, so at least I have some leverage to try and ensure it is completed to a decent standard.
As for optimus heating, came across as knowing their onions but I booked an initial home survey after a fair bit of back and forth communications (mainly telling me how good they were) and after all that they didn't turn up or contact me to tell me they weren't coming. Red flag #7?
@benson Optimus didn't turn up?
Get a copy of The Ultimate Guide to Heat Pumps
Subscribe and follow our Homeowners’ Q&A heat pump podcast
@benson that's very disappointing indeed.
Get a copy of The Ultimate Guide to Heat Pumps
Subscribe and follow our Homeowners’ Q&A heat pump podcast
Posted by: @gt22Can the ASHP External unit, supply heat for Central Heating radiators or UFH at one temperature and one set of F&R pipes and do that supply directly? Bypassing the cylinder?
Or have I got that completely wrong and need to go away and do some serious reading?
ASHPs (and fossil boilers running at a low flow temperature or with weather compensation - rare in UK, common in more enlightened countries) supply at one flow temperature at any one time and thus the installation will invariably include a three way diverter valve (or two two way valves) so that space heating or dhw can be fed, but not at the same time. The unit switches flow temperature and the diverter valve according to whether space of dhw heating is required.
If you need, in addition, two flow temperatures for space heating you must supply the space heating at the higher temperature and mix down for the lower. Again same for boilers and ASHPs. The ASHP COP will be determined by the higher, because that is the temperature it is required to produce.
Hope that clears matters up.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Posted by: @gt22
@jamespa Many thanks. You are adding to my education on the current ASHP approach. So different from my 2009 Sanyo configuration, hence my questions.
My ashp journey is only 3 years old and in that time it's clear that thinking has matured quite significantly, albeit by no means universally. I can only imagine how much change there might have been since 2009.
Please continue to ask questions, people here are very willing to help and no question is silly.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Great article! You've highlighted essential red flags to watch out for when considering a heat pump installation. One innovative idea would be to include tips on how to verify the credentials of installers, ensuring both quality and reliability in the installation process. Keep up the informative work!
One innovative idea would be to include tips on how to verify the credentials of installers, ensuring both quality and reliability in the installation process. Keep up the informative work!
@mars That could be a whole discussion in itself. I don't personally think its simple!
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
- 26 Forums
- 2,255 Topics
- 50.3 K Posts
- 229 Online
- 5,918 Members
Join Us!
Podcast Picks
Latest Posts
-
RE: Flexi-Orb Heat Pump Scheme: A Game-Changer for the UK's Heat Pump Industry
I think I would agree with that analysis, in essence on...
By JamesPa , 1 minute ago
-
RE: British Gas Heat Pump Installation Complaint
@steelbadger That's great to know! Thanks for that reas...
By BGNO , 5 hours ago
-
RE: When will fusion be producing energy?
Ai used to be the same. But then it started delivery of...
By Batpred , 9 hours ago
-
RE: Buying large amp bidirectional RCD and RCBO
Ok, but it would be helpful to get a figure. Perhaps as...
By Batpred , 9 hours ago
-
RE: When to use Octopus Intelligent Go tariff with my heat pump and battery
Difficult to be completely prescriptive without more de...
By JamesPa , 15 hours ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@allyfish It was going so well with month after month s...
By Toodles , 17 hours ago
-
RE: Electricity price predictions
As that's an energy issue, it would need the DESNZ to p...
By Transparent , 18 hours ago
-
RE: UFH downstairs and radiators upstairs balancing question
Have you tried turning up the stat and turning down the...
By JamesPa , 19 hours ago
-
RE: Help me keep the faith with my air source heat pump installation
I have the same firmware. I have MyVaillant version HA...
By JamesPa , 19 hours ago
-
RE: Midea ASHP – how to set weather compensation
@pash44pump - thank you
By cathodeRay , 20 hours ago
-
RE: Mediation with RECC, what's your experience?
Welcome to the forums @treewizard and sorry to hear abo...
By Mars , 21 hours ago
-
RE: New build installation query
That accounts for why you start with an overly-high DHW...
By Transparent , 21 hours ago
-
RE: Daikin Altherma 3 / HomeAssistant
I would have thought that (instantaneous) power is a fa...
By JamesPa , 23 hours ago
-
RE: Are We Sleepwalking Into Another Race to the Bottom?
Alright, I concede that the Toyotas are, as you say a v...
By JamesPa , 1 day ago
-
RE: Is it mad to think there should be a minimum SCOP for UK heat pump installs?
Sadly I think it is mad. If the BUS is not granted for ...
By Judith , 2 days ago
-
RE: Who has a V2G EV installation
Perfect, @agentgeorge. I’m always up for some edificati...
By Majordennisbloodnok , 2 days ago
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
Yes but... The evidence is that many heat loss survey...
By JamesPa , 2 days ago
-
What Adam Chapman gets up to in his Spare Time.
Ok, so this just appeared on YouTube (don’t blame me th...
By Toodles , 2 days ago
-
RE: Radiator Sizing Dilemma: Vertical vs Type 33 for Low-Temperature Heat Pump Systems
That's my main concern too. On top of that, I ...
By DREI , 2 days ago





