What happens during the transition from winter to summer with your heat pump?
just curious as obviously if i go down the route of weather comp open loop system setup, which most seem to say is the most efficient, what happens as the weather warms to the point where the house needs less and less heat to maintain 20c say? surely you get to a point where the HP starts cycling as it can no longer modulate down any further, and conversely as autumn approaches when it starts to need more heat.
as ive watched lots of HG and QA vids but most talk about the other end where its maybe -3 and getting to the limit of the HP maybe.
You are correct the heat pump will cycle on and off at any temperature if it cannot modulate down far enough to maintain the flow temperature. Open loop gives the system the best chance of delaying that point by having the maximum amount of water engaged and no rads or ufh zones shut off.
This is when a simple on/off thermostat is useful as the house will get to temp and then shut off the heating till the thermostat calls for heat that could be hours later.
Cycling is only bad for the heat pump compressor when you are stopping and starting multiple times an hour, how many is acceptable is debatable but multiple stop/starts are bad.
My system will go down to 25C flow temp but it won't go below 32C flow without cycling 2/3 times an hour so I don't run it lower than that.
You should also be able to set an outside air temperature at which the system will turn off.
- 22 Forums
- 2,036 Topics
- 44.4 K Posts
- 17 Online
- 3,239 Members
Join Us!
Trusted Installers
Struggling to find a reliable heat pump installer? A poor installation can lead to inefficiencies and high running costs. We now connect homeowners with top-rated installers who deliver quality work and excellent service.
✅ Verified, trusted & experienced installers
✅ Nationwide coverage expanding
✅ Special offers available
Latest Posts
-
RE: The Rise and Fall of Europe’s Most Generous Green Subsidy
@dwynwen welcome back… and glad to hear you made it thr...
By Mars , 9 hours ago
-
RE: Air Source Heat Pump - Side Alley Suitability
@ad3628 I’ve seen loads of heat pumps successfully inst...
By Mars , 10 hours ago
-
RE: Hitachi Yutaki SCombi Heat Pump - Thermal Off's
@trebor12345 The Auto function is supposed to adapt au...
By Heatgeek , 12 hours ago
-
RE: In the middle of an ASHP installation - a few questions (and issues)
@jamespa they didn't provide any contract, or design pr...
By benson , 15 hours ago
-
RE: The Great British Heat Pump Quiz
@allyfish thanks for the feedback and glad it was fun! ...
By Mars , 17 hours ago
-
RE: help sizing rads based on room by room heat loss
If its 1988W at DT 50, which is how most radiators are ...
By JamesPa , 22 hours ago
-
RE: Career change – entering the world of heating and heat pumps
@editor Mars, thank you. That's along the routes I was ...
By Lakey , 22 hours ago
-
@editor thanks Mars, it's a rare occasion I'm looking f...
By big_si , 1 day ago
-
RE: Efficiency Concerns on newly installed Mitsubishi Ecodan 8.5kW
@ashp-bobba and @jamespa - thank you both for all your ...
By CBrenewable , 1 day ago
-
-
Win one of five "Heat Pumps 101" Courses
Heat pumps are gaining traction in the UK, but between ...
By Mars , 2 days ago
-
RE: Agile: average import cost vs other tariffs?
@toodles thanks for the analysis. I'll be really intere...
By Old_Scientist , 2 days ago
-
RE: ASHP Ecodan L9 error - No Heating but Hot Water
@phoenix15 I'm no plumber so please don't take this as ...
By dnagre , 2 days ago
-
RE: Is this normal? Click of the DHW returning to space heating
@grantmethestrength Oh sorry to hear that, there should...
By ASHP-BOBBA , 3 days ago
-
@ashp-bobba TBH the ladies are rather disorganised, so ...
By Cathyem1 , 3 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
And for those of us without an automatic irrigation sys...
By Majordennisbloodnok , 3 days ago
-
Logically, the lower frequency = more gentle, yes, but ...
By SUNandAIR , 3 days ago
-
RE: Ideal Logic ASHP - change from 55°C to 35°C Heating?
Good point. I’ll keep my eye on the manifold temperatur...
By Tomdad , 3 days ago
-
RE: How hard and expensive would it be to change panel and add battery?
@transparent It is a setting that Octopus make via the ...
By Toodles , 3 days ago