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.
- 26 Forums
- 2,158 Topics
- 47.4 K Posts
- 51 Online
- 5,736 Members
Podcast Picks
Latest Posts
-
RE: Who’s Caved and Switched the Heating On Already?
Central heating still switched off and will be until Oc...
By AllyFish , 2 minutes ago
-
RE: Heat Pump Servicing & Maintenance – Good Value or Rip-Off?
Our 1st Octopus heat pump service just completed. He ...
By NJT , 3 minutes ago
-
RE: Is a Valliant Inline 6kW heater a BUS buster?
I think the problem you are having comes down to the un...
By JamesPa , 29 minutes ago
-
RE: COP is not the only measure of efficiency
We keep all our TRVs fully open using the whole house a...
By Old_Scientist , 44 minutes ago
-
RE: Midea ASHP – how to set weather compensation
I think it is a bug in the code, it comes on even when ...
By cathodeRay , 15 hours ago
-
RE: Havenwise App Help & Forum Support – Get the Most from Your Heat Pump
I am pleased to say at 4pm today we have added another ...
By ASHP-BOBBA , 16 hours ago
-
RE: Buffers, hot water and cooling
@jamespa Your reasonably close! Especially with warmer ...
By dgclimatecontrol , 18 hours ago
-
RE: Renewables & Heat Pumps in the News
To unpack this a little.... 1) how many of us in this...
By Lucia , 1 day ago
-
RE: Vaillant aroTherm Plus 10kW thoughts?
@realevil the fans and fan speed / coil size (height, w...
By ASHP-BOBBA , 2 days ago
-
RE: Mitsubishi Ecodan 11kw Defrosting Issue.
@morgan this can just be done by your sepecilist when t...
By ASHP-BOBBA , 2 days ago
-
RE: Anyone still weathering it out with Agile?
@toodles I guess it all comes down to import averages. ...
By Tim441 , 2 days ago
-
RE: 300 Liter Tank - Do I have to heat it all?
The size of DHW tank affects the anti-legionella cycle....
By Transparent , 2 days ago
-
RE: Heat Pump SCOPs – The Truth Might Not Be What You Think
@scalextrix Name plate capacity
By HCas , 2 days ago
-
RE: Solar Thermal DHW and ASHP
I was originally contemplating a solar thermal installa...
By jamespetts , 2 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
My system installed in July 2024 has produced 6.4mWh in...
By jamespetts , 2 days ago
-
RE: A Customer's Lessons Learnt from a Heat Pump Installation in a Large House
@judith thanks for your suggestions. Starting from col...
By GrahamF , 3 days ago
-
RE: Inventor (Midea) Heat Pump short cycling advice
I switched to "fan coil mode" to be able to set water t...
By immunity , 3 days ago
-
RE: DESNZ doing a survey which asks the right questions!
Without a survey their only source of data is probably ...
By JamesPa , 3 days ago
-
RE: Can you help with our research: solar panels, EV chargers, home batteries, heat pumps?
Just done your survey!
By Judith , 4 days ago