Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
Maintaining temperature on windy day
Hi,
We have a Midea ASHP with underfloor heating throughout and thermostats in each room. The heat pump is running in weather compensation and the temp is pretty well maintained until we have a windy day!
We’ve had a cold snap here and the weather compensation worked well, but today is a little warmer but with a cold wind and the room temps throughout have dropped by 2-3 degrees.
We are in a new build and quite exposed to strong winds. I suspect it’s due to heat loss from poor quality building but I just wondered if there’s any way of factoring the wind in as well as the outside temp?
Thank you
Katie
Not natively to any heat pump or boiler sofaik.
You could try running on WC + temperature sensor (ideally the midea one not third party thermostats, assuming it's sensibly located) and upping the WC a couple of degrees. This will cost a few percent in efficiency and may make room temps less stable (or may not), but with a new build that should be well well insulated hopefully not too much cost.
Other than that it' some third party or home grown tool that harvests the weather info. An anemometer which 'massages' the output of the oat sensor would be an option, or something that interfaces to the modbus. Thats the sort of tinkering that only some people like doing though, and obviously I dont know if you are (or have access to) one of those! @cathoderay has done some add on control for his midea so will be able to advise
What are 'thermostats in every room' doing. Hopefully nothing!
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.
It sounds like you have the 'cold' end of the WCC set up well. What happens if you adjust the 'warm' end so that the temp remains stable on a day like this? Will the IAT massively overshoot when a little warmer but not windy?
We're near the south coast so quite windy as well, and not particularly well insulated. Our midea WCC has been coping ok, with IATs between 20.5 and 22. Just wondering if it a case of accepting some variation but primarily setting up the WCC so that it doesn't drop below min comfort level? The main annoyance I have with the midea is that any adjustment of the WCC settings turn everything off (utilising modbus connection to alter these remotely via home assistant) thus my general approach has been to try and leave it so I don't have to fiddle with it. As alluded to above, Cathoderay seems to have nailed this with their controls set up and that automatic adjustments to the curve in serviceman settings based on IAT under or over shooting, does not do this.
Posted by: @jamespa@cathoderay has done some add on control for his midea so will be able to advise
"done some add on control"??? It's a most elegant solution, might I remind you!
Seriously, it is not complicated, and uses the indoor air temperature (IAT) to adjust the weather compensation curve (WCC). It (it is a python script) could easily be adapted to factor in other things like wind speed as long as you have current wind speed data but I am not sure that is necessary, because the IAT is the product of all the factors acting on it. If the IAT drops because of wind chill, all we need to do is have the control set up respond to the drop in IAT, we don't need the wind speed to do that, although it is probably the case that reacting to wind speed might make the response a bit faster than waiting for the IAT to drop.
The prerequisites for making it work are something that can run python connected over modbus to your wired controller. You then just let the python script run all the time in the background. In my case, it checks the actual IAT against the desired IAT once an hour, and if there is a discrepancy, it moves the WCC in opposite direction ie if the IAT is too low, WCC gets moved up, and vice versa.
I can supply more details if anyone wants to put this into practice.
Midea 14kW (for now...) ASHP heating both building and DHW
Posted by: @cathoderay"done some add on control"??? It's a most elegant solution, might I remind you!
Of that I have no doubt and apologies for any offence!
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.
@jamespa — now that you have done some add on apology, honour is restored.
Midea 14kW (for now...) ASHP heating both building and DHW
Valiant & Daikin have a form of load compensation or room influence which can dynamically adjust the WDC by a few degrees based on what thermostat is reading. Have search for that feature.
@jamespa thanks so much for your reply- unfortunately the Midea temp sensor is located in with the water tank but I’ll have a little play with adjusting the WC!
@cathoderay thanks for your reply! That sounds amazing but a bit over my head!! Do you do home visits 😝
@radwhisperer thank you. I’ve just found that but the temp sensor on the controller is located in with the hot water tank, and with thermostats in every room of the house I have no idea!!
Posted by: @curlykatieDo you do home visits
I used to, but now I am retired. Mostly I miss doing them, but I will never forget a GP trainee in a rough neighbourhood telling me the trainee on a two week placement to 'stick my doctor's bag through the door first, so the rottweiler bit it and not me'!
The python script approach I use is a bit geeky as @jamespa rightly implied when he done some comments, but the idea can be applied manually. If you know there's a beast from the east on the way, set the WCC two degrees higher (via the FOR SERVICEMAN menu) and then take it down again when the beast has gone through.
Midea 14kW (for now...) ASHP heating both building and DHW
- 27 Forums
- 2,775 Topics
- 65.4 K Posts
- 4,090 Online
- 7,180 Members
Join Us!
Installer Finder
Degrees of Separation
Latest Posts
-
RE: Is it just me, or does tradesperson timekeeping and communication drive you absolutely mad?
Yes, and I would suggest likely to get worse with more ...
By Batpred , 4 hours ago
-
RE: Electricity price predictions
This topic seems more suitable for this thread... I a...
By Batpred , 4 hours ago
-
RE: Why are ASHP installs so expensive?
It is clearly difficult to say, there must be cases whe...
By Batpred , 4 hours ago
-
RE: Who's your electricity provider and what's your tariff?
Hi all, I'm new to this game having spent the last 25...
By gz00 , 5 hours ago
-
RE: Panasonic Free Multi Z and Etherea Internal units.
@dgclimatecontrol Thank you for that information and re...
By Toodles , 9 hours ago
-
RE: My Kronoterm Adapt 0312 ASHP is finally installed!
@editor It was serendipitous really. Both my wife and I...
By tomasmcguinness , 14 hours ago
-
@mrkfm, I'd also suggest that whenever you're ready, st...
By Mars , 1 day ago
-
RE: Are you planning to use a wood burner to supplement your central heating this winter?
I use my stove daily for backup and comfort. Definitely...
By Margarethomas , 1 day ago
-
@rob-of-york Thanks. I wish I'd started on this site as...
By mrkfm , 1 day ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@downfield I just checked this morning and OE just r...
By Papahuhu , 1 day ago
-
RE: Passiv Smart Thermostat - Help & Forum Support
Thanks Will. I'll probably be a week or so before get...
By Singlespeed , 2 days ago
-
RE: Cooling using an air to water heat pump
From experience this summer, a single-split A2A unit on...
By Rob of York , 2 days ago
-
Analysis of the economics of switching to an A2W ASHP compared to other heat sources
This post aims to analyse the economics of installing, ...
By Rob of York , 3 days ago
-
RE: Cooling with air to water heat pumps
@editor does that mean you have to have two separate ex...
By mrkfm , 4 days ago
Members Online
No online members at the moment




