That’s something we can address in my opinion. It’s not rocket science, we know everything about the physics involved in heating a building. We should embed that knowledge in our heat pump controllers.
But do we know the effect of strong wind?
My critical room (living room) is very exposed (3 outside walls and half the ceiling flat roof) and simple weather compensation - based simply on external temperature - just doesn’t cope when it’s windy on the exposed sides. (I estimate the OHTC is 10-15% higher than the zero wind case.) So I need 1-2degC extra on LWT to compensate.
Having said that, I’ve also found that simply drawing the blinds and (heavy) curtains reduces heat loss by a similar amount, and I don’t suppose that anybody is about to programme that into their algorithms…
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Yes we do. But the effect is highly non-linear so it’s difficult to predict the heat loss resulting from wind. Small neural networks may help in this regard, I am still investigating the feasibility of that approach.
No definitely not. However at each new time interval the heatpump will see the difference between its predictions and reality, and correct for it similar to how a PID controller would work.
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Remember many of these proprietary room controllers are optional, and without them the choose is pure weather compensation or fixed flow temperature.
But we also know there is zero incentives for heatpump makers to improve the control software for existing customers. And there is little incentive for them to care aboug performance outside of the standardised energy rating tests.
There are definitely incentives to do so, because you can advertise with that feature. I don’t know how other HP manufacturers handle this but Intergas provides updates via FOTA, so as long as it’s connected to wifi you’ll get all the latest updates.
This is my third year with a simple Midea ASHP, but first with Octopus Cosy. I also have battery and solar. I also set the flow temperature down to 35/36c back in October and have not looked back since. The pump just runs without cycling as long as outside is above 2C. Below 2c defrosts between 40-50 min.
During Cosy times the three thermostats are set to 22c mostly to avoid any zone turning off. In between the setback is to mostly ensure the heating is off at night (18/19c) and outside Cosy cheap periods. In the day I bring all three zones on after 9am when there may be solar to use (the battery/inverter round trip efficiency is in the low 80% region while solar gives over 95%) and the air temperature is conducive to the COP being 4-5 (2c gives 3.7). As soon the outsize temperature is likely to remain freezing all day I switch to constantly on. I don’t have continuous COP monitoring and averaging just the reported heat output and electrical power.
The only improvement I am considering is fitting fans under the rads to boost output in the cold weather without increasing the flow temperature. The HP tends to run about 50% capacity based on monitoring return temperature relative to flow (4c difference rather than 5c). I have a heat exchanger so some control of the secondary pump flow rate might be beneficial coupled with some room and outside temperature sensors.
Phil