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Last seen: Mar 23, 2026
@mike-patrick I couldn't agree more. It might be the case that, eventually, given lots of tweaking and work by the home owner, you get decent performa...
@mab Sadly, lower temps aren't helping me at all - entered the night at -7C and left at -2C. I tried dropping target LWT yesterday (the theory being...
@mab I've done some brief analysis of some minute-by-minute data and the defrost cycles seem to be around 40-45 minutes apart, possibly triggered by t...
@iancalderbank Yes, that's something I'll be looking at. But I'm trying to hold off changing any WC parameters until I've sorted out the flow rates / ...
Ditto here. I can just about keep the house at 19C, but the pain of getting a 1C increase from an overnight setback takes at least 3 hours of daytime,...
Yes, that certainly isn't wired as Grant want it to be. Zones 1 and 2 are wired together (which isn't that unusual, if somebody wants both zones to op...
@mab I must admit, I've never looked at the state of the fins. Too bl**dy cold to be outside. I'm just assuming all is working okay. I would have thou...
@mab As far as I can see, (at least for the Grant) there's no 'user control' of the defrost cycles (maybe wisely). The 'defrost temperature' is poorly...
@ghayne @allyfish I think I agree; the OAT seems fairly resilient to what the HP is actually doing (I get a bigger influence from sunshine with HP on ...
@marvinator80 You can see the LWT (and Return WT) on the Controller. Slightly easier than getting to the other parameters, you press the 'return' key ...
The optimal figures will be different for each house, but those figures don't look wildly out. 21 01 is the fixed LWT (leaving water temperature); s...
@allyfish Ditto for my Grant 10kW - it gets closer to the target LWT after each iteration following the defrost cycle, but never seems to quite make i...
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