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!
Last seen: Nov 3, 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...
SPONSORS
Degrees of Separation
Latest Posts
-
RE: Should I change my cylinder when changing from a gas boiler to a heat pump.
@jamespa Thanks for the replies. From a ROI perspec...
By David , 15 minutes ago
-
If it no longer works after forgetting its settings and...
By bobflux , 34 minutes ago
-
RE: Heat Geek Zero Disrupt: Are We Sleepwalking Into Another Race to the Bottom?
The Heat Geek survey and design process continues to ge...
By L8Again , 4 hours ago
-
RE: Plug and play solar. Thoughts?
Impressions so far from the one I've installed are that...
By EtchedPixels , 14 hours ago
-
-
RE: Air source heat pump roll call – what heat pump brand and model do you have?
@editor And as an occasional contributor, may I say wel...
By Toodles , 20 hours ago
-
RE: Should Households Who Can Afford It Pay More for Energy to Help Those Who Can't?
They don't have to try. Our entire system is d...
By EtchedPixels , 20 hours ago
-
RE: Why don't people choose heat pumps?
Fair enough. I guess I was thinking of pipes that run ...
By JamesPa , 20 hours ago
-
RE: How Can I Prove Coal Was My Main Heating Source Without Receipts?
Got excepted for the grant now so thanks for the replie...
By Chilli304 , 1 day ago
-
Daikin Altherma 3 R F+W, room thermostat control, weath...
By JanHarley , 1 day ago
-
RE: Buffer tank on a 2 x 14kw Ecodan system
Pretty much as I had guessed in my crude scaling from m...
By JamesPa , 1 day ago
-
RE: Help me keep the faith with my air source heat pump installation
Well you have a vibration generator running at some fre...
By bobflux , 2 days ago
-
RE: Who's your electricity provider and what's your tariff?
@downfield Thats a decent rate, I’m shocked they hadn...
By Papahuhu , 3 days ago
-
RE: Adventures in heat loss calculations
@toodles thanks! So as suspected, around a doubling of ...
By SusannaSaunders , 3 days ago
SPONSORS
