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: Jul 9, 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: Electricity price predictions
@papahuhu Groucho Marx had something to say about no...
By Toodles , 24 minutes ago
-
RE: MCS Quality Audit – Has Anyone Had One? Did It Lead to Remediation?
Resurrecting an old thread. I got a call from MCS this ...
By L8Again , 39 minutes ago
-
RE: Samsung heat pump - data cable issue
So are Samsung refusing a warranty replacement on the b...
By Old_Scientist , 51 minutes ago
-
Given the way radiation and convection effects don't wo...
By Majordennisbloodnok , 3 hours ago
-
-
RE: Octopus Cosy Heat Pump Owners & Discussion Thread
@jamespa haha very true, although the engineer yesterda...
By swwils , 6 hours ago
-
RE: Vaillant Arotherm Pro vs new Plus
One of the test modes in the installer menu forces it t...
By JamesPa , 19 hours ago
-
RE: What a difference a few degrees make.
Wow. Having accepted the challenge, I ran the cold tap ...
By Old_Scientist , 22 hours ago
-
RE: HeatPump maintenance in Swindon area?
@vince31 have you tried using our finder:/p>
By Mars , 23 hours ago
-
Looking for beta testers for a new homeowner heat pump tool
Over the past few months I've been building a brand new...
By Mars , 23 hours ago
-
-
RE: Indevolt Batteries UK Support & Info Thread
It depends on how you configure it via the app. The ma...
By JamesPa , 1 day ago
-
RE: Renewables & Heat Pumps in the News
Be interesting if this results in any wider changes to ...
By Jeff , 2 days ago
SPONSORS
