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: May 5, 2026
@cathoderay - thanks for an interesting discussion! The heating/building industry doesn't but science/engineering isn't so limited. Modelling heat t...
It's close enough to steady (+/- 35W) to get reasonably accurate steady state values, that can then be used to calculate what happens if something hap...
@travellingwave Ah yes, that would explain it.
@travellingwave A straight line like that in recorded data could be from a sensor problem, maybe OAT? Yes, the other points are suggesting 8-8.5kW ...
@travellingwave You don't need to record IAT to use the tool, if your IAT is usually 20C then as the tool defaults to 20C you shouldn't need to cha...
Hi @travellingwave If your system is on heatpumpmonitor.org then a chart similar to what @cathoderay is suggesting is already available. If you go ...
True there is a variation but importantly it's understandable. The ~560W value occurs before a defrost at 5C and so the ~560W is at the colder end of ...
@cathoderay The input power is largely determined by the compressor speed (it's by far the largest component) and that is set by the controller alg...
Or part of a cycle like a defrost or ramp up. Being able to set an arbitrary interval gives the greatest flexibility and doesn't preclude the use of h...
Hi @cathoderay This is a reply to two of your posts together. It's not a room stat per se but acting as one at the moment and its use...
Hi @sunandair I've posted charts showing the input power ramping up to the same 1-1.5kW in both (defrost and non-defrost) cases. Your image doesn't...
Hi @sunandair The analysis I previously posted was 90+ minutes long and not just 11 minutes. All of the electrical energy passing into the system go...
Latest Posts
-
RE: Renewables & Heat Pumps in the News
An article on funding for heat pumps in case anyone is ...
By Jeff , 31 minutes ago
-
RE: Indevolt Batteries UK Support & Info Thread
Thanks @editor , @indevolt-uk Subject to any comments ...
By JamesPa , 8 hours ago
-
RE: Share Your Experiences with Heat Pump Manufacturer Support
@seoras Sorry to hear that. I found Vaillant very help...
By JamesPa , 9 hours ago
-
The Watchdog That Watched and Waited
On 9 January 2026, Consumer Energy Solutions collapsed ...
By Mars , 12 hours ago
-
RE: GSHP Kaput After 16 Years: New Compressor or Switch to ASHP? Advice Welcome
Cool Energy in Grimsby sell ground source heat pumps an...
By DerekDeLeon , 13 hours ago
-
RE: Valliant Heat Pump Settings
Thats arguably a sign of a good installer - they unders...
By JamesPa , 14 hours ago
-
RE: Electricity price predictions
Well, we have so many cases where rain water mixes with...
By Batpred , 15 hours ago
-
RE: Two heating zones to one zone
@profzarkov They arent obviously wrong, but the only...
By JamesPa , 17 hours ago
-
RE: Towns water feed to air source heat pump system
The DHW circuit cant be separated (well it could, you c...
By JamesPa , 17 hours ago
-
Solis AC-coupled 3kW storage inverter
Solis AC-coupled 3kW storage inverterPylontech batterie...
By MartinRobinson , 23 hours ago
-
RE: My NIBE ASHP Nightmare: No Commissioning, High Bills and a Hostile Installer
As @transparent has observed above, this is not bad, an...
By cathodeRay , 1 day ago
-
As I was reading this article Mars, I was thinking that...
By Toodles , 2 days ago
-
RE: Tell us about your Solar (PV) setup
Installed in May 2011: 16*Sharp 245 W monocrystalline p...
By txmartyn , 2 days ago
-
-
RE: Say hello and introduce yourself
That doesn't sound 'right' to me. The national Smart ...
By Transparent , 3 days ago
-
RE: Growatt battery disconnected
I doubt this will happen, but I will try and suggest it...
By Eliuccio , 3 days ago
-
Understood. That's why I decided from the outset on a ...
By JamesPa , 3 days ago
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
On the litigation, I would not go there and definitely ...
By Batpred , 3 days ago
-
RE: Recommended home battery inverters + regulatory matters - help requested
I suppose if your pv inverter packs up, you have a plan...
By Batpred , 4 days ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
Firstly check you are using sound power not sound press...
By JamesPa , 4 days ago
-
That’s the solar up and running, I don’t think it’s the...
By David999 , 4 days ago
-
RE: Seeking ideas / information / commiseration - Pure Drive
I agree with @colinc that you can reuse some of it. A s...
By Batpred , 4 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@toodles Im trying me best to ignore orangeman, I figur...
By Papahuhu , 5 days ago
