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Last seen: Sep 6, 2026
Primary flow rate is good. Now it's time to sit back and stop thinking about deltaT, low loss headers, thermal mass, heating zones, ... have a break, ...
Has the flow rate now increased if you look at the regulator below the pipe where the mag one sits? Balancing the flows across the LLH is something ...
Isha killed my internet so out of loop a bit on this one, but has the auto bypass valve been checked? It should be set to almost never operate as your...
I think Grant have recognised how unfriendly the controller is, with bringing out (soon) there own 'smart' controller, but I'm not expecting this to b...
@crimson So far as I understand it, before the plumber started fixing things (i.e. when you had the blown DHW controller) most of the CH zones were wo...
Your conclusions (1) and (2) are probably valid, and common for most ASHPs it seems - the defrost cycles nobble performance, as although they only tak...
The standard flow regulator which comes with the Grant (and I think yours looks like one), you read from the bottom of the float, so 29l/m if I can se...
If you can get them to focus on the flow rate, which seems to be the main issue. Playing around with the HP parameters is really tweaking to help with...
As @allyfish has pointed out, that flow rate is an issue - the 'square-headed' screw-like thing below the gauge window on the regulator is what contro...
@editor Confirmed. Just got the notification for this mention. Thanks 😀
@crimson A = Secondary circulation pump B = Magnetic filter C = Low Loss Header D = Flow Regulator? E = Diverter Valve? The question ...
The problem with looking at the flow and return temps on the controller is that they are constantly changing, so it might look good at one moment (and...
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Latest Posts
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RE: Next steps on my ASHP journey: Radiators and Pipework
If you are considering phasing the project, then I woul...
By GrahamF , 3 hours ago
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RE: Siting of the external sensor on a heatpump
Of course had the heat source been a heat pump it would...
By JamesPa , 5 hours ago
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Never assume, it makes an ass of u and me! OK, tha...
By JamesPa , 5 hours ago
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RE: Recommendations in Ely (Cambs) area for Full setup checks on Nibe HP setup for House.
In fairness all heating has cost a lot to run in recent...
By JamesPa , 7 hours ago
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RE: Is it the house or the equipment?
@springswood We have two Daikin single split A2A syst...
By Rob of York , 8 hours ago
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RE: Navigating the World of Refrigerants In Heat Pumps: A Guide for Homeowners
Indeed we are invvestigating AC at present and are havi...
By Toodles , 1 day ago
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No, but the heat pump must be capable of delivering a S...
By JamesPa , 2 days ago
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RE: Daikin ESPAltherma and Home Assistant installation
It's laziness lol The PV system is very chatty, meter...
By bobflux , 2 days ago
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RE: Problems with sizing a replacement for a Viessmann Vitocal 200-S
R (The R Project for Statistical Computing, I use it wi...
By cathodeRay , 2 days ago
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RE: Vaillant Arotherm Plus 7KW need a service on it
booked it with Vaillant. will use them until i can find...
By AdamK , 2 days ago
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RE: Adventures in heat loss calculations
I have seen it stated that the declared calorific value...
By JamesPa , 3 days ago
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RE: Two heating zones to one zone
@transparent Many thanks. The garage is fairly well ...
By Profzarkov , 3 days ago
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RE: Vaillant Aurotherm - Heater Wire Position
Ah, good point. I need to check if this was installed i...
By Batpred , 4 days ago
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@batpred thanks for getting a copy. Appreciate the supp...
By Mars , 4 days ago
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