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Last seen: Mar 23, 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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