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Last seen: Aug 24, 2026
@jamespa There are two 22mm flow and two 22mm returns shortly after rising from the heat pump where 25mm composite material pipework is used. I think ...
@jamespa Hello James and thanks again. The rads are connected in parallel and there are two runs of 22mm running down the sides of the house, in the...
@jamespa Thank you James, both for the comments and removal of my post made in error. Before answering your questions I think I should say that the...
@jamespa Thanks for your comment James. Of course you are correct and I think I was suffering a little brain fog in suggesting that the pumps were bot...
With the input from @f1p and @jamespa I am persuaded that my problems are all related to low available flow rate, particularly as I have a record of a...
@skyecraig Many thanks. Could you please describe where we are after carrying out any mods and what is necessary to restart?
Back working again now and problem was air in system. Flow rate is 17 l/min Answer to question re flow rate put to Mitsu UK (Portugal is useless): ...
@f1p Yes understand that but why. Investigating air in system
@jamespa Regretting I attempted this now. A very small amount of dirt in the filter, but L9 error now and won't start.
Is this a cross post with someone elses suggestion? I'm not sure we wanted to - i haven't checked the Hydrobox schematic as to see if there is a zone ...
@f1p I would appreciate some clarification on a few points: 1 At time of forwarding the Detailed Report the pump setting was 3 and the f...
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Degrees of Separation
Latest Posts
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RE: Siting of the external sensor on a heatpump
My Octopus electrician (part of the installer team) not...
By Jancold , 1 hour 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 , 1 hour 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 , 2 hours ago
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RE: Next steps on my ASHP journey: Radiators and Pipework
You should (almost) always reject having a buffer, by w...
By JamesPa , 1 day 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 , 1 day 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 , 2 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 , 3 days ago
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@batpred thanks for getting a copy. Appreciate the supp...
By Mars , 4 days ago
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