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Last seen: Mar 16, 2026
There sure is, but it's not the most rewarding work going round sorting out other folks' cock-ups. If there's one thing I've learned on my domestic AS...
The refrigerant side of the ASHP plate heat exchanger is a condenser, superheated refrigerant gas in at the top, lower pressure sub-cooled liquid out ...
@dodgyknee - yes, Grant controller is a CH and HW thermostat. Not a very user friendly one, and very complicated to work. It's capable, with features ...
On the Grant system you can either turn the ASHP controller off, but that also turns off the timed hot water boost. Or turn the 3rd party thermostat o...
@iancalderbank Yup, tried that, but the tank maxes out at 55degC indicated on the cylinder. The immersion thermostat cuts in and it then cycles on tha...
@derek-m thanks. The immersion heater thermostat on Grant cylinders is pre-set to 65degC and it cycles on/off on that. However, the separate cylinder ...
Much of the struggle with ASHPs in winter is the defrost method. ASHP Evaporator coils have very narrow fin pitch, 1 to 1.5mm. That gives a large surf...
You may need a mains pressure regulator on the cold water inlet to your house. The pre-plumb cylinder inlet manifold has a 3bar pressure relief valve ...
This is interesting @sunandair. The basic weather compensation, relying solely on instantaneous outdoor dry bulb temperature, is crude. I've wondered ...
This is interesting @sunandair. The basic weather compensation, relying solely on instantaneous outdoor dry bulb temperature, is crude. I've wondered ...
@marvinator80 it does this with my 10kW. Algorithm within the ASHP as it monitors air and return water temperature. It’ll turn the ASHP off for a leng...
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Latest Posts
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RE: Seeking ideas / information / commiseration - Pure Drive
@jamespa Thanks - I'm OK with having part of the house,...
By Little Lights , 48 minutes ago
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RE: Home energy storage & battery register
AC coupled Pure Drive 10kW battery Solar PV Solis P...
By Little Lights , 2 hours ago
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RE: Octopus Cosy Heat Pump Owners & Discussion Thread
@swwils I guess the true test will be November/December...
By Mars , 2 hours ago
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RE: Rate the quality of your heat pump design and installation
@claireisamazing, that’s got to be one of the most posi...
By Mars , 2 hours ago
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Got myself in a pickle. I have two types of plugs, but ...
By David999 , 3 hours ago
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@jamespa Great, thanks - I've had a quick look at the a...
By Little Lights , 5 hours ago
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RE: Air source heat pump roll call – what heat pump brand and model do you have?
Forum Handle: ispookie666 Manufacturer: Vaillant Mo...
By ispookie666 , 5 hours ago
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RE: A2A vs A2W: Which Heat Pump Would You Pick?
I'm fairly new to the forum and have not voted. Back...
By ispookie666 , 5 hours ago
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I am seeing an increasing number of occasions when my G...
By DavidAlgarve , 7 hours ago
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@transparent I have been a little reluctant to select "...
By DavidAlgarve , 7 hours ago
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RE: End-of-Life Heat Pumps: How Do You Dispose of an ASHP in the UK?
@editor Thanks Mars. I look forward to the subsequent ...
By DavidB , 12 hours ago
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RE: Anyone concerned about GivEnergy?
Fair enough. Its interesting that opentherm (for boil...
By JamesPa , 12 hours ago
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RE: Brand and installer questions for ASHP
A tank solely in the return (upstream of where the retu...
By JamesPa , 12 hours ago
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RE: UK DIY Battery: SEPLOS 48V 200Ah x2 + Sunsynk 8K – Safe Installation for Garage Conversion
thank you to all who have already replied. I have been...
By madsid , 13 hours ago
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RE: Home automation and the cloud; is there a better way?
+1 It's not just cloud though. Many devices have repla...
By bobflux , 1 day ago
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RE: Summer usage. Why is my Vaillant Aerotherm using so much energy on "heating"?
So the red bars are 'DHW' and the yellow bars 'heating'...
By JamesPa , 1 day ago
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RE: Indevolt Batteries UK Support & Info Thread
Have you tried cutting the grid feed to see what actual...
By JamesPa , 2 days ago
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Contractors pack for inta antifreeze valves are around ...
By ASHP-BOBBA , 2 days ago
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RE: Renewables & Heat Pumps in the News
Critics and naysayers will be negative whatever the gov...
By JamesPa , 2 days ago
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RE: Microbore heat pump installs
In principle you are almost certainly right, but in pra...
By JamesPa , 2 days ago
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RE: Electricity price predictions
@old_scientist We are a low mileage home, so bulk of ou...
By ChandyKris , 2 days ago
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RE: What is the main ‘dictator’ of Agile’s unit price?
@toodles I keep an eye on wholesale prices and energy m...
By ChandyKris , 2 days ago
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RE: Upgrading my system, how far do I go?
For comparison, my PW3 with 11.04kW inverter, will char...
By Old_Scientist , 2 days ago
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RE: Changes to Tesla Powerwall Charging Regime?
Elon gate - legendary! I take my hat off to you @toodle...
By Old_Scientist , 3 days ago


