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Last seen: Jun 26, 2026
I thought I would share this DIY split system air to air a/c install. This is an R290 propane unit sold by Appliances Direct after the buyer said he w...
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 ...
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Degrees of Separation
Latest Posts
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RE: Do I add Air Con or MVHR to existing A2W ASHP?
@toodles I would recommend an A2A system. We have Dai...
By Rob of York , 13 minutes ago
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@rob-of-york welcome to the forums. Solid numbers. A...
By Mars , 25 minutes ago
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RE: Questions about A2A for heating as well as cooling
@donciccio I would suggest that you take a "fabric-fi...
By Rob of York , 38 minutes ago
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RE: How Accurate Is My DIY Heat Loss Calculation?
Any idea how efficient your gas boiler is? Is it a 50 y...
By Old_Scientist , 5 hours ago
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RE: Volumisers in Heat Pump Systems: Does Placement Matter?
@dave, I think @jamespa has probably identified the mos...
By Mars , 17 hours ago
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RE: Plug and play solar. Thoughts?
My thought is simple. Bring it on and bring on plug in...
By JamesPa , 1 day ago
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RE: Heat Geek mini store vs pump size
Yes I agree, that’s why Heat Geek have most likely sele...
By Tomtheheatingengineer , 2 days ago
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RE: Who's your electricity provider and what's your tariff?
@chandykris Swings and Roundabouts, you win some…. ...
By Toodles , 2 days ago
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@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 2 days ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 2 days ago
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RE: Is the "divide by 2900" rule still valid?
Really flow rate is a pipework limitation not a water p...
By JamesPa , 3 days ago
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RE: The good, the bad and the not that great – my heat pump installation
@burtis, I’ve followed this thread pretty much from the...
By Mars , 6 days ago
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RE: Starting Our Heat Pump Journey: 1962 build 3 bed detached house
First time poster here but I can share my experience as...
By SCH , 6 days ago
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