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Last seen: Jan 7, 2026
My original “design" from my installer for my 11.2KW heat pump was a 9 zone system. One of the zones had a flow rate of under a litre a minute. That...
@gergoh The 8kw newish r290 Mitshi machine can modulate really low. might be a good option.
@ashp-bobba I'm not a heating engineer, but with a heat loss of 2.5kw at minus whatever, is there any heat pump that can modulated low enough ...
@cbrenewable What's the heat output each day for the last few days, and the input. My COP is 6 and over at the minute. The big rads not gettin...
@cbrenewable Hi, the graphs from Mel pump would be good. Can you draw your system, have you got a low loss header? or are you directly piped into ...
@sandman1600 you need to measure whats going on really before you make loads of changes. If you can measure the temp of the flow and return to and ...
the reason why cop is bad is the delta t's on the primary circuit are small, so its not giving out much energy by the mitshi calculations. nobody kno...
Has anyone been to check what is going on with the secondary side of the system with the UFH? I’ve not read all the posts recently. The minimum modula...
Yeah, big balance isn’t it. Big enough to heat commonly cold days, but not so big ruins more typical temps. im not sure where in the country the unit ...
I’ve circle your compressor output. It’s just going from low to minimum output to off. And then as we thought, off all day. But it’s warm today, but m...
@sandman1600 it’s tricky. Looking at the graphs: it’s not ideal. It’s on/ off all the time as it can’t modulate lower. Personally, I’d not be hap...
@gary mine was “designed” to 45, bit system can’t get above 36. That bit was nonsense. from looking at your graphs of one day: you’ve got loads of ...
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Latest Posts
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RE: Volumisers in Heat Pump Systems: Does Placement Matter?
Volumisers are normally plumbed so that they are in the...
By JamesPa , 4 hours ago
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@toodles possibly. The £9k labour charge for 4-5 days w...
By AndrewJ , 8 hours ago
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RE: Plug and play solar. Thoughts?
My thought is simple. Bring it on and bring on plug in...
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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 , 1 day 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 , 1 day ago
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@tomtheheatingengineer, thank you, and welcome to the f...
By Mars , 1 day ago
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RE: HeatGeek vs Octopus surveys: puzzling disparity - any ideas why?
@majordennisbloodnok @tomtheheatingengineer For my ...
By JamesPa , 1 day ago
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RE: Do I add Air Con or MVHR to existing A2W ASHP?
There is scope for product development here. I for one...
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 , 2 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...
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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...
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RE: Is it the house or the equipment?
...which, I've found out, is pretty much impossible to ...
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