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Last seen: Oct 20, 2026
@jamespa Hello James. I am a little "under the weather" literally and metaphorically, so delayed response. 1 - The approximately 2m of 25mm pipework...
@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 ...
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Latest Posts
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RE: How will removing the standing charge on gas bills benefit heat pumps?
I'm not sure it makes much of a difference to heat-pump...
By Temperature_Gradient , 6 hours ago
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@editor Ouch, sorry to re start the tick. I had assume...
By DavidB , 6 hours ago
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RE: Say hello and introduce yourself
@e-a-west as the good Major said, welcome to the forums...
By Mars , 8 hours ago
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RE: New Build 3 Phase or 1Phase
We are on three phase power because it's an enormous li...
By EtchedPixels , 8 hours ago
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RE: How much of your renewable and home setup would still work if the internet went down?
Yes I actually have a copy of a tool that whenever a ce...
By EtchedPixels , 17 hours ago
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RE: Indevolt Batteries UK Support & Info Thread
@editor Hi, To resolve this, please tap on the A...
By Indevolt Tech , 1 day ago
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RE: Double or Triple Glazed Windows?
Posted by: @singlespeed With 9 years repairing windo...
By Rob of York , 2 days ago
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@transparent we’re still running a secure version of PH...
By Mars , 2 days ago
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RE: How quickly would you want/expect heat recovery to take from setback?
Much longer than that here. The heating isn't even on. ...
By bobflux , 2 days ago
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RE: Passiv Smart Thermostat - Help & Forum Support
Obviously the weather is changeable but there's a defin...
By Singlespeed , 2 days ago
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RE: The Changing Jet Stream Could Challenge UK Air Source Heat Pumps
@rob-of-york I must admit that when we had a Daikin hea...
By Toodles , 2 days ago
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RE: Forum updates, announcements & issues
Get the Renewable Heating Hub heads-up on WhatsApp. I...
By Mars , 3 days ago
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RE: Safety study for plug in batteries out to tender - looks like Q3 2027 at best before legal
@editor I pointed out to the one of the Fuse execs that...
By dansus , 3 days ago
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RE: 15kw pump for 225m2 1990's house - over kill?
@seaviews As well as loft insulation, there are othe...
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