ProDave

The "issue" I have with this ASHP having the return as the set point, is it then maintains +5 for the flow temperature. I have observed with mine when only one UFH loop is on, there is very little difference between the flow and return, perhaps 2 degrees or even less. So I would never achieve the 5 degrees it wants and I would end up running with the flow temperature hotter than I want, by which time the return temperature would overshoot it's target. But it is the way the manufacturer has designed it so you have to work with it.

Without some serious re thinking on the wiring there is not much you can do about that. But it might be a handy measure of how much solar PV is going to the immersion heater if you are sure it is not the ASHP turning on the immersion.

Seriously. Get a scaffold tower on wheels for this job.

Yes it's positively "warm" here, only -14 last night and it got up to -4 this afternoon.

For the small extra cost get a dirty water model, if only for the fact they won't want it returned if there is an issue.

The end of my build should coincide with retiring, so time to go and do all the things / visit all the places on the bucket list. and I might get round to trying to make my classic Landrover look a bit nicer.

What do you call "very cold"? My 5kW LG ASHP has continied to heat my house and DHW when it was -14 last night and now at a daytime high of -4. No doubt the COP is not as good and it has needed to defrost a couple of times, but it has not stopped working.

I bought a cheap "dirty water pump" from Screwfix for pumping the water out of my foundation trenches. By the time it had finished doing that it was not pumping very well at all, and a quick look revealed the plastic impeller had just about disintegrated, unable to cope with pumping a few stones. A quick phone call to SF they refunded and did not want the old one back as it was "dirty water" So if you want it for short term use and don't care how long it lasts do the same. If you want it to last, make sure you get one with a metal impeller. I refurbished mine with parts of another pump with a failed motor that I was able to recover the impeller from,

As many of you will be aware I am the owner of an LG heat pump, and older model 5kW version. I had some teething problems that have been well documented on here and largely solved by myself. I found their technical support to be wanting. I am loathed to criticise them however as knowing mine is an old unit I would hope the issues I had have been corrected on more recent versions and seeing as you don't hear lots of complaints about the issues I had that is probably the case. We were down to -14 last night, and my LG ASHP has been working without issue keeping the house warm and heating the DHW. We have reached a daytime high of -4 just now. I would be surprised if many of you have a lower outside temperature than here (unless you live near Braemar which reached -22.9 last night, a record low for the UK this century) If you want to experience worse, feel for a friend who installed an good energy ASHP last year, and it stopped working last night with an error message that meant "ambient temperature too low" I have not heard yet how he has got on speaking to the manufacturer about that issue.

Is an area of the under floor still saturated and that is just conducting the heat away to the sub floor?

What is the specific issue? If you are installing mvhr you will need a gap to allow airflow between rooms.

Just resurecting this thread. Had a call from the guy this evening. His ASHP is tripping with an error code when when her looks it up in the manual means "Ambient temperature too low" He is not far from me and suffering very cold weather, only he says they have freezing fog where he is. He will be phoning the manufacturer tomorrow. I will be interested to find out what the issue is.

Nails used to be normal to nail plasterboard, screws are a modern innovation.

My view is it only makes sense if you can buy the kit cheaply and DIY install it. It cost me £1500 to buy and install a 4kW system, which I recon is saving me £250 per year in electricity costs so will have a 6 year payback time. Self usage is the key, I am not convinced battery storage is there yet, when you fully cost batteries including end of life replacement, your "free" electricity is not that cheap after all. The only payment now is the smart (sic) export payment scheme that will pay about 5p for anything exported, but to claim that you will need and MCS certified install which will probably add more to the cost than you will ever recoup in payments. Had I been eligible (I am not) in the first 2 years I would have been paid the grand sum of £12 for my export.

Keep your chin up. I think just about everyone has a wobble of some sort part way through a self build when not everything goes to plan. Take a break, then go back to it with a fresh mind. Plenty have come up against serious problems and beaten them. You will too.

@Jeremy Harris Heat loss calculator is in this thread

I tried a long run at 110M and it worked, just, very slow connection. No way will it work 200M without something in the middle.

A room sealed wood burning stove should not hurt an air test much.

Yes I believe that is so. That does not bode well. What is one supposed to do when you chose and installed a system in good faith knowing it had a BBA certificate only to find it no longer has. It is worryingly beginning to sound like "not fit for purpose" which opens a whole new can of worms.

The issue is one of trust. Even when "fixed" will i trust it not to happen again in 5 or 10 years? Yes gutted does not come close. this has been brewing up for a while and I have pushed it back relying on the plasterer saying he will sort it for a while as I could not do with the distraction while still busy building, but now is the time to face it and shout until I get a resolution.

Thanks, excellent link. A snippet from that That fits what I am experienceing but there is no way I can see there is any case of "dimensional changes" and no issue with incompatibility or poor weather during application. Yes the EWI is low to the ground just on that garage wall. If that was the only area of concern then I could believe that was the caiuse, but that would not explain why it is occuring above doors and windows and in other places where the EWI finishes much higher above the ground.

Something like this to monitor one appliance at a time https://www.ebay.co.uk/itm/UK-Plug-in-Electricity-Power-Consumption-Meter-Energy-Monitor-Watt-Kwh-Analyzer/333855058767?hash=item4dbb4feb4f:g:36kAAOSwL0Nf~Xn7 One day I will buy one and get to the bottom of our "other stuff" energy usage. Plug each appliance into it for a day or a week and see how much everything is using.

No it is the house we want rather than a budget house. Decent levels of insulation, Rationel triple glazed windows, Oak flooring doors, door frames and skirtings, and not cheap doors. Granite worktops, both bathrooms as wet rooms. But everything was priced and sourced carefully, e.g. Internorm windows would have been twice the price or Ratioel.

No that is the mesh embeded in the base coat. I don't think failure of the base coat is the root cause, rather because that section of top coat did not get repaired, water has soaked into the base coat in that region and frost has cracked it. I have not started to peel back any of the delaminated sections to look, I am awaiting communication from the supplier before I do that.

Except the designer of the house specified the system and provided the BBA certificate, I bought the materials, and a plasterer applied it. It was not a contract job to a "render company" The plasterer has offered to rework for free (though that will be tested if the whole lot has to come off) and I am awaiting a response from the supplier.