ProDave

Do let us know what they say. I am a big fan of ASHP's used correctly but deeply sceptical about the plans to replace most gas boilers with an ASHP as I fear the vast majority are going to end up like this performing badly, and the resulting bad press will have everyone claiming ASHP's are rubbish.

Refreshing to hear. Ours too is working well. It shows that properly designed they do perform well and in cold weather. Sadly the forum is seeing a lot of threads about ASHP's behaving badly in the current weather.

The screws won't make the VCL like a sieve as the screw will remain filling the hole. If a screw does miss the joist, leave it in place, don't pull it out, and fit another one and try again, making the appropriate adjustment in your aim.

A 3 port 2 position changeover valve is okay, they feed one or the other, never both. It is the 3 port mid position valve that by some trickery / bodgery can be made to stop half way and feed both together that I think is the work of the devil.

Go back to the company and say their advice was wrong. Was this funded by any sort of grant? If they won't admit they got it wrong, try trading standards. The ambition go go green is good, it is just a shame you have so far had bad advice from an installer.

Millions of people will learn this lesson the hard way, if the government gets their way and people do start en-mass swapping gas boilers for ASHP's with nothing else being done.

How is yours plumbed to switch between hot water and heating? two 2 port valves ore one 3 port valve? Try turning the hot water back on again and see if the fault comes back? I am not seeing anything in that photo that looks like a heat exchanger to me (does not mean it is not)

No that is not going to work like that. Contact LG directly. Don't say anything about install not finished, just say it is a new system just being started for the first time now, and it clearly is not defrosting as it should. Your supplier should also take the same view, shame you mentioned to him that the install was not finished as typical today everyone is looking for an easy get out clause to not address the problem. This is not something you can turn on or off or do manually so if it is not working it must be a fault. With it turned off you could try defrosting with warm water but unless the air temperature is now above zero, the water left on the evaporator will just freeze again.

It sounds like your ASHP installer has badly misled you. Perversely at the moment, it seems oil has gone up in price in the present cost of living crises less than gas and electricity has. But if you have been "sold" an ashp that only works properly if the radiators are ran at over 50 degrees, then that is a poor install. Unlike other heat sources ASHP's work best with low temperature water, so that usually means under floor heating or larger low temperature radiators. Even with everything just right, an ASHP will just about match the cost of for instance mains gas. They are not a magic cheaper form of heating, anyone telling you that is somewhere between optimistic and fraudulent. they do have environmental benefits, less CO2 emissions.

Can you post a picture? Do you have an IR thermometer so you can do a non contact temperature reading of a hard to reach part?

More details please, house type, age, insulation levels, and what heating was there befoer. Cheaper than what? Don't forget temperatures now are probably colder than you have had for a very long time, especially down south.

Which is why we should be investing in tidal power, that is absolutely predictable (all but minor differences due to air pressure)

So find the heat exchange in the outside unit. It will have 2 thin refrigerant pipes probably soldered, and 2 larger water pipes. If the refrigerant pipes are hot, and possibly both the same temperature, but the water pipes are cold, this suggests little or no flow through the water pipes to take the heat away. In normal operation you would expect one refrigerant pipe to be hot and the other to be less hot as the water will have removed some heat as it passes through the heat exchanger, and you would expect the water pipes to be warm. I had lots of low flow issues with mine when I first ran it and the best thing I did was bought a flow meter and connected that in line with the pipes to the outside unit so I could see what flow I was getting.

Hot pipe out of the compressor usually means the water is not removing the heat from the heat exchanger fast enough. I would look at your plumbing to ensure water is really flowing to the outside unit. It could be the pump is running but no flow due to ice or an air lock for example? Is the pressure high enough?

Planning does not usually set a time limit for completion. So it would still be a "work in progress" If the garage requires building regs approval then you would have to pay separately for that if you build it later. Could you at least put in the foundations and pour the slab, then it is an easy job to build later when you can.

Except the silly way we do things it would not surprise me if we mandated it has to be a type approved charger installed by some member of a special club who has been on the right course and will cost you ££££

Or just changing it for the non spyware version after completion sign off? Just more hops for a builder to jump through.

I think the high cost is the weather, not a "fault" If the UFH is failing to deliver enough heat to the rooms, then it will use less gas. If it is burning a lot of gas the heat has to be going somewhere. Don't confuse the higher cost of gas per unit with thinking it is burning more gas.

I was put off an EAHP by several reports on a previous forum before buildhub started, of a lot of failures of what at the time seemed to be the most popular make of EAHP. I have not seen such reports for a while so I assume any issues were solved.

The reason most of the time JET used Tritium was it was fairly harmless. During shutdowns between operation, people could enter the Torus hall to carry out maintenance and upgrades. Once Tritium was used, the machine is now highly radioactive so all work is now carried out with some quite complex robotics. It was always the plan that the tritium phase would be left to the very end, and it is only because it has operated for far longer than originally planned that the tritium phase got delayed. The building was only given 25 years temporary planning permission at the start, and the standing joke was it would eventually become the third Wittenham Clump.

I am pretty sure the 24V is used for all the I/O there are certainly 24V relays in the box it connects to. The daughter board is probably the microcontroller, mostly enclosed in a metal can, and what you can see is a lot of chips with an awful lot of pins. I might have to uncouple that board, it would make replacing some of the capacitors easier, but it is soldered to the main board with a "link" in one corner. I am nervous of unsoldering that, I think it may have been put there specifically to stop you unplugging it. My fear would be the CR2032 battery is on the main board, and uncoupling that could lose it's backup and you might promptly clear it's memory. Not worth the risk without knowing for sure.

This board is not exactly cutting edge stuff, there is a lot of 74HCT logic so we can assume the main output voltage will be 5V There may be other outputs I have not tried tracing the circuit yet. As far as I can tell only a 2 layer board so that should be possible no hidden tracks or blind vias. If I get no luck with fixing the on board PSU then powering it from an off board PSU is plan B The unit is made by Carel. If you buy one direct it will not be programmed. It is Dimplex that will sell you one pre programmed for the heat pump. But the parameters won't be set up. If we can get this one working we are hoping it's program and parameters are intact, but of course a failing PSU could have damaged other stuff on the board. The shopping list for parts so far is only about £10 so worth a try.

Both 1000uF 50V. There are two 470uF 50V on their side under that sub panel, and a 220uF 25V in an even harder to reach place. This unit is fed with 24V ac from a transformer and derives it's internal dc voltages from that via this blown PSU section.

If you want some context, I am trying to rebuild the power supply part of the controller in the industrial sized GSHP at our village hall. The tally of failed components found so far, 5 failed capacitors, 2 failed tab power transistors and this diode. the failed diode is just below the left hand blue capacitor in this photo The scorched pcb area just below the transistor with a heatsink (one of the failed ones) is not as bad as it looks. Those 2 smd resistors are all in fact okay, the scorching is the pcb track underneath them did the job of a fuse when the PSU failed. I don't rate the chance of it just working when I fit the new components as very high, but I said I would give it a go. If I can't fix it, it;s £1400 for a new controller. No pressure there then. And of course I can't find any service information.

Not de soldered it, but referring to the data sheet linked above, pins 1 and 3 are shorted, so that is clearly one diode short. The photo is not the failed part, i could not get the lighting right to photograph it, it is a photo of an identical part in a different part of the board that was easier to get to. the failed one has a corner blown off, which is what alerted me to it on a visual inspection.