ProDave

Did the tree come down in a storm? If so insurance claim, then the cost does not bother you?

I would only add, remove your post and wire fence to make it easier to maintain the sloping bank, but keep the big end posts in place as markers and the photos just so you have a record of where the fence used to be.

Wise words. At the moment, even with the higher prices, even with a perfect ASHP system in a good house, the savings over gas would be small, so the payback time would be huge. If I had a working gas system I would not be changing at least not changing with the expectation of saving money. I wonder what claims the supplier made (the supplier that has now gone bust so won't have to honour any claims)

Can you post pictures of everything you have including close up pictures of labels, model numbers etc.

Not in todays high energy prices, especially if that is £200 per month for 6 months only, i.e. winter.

It is unlikely the heat pump is actually using that. They normally have a temperature probe in a pocket giving a much more accurate measure of tank temperature and allowing you to set the tank temperature from the control panel. The traditional tank thermostat is just there as a required G3 safety device, to close the motorised valve and shut off the heat source in the event of a malfunction. My own is there for just that eventuality and is set to 60 degrees. To move this discussion forwards we really need historic gas usage, preferably from actual monthly meter readings not estimates, and the predicted heat loss calculations provided by the installer.

1.4 metres between fences (boundary dispute as you can't agree on one fence line?) and 1.5 metres height difference. So if that is just a sloping bank it is pretty much 45 degrees and perfectly stable. So unless you want to move your fence to widen the flat area of land between your garage and the new fence / wall, I don't see much need to do anything? Perhaps some low maintenance shrub planting?

That looks like a big heat pump so presumably an old house not much insulation? Did they do any heat loss calculations before quoting? All thermometers are low so presumably turned off when you took the photographs? What are we supposed to be looking at in the last picture? The general install looks reasonable, some more pipe insulation would be a good idea but I doubt that on it's own would account for the high bills. How much were you previously paying for gas? That is the best indicator what your running costs might be.

If the MCB tripped earlier and a switch welded, that is a short circuit somewhere. Most likely explanation is a pinched cable in the back box of the switch you have just replaced, and in the act of replacing the switch it is no longer pinched and causing a short circuit. Prime candidates are too tight behind the switch in a shallow back box, or one of the fixing screws pinching a cable.

I am pretty sure the LG puts up a little symbol on it's control panel when the resistance heater comes on.

Yes there are less choices of switch type for intermediate, and it is hard to get an intermediate in a 2 or 3 gang switch.

Yes automatic changeover 2 cylinder setup. If the property still has a gas hob then make sure the vendor includes the gas bottles or you will be going and hiring a new pair. If no longer any gas appliences (e.g all electric now) and you don't intend having a gas hob it can be removed.

I would put my money on either the upstairs switch has failed, or one cable has come loose as the first place to look. If not there, the next switch in the chain which will be an intermediate switch, that may or may not be the one at the bottom of the stairs.

the Therma V does not switch itself off when it gets cold, it may switch on the resistance heater as well. That is very configurable. I have mine disabled so it is never used, but my HP is well within the total heating power requirement.

It's on a par with the toilet cisterns refilling with 4C water and just sitting there being warmed up by heat from the house.

My LG simply turns on the water pump periodically to keep the water outside above an undocumented lower limit. In fact there is really nothing documented about this (very poor) and I have not found any settings to adjust anything about this function. So it WILL expect water to flow when it wants it, from somewhere. It won't run a defrost cycle as the compressor and heat pump is not running. Rather than re invent the wheel, why not let e.g the LG heat pump turn on it's own internal 3kW electric heater if the heat pump is unable to maintain the set flow temperature demanded? It won't be the heat pump unable to function because it is too cold, the problem you might face is it can't get the flow temperature high enough if heating demand exceeds the heat it can provide.

Modern stoves have a limit on how far you can shut down the intake to meet modern limits. Some have a little crafty footnote that you can remove the stop if you really really want to close it down further.

Urban myth I think. I have just checked with the Ir thermometer, and no part of the stove or the single wall flue exiting the top, is any colder than any other part of the room, so any natural draught and heat loss through the stove is tiny. My intake duct is insulated as it passes through the wall then down under the floor. It does not get hot there, I used plastic ducting once it enters the wall and down.

Buy yourself a couple of these this one just as an example from https://www.ebay.co.uk/itm/275552493434?hash=item4028355f7a:g:g0AAAOSwbqRjfNZ7&amdata=enc%3AAQAHAAAAoDzqDZhBEFGC%2FD7CD3ceaM5Ahx%2F%2BVHlp%2F5jPJkZnKkIUMZ7t5wIkfNvL3IweWYNoCcy%2BsB2Jg%2BwnORTSXZT16neUElao%2FZH%2BUNiHO1hoCpI9JDsb3dzZYWLLM%2BF2Kv2sSzLF6LK8tn48TzWiDEApveIUqsnEawlfWhNFz8bidI1s8pC9kodv3v0ZTMHprJO%2FNSd03mKB9SQ9CILmQMYef0E%3D|tkp%3ABk9SR8CZyPbJYQ They have provision for fitting a water meter which you probably don't want so make sure they come with the blanking plug to go in when no meter is fitted.

With a lot of the self builds on here, by the time you have finished, most of the stuff you fitted at the start is out of warranty.

I would not pour the screed yet. While you have improved the cold feed situation, you still have the cold feed to other parts of the house buried in that same screed.

A fine tooth panel saw is easier to get a straight cut.

With a saw. What other options are you expecting?

Yes I believe the way forward is to halt the job, meet with your BC inspector yourself without the builder present to intimidate you, go round all the points this thread has highlighted with him and get him to evaluate them, and then provide you with a list of things that need correcting before the job progresses. Your builder won't be able to argue with that.

Only bought the business in 2023. Lack of due diligence, Or deliberate asset stripping exercise?