ProDave

Okay so your treatment plant is drawing 300w continuously. Is this an actual treatment plant? or just a pumping station? Turn it back on and go and have a look. Is the pump stuck on? could the float switch be stuck or faulty?

It seems to hinge on whether or not the boat was on a residential mooring or not.

You might want to turn off the PV while doing these tests or that will confuse a lot of those simple energy monitors. Just turn off the big AC isolator that should be close to the PV inverter.

Something like this would help https://www.ebay.co.uk/itm/352603604716?epid=11023571779&hash=item5218d006ec:g:8j0AAOSwQJ1edcDA It would clamp onto one of your meter tails and give you a real time read out of current being used and make finding it a lot easier. That one is from China. your task now is to find something not too expensive that is posted from the UK. Or wait 3 weeks for it.

What are the figures in the fight hand column? Is that how many kWh you have used in each half hour period? Of so that's about 0.5kWh in each half hour so about 1kWh in each hour. In other words you are looking for a rogue 1kW load The blunt way to tell is switch off the circuits at the consumer unit one at a time and measure for the next hour until you find the one where the load drops when turned off. That will give a clue.

If you are looking for a "heat pump specialist" I suspect those will only work on the systems they know and have done the manufacturers courses for. Look instead for a good plumber and a good electrician. The "good" bit meaning they are willing to do something a little outside their normal scope and above all are prepared to read the manual and follow it. Any plumber and electrician that can read and apply what it says in the manual should be able to do this. I fitted ours as my first ever heat pump and have since wired another on a new build. It is not difficult.

Yes it would have to be a syphonic flush to achieve what you want. What is the issue though? Surely the tenant pays the water bill so leaking flush = higher bill for them?

2M will. I thought building regs demanded 2M over stairs and a landing without actually specifying a minimum anywhere else? But stairs up from a garage, only roof windows in a 2M ceiling (too high for means of escape) are the starters for why this would not pass BR.

That looks like the previous owners butchered flexi pipe. As above, at the stove end, you should find a bayonet fitting. Start from there with a new hose set.

The move to net zero won't be achieved simply by swapping gas boilers for heat pumps, and then all the extra electricity needed to power all these heat pumps being provided by gas fired power plants. It is just one part of the solution, and it relies on an increase in carbon neutral electricity production.

This looks to me like a failure of the flooring, the top, Oak layer has warped and separated from the structural layers. I bet the manufacturer will blame you or the installer, excessive moisture, not enough moisture, to hot etc etc etc rather than admit a failure like that could happen. Ours has been down 3 years, no problems like that, UFH on, and the floor even gets carefully mopped once in a while. One question though, that has occurred at a change of direction. Are ALL the faults at a change of direction, i.e. where very likely the boards do not interlock with a tongue and groove?

South elevation finished, apart from making a permanent "platform" in front of the cat flap and some steps down for the cat......

Carpet in the entrance then. Any form of tiles or planked floor will show up the fact the wall is not square. Knock it down and rebuild. 100m out? 50mm overhang from foundation each end? Does it have to be block? Is is supporting anything? how about replace with a stud wall?

I almost never give quotes. If I had to quote a fixed price for every job, I would have to take account of every difficulty that I might encounter and factor in the job taking that long, and the quote would be higher and I probably would not get the job. Usually I estimate jobs and most times things go well and the final bill is lower or no higher than the estimate.

You don't want to open a centre pivot wide anyway or else it will get wet inside when it rains. I would be more concerned with BC getting upset if headroom above a stair was less than 2M with the window open.

These old leaky houses "worked" as long as you throw a lot of heat into them. Fine when it is cheap and the consequences (MMGW) don't matter. But now we know with a properly built house you CAN walk around all year in your tee shirt without needing a lot of energy input to keep it that way. The "solution" is known. It's how we get from the old housing stock we have to that, that is not yet known.

It's probably a clay pipe they have broken then and don't know how to fix it?

When their garden starts to fill with your sewage, I am sure they will think about fixing it.

This is getting off topic, but the issues I see with older houses are as above. We used to live in a 1930's semi that leaked heat like it was going out of fashion. We built an extension in the 1990's that was a bit better but not a lot. That was heated with an LPG boiler with an eye watering appetite for gas. But I didn't know any better. I grew up in a similar 1930's semi that sometimes in winter could not even maintain a comfortable temperature in spite of the radiators being piping hot, and just accepted bedrooms were cold places especially at night when the heating went off and they quickly cooled down. I suspect there are still a LOT of people accepting this level of heating as "normal" and think nothing of it. Yes in theory you could heat that house with an ASHP, but it would have to deliver as much heat into the house as the gas boiler did, and would as a minimum need larger radiators to operate at a lower temperature. As has been mentioned it would never match gas prices, a well designed system might get close but would never match it. So you would need much larger radiators, a very large heat pump, possibly an upgrade to a 3 phase supply to power it? and the "benefit" for all your efforts and capital outlay would still be higher bills. So I would certainly not be advising an ASHP for that type of house. The elephant in the room, and a problem that must be solved is just what are we going to do to all the houses like this to make them more energy efficient, and who is going to pay for it? What is really needed is a strip back to bare shell, insulate everything and seal it for decent air tightness and then while doing that level of refurb fit UFH and then it might be a candidate for a sensible size heat pump. There was a bit on the STV news recently about them doing exactly that to a Glasgow tenement block as a test bed to see exactly what is required to bring the building up to a modern standard. The brief shots they showed appeared to show wood fibre or similar insulation slabs being used to line all the external walls on the inside.

Just apply to your water company for a permanent supply to the plot. Obviously you will install a standpipe for use just now.

A waterless trap and the pipework should be ABS, not PVC, to withstand the potentially boiling water discharging from the UVC

Like others here, mains gas was simply not an option here, it is at least 3 miles to the nearest gas main. But even if mains gas were available, there is the standing charge to consider. A quick search suggests that is typically £90 per year. So if I had installed mains gas just to heat my home, then the gas usage bill would have to be less than £160 per year for gas to be "cheaper" than my heat pump.

That is not a new document. I did my own percolation tests, and nobody queried it. Officially HC seem to be pushing the "approved certifier" route but in practice are not bothering to enforce it. I have not used a single approved certifier contractor.

In a well insulated air tight house, there is no risk of condensation because that needs a cold surface to condense onto, and there will be no cold surfaces. Trust me, in a well insulated air tight house with mvhr, condensation is simply something that does not happen.

@Dave Jones Rather than keep on telling everybody how rubbish heat pumps are, I would really like you to start a new thread outlining exactly what problems you had in the past with a heat pump. Then perhaps we can begin to understand what actually went wrong, and everybody, including yourself, could learn why your system did not work, and what could have been done to make it work and what can be done to make other retro fit systems work.