dpmiller

for fine temperature control. This is in steam sterilisers, we're switching heating loads of up to 50kW and a failed-short would be seriously bad. But control has to be good enough to not overshoot too... So we have one contactor as a safety device on an independent control, and then actual heater switching is carried out by SSRs or another contactor, depending on brand/model

in the kit I work with, a SSR generally has a series contactor for failsafe isolation

yes, but that's all it is. An opinion.

what woodburner is it that needs a 250mm flue?

remember that with an ASHP you're working with less differential between coil and tank contents which pushes the requirement for a bigger transfer area

my WH cylinder has coils which are 3m2 and 42kW...

what's the spec of the coil? ASHP ones do tend to be bigger I'd be surprised if WB aren't adding a premium to the price too...

as will World Heat.

pass a heat gun or blowtorch over it?

Umm, which country are we in?

how much gas remains in the tank?

I've gone with Klik sockets rather than 5A although I believe they're now discontinued in the 1-gang format. Gives the option of switched or permanent live (or a second switched service if necessary) and they're nice and finger-safe too. Klik ceiling roses too.

It's inverter. One very quick look at the schematic shows the compressor as having three connections WUV. Means 3-phase...

Sitrep. Cooker *did* arrive, operation festive food was a success. Still waiting for the shed More tiling done. Now... interesting stat time. Current abode is about 700sqft and not incredibly hard to heat in my experience. I put 500l of oil in the tank at the start of December and looking at the tank I'll be ordering oil again next week. While the previous purchase was about £260 it'll now be about £320 for the same quantity In comparison, I got the quarterly electric bill for the new place last week- £340, or 1860kWh. For 2700sqft...

where in the world are you?

so it's a spur off a spur? Where is this one powered from then? No earth sleeving where you come from?

can a gennie- specifically the more efficient inverter ones- clamp the output of the solar inverters sufficiently to stop overvoltage trip outs?

@Dan F I was referring to the ASHP pump.

I'm kinda surprised that @Dan F's unit doesn't have a variable-speed pump, are the big-name ASHPs not generally equipped with this? Our Cool Energy does, and it's well used as part of the modulation strategy.

Chinesium hot water tap is tankless, but how about just putting a drain-down valve on the supply so you can isolate and drain down the line between occasional uses in cold weather?

@ProDave sorry if I missed it but have you tried the head office in Austria?

@ProDave here's some blurb from Honeywell- https://youlearn.honeywellhome.com/uploads/documents/FAQ_-_Optimisation.pdf

It's like the "optimum start" feature on some older digital roomstats- they learn the rate-of-change of the room/house and re-start from the setback temp in time to have regained temperature at a selected time. The lower the internal temp falls overnight, the earlier the heat comes on. but as @Marvin alludes, how much of a point there is to this in a well-insulated property with an ASHP, is questionable

@vala no, the boiler stat is a final protective really, the buffer controls should be doing the work. If the house is being heated well in all situations you might consider having a smaller jet fitted to the boiler to reduce it's capacity a bit?

turn it up a bit.