Yes, I think it’s classed as 20mm, but not 100%. The branch coming off to your stopcock should be 1/2” thread though.
Yes should unscrew, and yes ptfe on threaded joint or paste. Could buy an adapter to join outlet end.
Yes, but make sure there’s no damaged wiring :p:p:p
Your 1st solution: might not have enough room. 2nd solution may work (adjustable bend) or possibly one of these?...
If it’s only the gland nut leaking, then can you not just repair it? Or worst case, renew the innards of stopcock? Steel will probably be 1/2”...
Looks a bit like steel. Come off stopcock in copper, as for changing it, either pipe freeze kit, or turn off the other one.
Your pipe that came with the frame, should have fins on for the floor. Are you able to move the frame?
There should be another stopcock down below, or externally (which may do several flats). It would probably be best done in copper, but bore looks...
Couple of offsets or extend into membrane.
Doesn’t look like asbestos imo.
You could lower it, or when nearer to, remove it and flush with a bucket.
I wondered what fixitflav was referring to as a phial. I might need an eye test ;)
I don’t think the heat exchanger being blocked would stop it coming out at 45 degrees. More likely that your temperature control on the cylinder...
If severely blocked, no chemical or flush will get rid of it.
“Taps” are gate valves for isolation purposes, but can be prone to snapping if used incorrectly, or wear/tear.
Just need someone like this to disconnect harnesses up top, and it could be game over:
As @ianmcd asks, why are you asking about not heating hot water 1st? It sounds like a combi boiler, so heat on demand.
If you do indeed have a combi boiler, then check valves are not normally required.
Probably, seen a few of “ours” like this.
Op - carful of the panel, could contain asbestos. McAlpine couplings would also work.
So could be locking out with the valve being positioned the wrong direction of flow then?
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