Progress! The householder has sent me a video of water gushing out of the input valve - here is a still:
So it looks like the problem is with that input valve (see previous post for probable identification of the part). It looks rather like the problem I used to get with old fashioned...
Reopening this thread because I think I have identified one of parts of this flush system which may give a clue what comprises the rest of the mechanism:
https://www.bathroomspareparts.co.uk/uni-top-flush-air-gap-side-entry-fill-valve-a28-06-31-192610-p.asp
My non-plumber instincts tell me the...
Bringing this thread back because I have got back to the house and taken some pics:
Can someone tell me what I am looking at as I am not even sure how many components there are. Is that flat-topped white structure with the yellow cable a part of the flush mechanism or something else (in which...
You can see a small (4mm) gap on each side of that vertical panel. Maybe I should try inserting something thin and bent on each side and tugging. As for the strange arrangement, I have to tell you this would-be plumber has not attached either the bath or the kitchen taps to the bath and sink...
My son recently bought a house, the previous owner of which did extensive renovations of the plumbing, including enclosing the WC in a Fort Knox of plywood. Water has started intermittently leaking into the pan. I have fixed a similar problem on my own WC (replaced the siamp valve) but mine has...
Thanks again Madrab. So 'venting' covers both water and trapped air. I presume the water to the hot taps is also not actually pumped. Just one more uncertainty. There is a pump in the airing cupboard ('Flomasta'). Will this be the only pump in the system, or will there be another one in the...
Thanks Madrab, this is all starting to make sense. I'm going to guess there is a head of water in that vent pipe (as per MeldrewMate's post) and the weight of that column of hot water balances the upward force put on the water by the pump, so that hot water doesn't normally flow into the cold...
Thanks MeldrewsMate, that makes perfect sense and takes me back to physics classes at school many decades ago. Considering the various dodgy jobs that have been perpetrated on my house plumbing I would not be surprised to find sinusoidal or even helical piping somewhere. I think I have...
Thanks Madrab and Fixitflav. The plumbing is indeed less than optimum. The problems started when a builder friend who did plumbing (note: not a plumber friend who did building) did a major job (I can't remember what it was) after which the central heating wasn't working properly. I called in a...
Thanks Fixitflav, you don't meet many physicists on this forum!
I haven't thought of inverted U traps; that could be the answer. Unfortunately my plumbing knowledge is at the same level as my knowledge of embroidery. I don't know anything about vents, but I will attach two old pictures from...
Not a DIY question but this is something I want to understand before I die.
I have a gravity shower fed from the hot water cylinder and the cold water tank. Every other time I turn on the shower the water is only flowing about half as fast as it ought to. Usually I can fix this by holding the...