In article ,
"AL_n" writes:
"AL_n" wrote in
:

The header tank atop my immersion heater has a brass float-operated
valve. It started leaking last year, allowing water to leak out of the


PS... My valve happens to have the 3/4" threads, making it one of the more
expensive ones (as compared to 1/2" ones which can be got for as little as
£5 or so....

I would have thought a plumbers merchant would have the rubber,
although possibly only an older independant one. If you said
where you are, someone might point you to a suitable one.
Also look at the valve seat (which the rubber presses against),
as a leak can result in the water cutting a channel in it.

I think that nowadays this type is used mainly for central heating
header tanks, i.e. low usage. The mechanism used in stored water
header tanks and toilet cisterns is the fast shut-off type, which
uses the water pressure to shut off rather than the force on the
float to shut off.

Any idea why your tank has a large one? Is it a low pressure feed
from another tank not much higher up?

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]