I have a traditional vented and fully pumped system. I also
have a water softener in the kitchen which sprang a leak from
somewhere inaccessible at the back. So I closed the flow and
return valves and opened the bypass valve to stop the leak until such
time as I could properly get to it.
Except - I didn't check that the bypass valve was really open. It
wasn't until I got home from work 24 hours later and SWMBO informed
me that we had no water from some of the taps that I realised. The
bypass valve was stiff and I had just turned the lever, not the valve.
By the time I had opened it properly the damage was done. I guess both
the cold water storage tank and the hot water cylinder had drained.
And the shower pump had run dry.
Now we have virtually no hot water (and I think the hot side of the
shower pump is shagged).
It has symptoms of an airlock but I can't get it out after days of
trying so I think that's not it. I think what has really happened is
there is a blockage in the cold feed to the cylinder causing very low
flow. At equilibrium the vent pipe is nearly full, so when you open a
hot tap you get the contents of the vent pipe then nothing. The shower
runs cold unless you turn the mixer to full hot, then it's feeble.
I can live with replacing the shower pump, all the connections are
pushfit, but how on earth do I fix the blockage (if that is what it
is)? The feed to the cylinder is right at the back of the airing
cupboard, a pig to get to, and the drain cock is only 1" above the
I have had it suggested that the blockage may be at the top of the
cylinder, in the outlet pipe - but that's equally a challenge. The
pipe runs horizontally from the coupling at the top of the cylinder to
a tee which is only 1/4" away from the wall - I don't think that
amount of movement will release the pipe from the coupling, I'll have
to move the whole cylinder the other way. I'm really reluctant to do
that what with all the other pipework.
Any ideas how I can confirm if it is a blockage and if so where it is
likely to be? And where does one buy rubber tube these days, if I need
to drain the cylinder I'll probably have to run a tube out of the
window and rely on siphoning to empty it, since the bottom of the
window is about 3' higher than the drain cock.
I hate plumbing....I think I'll go for electric underfloor heating in
my next house and hang the running costs...
- posted 12 years ago