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Fentoozler
 
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Default Leaking Worcester Bosch Boiler

"Andrew Collins" com.hotmail@bflfcbb wrote in message
...
On Sat, 31 Dec 2005 22:33:51 GMT, wrote:

If the pressure is rising rapidly when heating, then it is likely that the
pressure vessel has lost charge. It's easy to check but the system needs
to
be cold and not pressurised. You will require a pressure guage (car type
is
adequate) and a foot pump or similar to re-charge. About 10psi (0.7bar) is
normal.


Heh... That's actually the *first* thing I did!

It does pressurize quickly, so the amount of pressure in the expansion
vessel could be wrong, but there was plenty of pressure in there when
I tested it. I will try to find out what the pressure should be for
the boiler and make sure it is correct.

It also leaks when the pressure is well under 2 bar (the maximum it
gets to), and I believe for this boiler the pressure relief valve
opens (or rather should open) at around 3 bar.

I *think* it is slightly better since I tweaked the valve yesterday. I
shall try it again later, but I suspect it needs replacing anyway.

Thanks,

Andrew

Pressure raising quickly is usually one of 4 things on a WB:

1. Blockage - unusual;
2. Pump stuck - unlikely if you're getting any CH and/or HW;
3. No pressure in expansion vessel - more likely;
4. Split in water-water heat exchanger - had this on later models (CDi
range), not on a 240 however.

The PRV requires replacing (again flushing it through (twist until it clicks
shut again)) - you can do this as often as you like until it stops leaking
or you get ****ed off. Remember to recharge when necessary.

If you do need to recharge the expansion vessel, use the guide above, but
remember to leave an open end when pumping it up (e.g. crank the PRV open
just before it clicks shut - it should stick open).

Angus