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Paul Barker

Quote:

Originally Posted by BigBird

"BigBird" wrote in message
...
I am thinking one (hopefully not both) of the above is the cause of my
problems. Symptoms being a fairly constant drip from the discharge pipe out
doors and steady drop in pressure in the system.

The boiler is an old Ferroli 77FF IIRC.

I am short on free time but need to get this sorted as am moving house.

I am hoping to confirm diagnosis. Gauge how much it will cost to have an
engineer fix this. Gauge whether it is a possible DIY job. I am competent
(IMHO) with general copperwork plumbing and as a general DIYist.

I will take a closer look at the valve shortly and am giving over tomorrow
to get this fixed if possible and necessary whether calling engineers or
DIY.

Comments please.
Well thinking about it obviously the valve must be faulty to release water
at such low pressures. Anyway as can be expected testing the valve has
exacerbated the fault. Now more than a steady drip.

I have a spare on standby now and inhibitor too. It is just a matter of
whether there is something which prevents it being a DIY job and whether the
expansion chamber is also faulty. I'm still thinking it possible a faulty
chamber may have came before a faulty valve.

You're thinking on the right lines.

Sometimes you can clear the seat of the prv by geting th ehating roasting hot switching off the boiler and manually blowing a good jet out of the prv. If this fails you do have to change it.

As a secondary issue check the expansion vessel. If it is working correctly the pressure in the system should rise about 1/2 a bar from cold to hot, this depends on the size of your system. If it only rises to around 1/2 a bar greater, then no need to investigate further.

If it is faulty, let all the air out (if there is any) of the Shrieder valve (bike pump valve). If water comes out you need a new vessel. If air or no air but no water either, drain your system until there is 1/2 a bar showing on your built in guage. Get your bike pump and manually pump up the vessel a further 1/2 to 1 bar i.e. watch the guage go up by that amount. (whatever pressure your manufacturers instructions advise, 0.75 bar if no advice.).