Glow worm 30cxi pressure problem

[toprod]

Hi there,
Please can any body shed some light on this problem ..... I fill the boiler to 1.2 bar and increase thermostat and the boiler fires up and pressure increses to around 1.4 bar works for several hours then when it switches off on timer and when you awake there is no pressure it's dropped back to 0.5 bar (cut off limit).
Called an engineer and he said it's the PRV or blow valve which he replaced as it was dripping constantly then quickly scarpered, I watched the boiler and noticed the pressure had gone from 1.4 bar that he'd set it to up to 2.6 bar now this worried me as it's a big increase and the PRV blows at 3 bar.
Now I'm back at square 1 with the same problem of the boiler losing pressure when it switches off. Checked the system no leaks found and no air in rads but PRV dripping again.
Any pointers please ?

 

[jackecole]

sounds like an expansion vessel problem. Have you checked the air charge in it?

 

[misterdubya]

The expansion vessels comminication tube blocks for fun on these. Test the e/vessel as per FAQ's and if its ok, thats your problem.

Mr. W.

 

[mickyg]

The expansion vessels comminication tube blocks for fun on these

your thinking of the ci not cxi as the op has. But yes, expansion vessel should have been charged, I would call back the engineer seeing as his paid visit didnt cure your problem.

 

[toprod]

Hey result BIG thanks to all who replied.

I started at the pressure vessel and checked charge and guess what ? no pressure whatsoever so previous engineer in my opinion isn't worth his salt ! Charged it back up to 12 psi fired up system and pressure is running fine charged to 1.1 bar and when hot and running for 30 mins doesn,t exceed 1.8 bar, no more pressure loss or auto shutdowns.
Just for the record, called the engineer up didnt tell him it was sorted and after the second time id explained, he shrugged it off to a leak under the floor boards said he'd call in and never turned up as i'd suspected !

Thanks again guys its good to know there are still genuine people out there to help you steer round these con men !

Cheers

Toprod

 

[khampson01]

How do I check the charge in the pressure valve on this boiler?, I'm have the same problem, filling it up to 1 bar, 3 hours or so later, 0.5 bar flashing error, checked for leaks nothing, checked for water running out of expansion pipe and all dry. Any suggestion?

Keith