asked this question earlier but cant find where its gone?
the overflow pipe outside was leaking and the pressure dropping so i replaced the pressure release valve. the pressure now goes up and up when ch/hw is called for?
any ideas?
cheers

chris gray, February 2010

the gauge was working fine as it turns out, it was simply not measuring it. it only began to measure it when i put some water into the system, at which point it went upto 25? i released some more air and topped up the water. im guessing i released too much air as the gauge wouldnt/couldnt read it now. guess what.. the pressure gauge slow rose as i heated the system up again.
either i let too much air out - judging by the lack of response from my pressure gauge, or.... dunno..
when i put the tyre pressure gauge on the vessel valve there is no reading.
ive had the system running so im going to have to wait for it too cool down now and try again what ive done

chris gray wishing on a star, February 2010

jeez
forgot to depressurise the system when i disconnected the prv, not a good idea. pcb all wet now. i should of stopped there.
depressurised and persisted, there seemed to be a whole lot more water this time round, when the flow abated i attached the pump and gave it a couple of pushes, in the end the water became, browny/yellow? hopinig ive not emptied it of an inhibitor?
the pressure has built up in the vessel, my ruddy pressure gauge wont work now.
im going to go find/buy another.
im guessing i have put far to much air inito the vessel, as when i took the pump off i could hear a release of air from the valve, i pushed the pin in for a moment to release the build up of air and it seems fine, just need to measure the amount of pressure i have put into the vessel now.
if the discoloured water is from the inhibitor (may just be rust) how would i go about reinstating this?

chris gray in response to john, February 2010

ps
found my vessel valve, (basically same as a tyre valve - hence why you would attach a tyre pump) pressed the pin inside - no air + no water. no water being a good sign as im guessing/hoping that the diaghram hasnt split.
would it not be possible to pump the air through the system and into a rad and bleed the air through that?
just getting the pin back in when i renewed the prv was a pain in the backside - just a thought.

chris gray - again in response to john, February 2010

thanks for your response john.
im a sparky so think i know everything.
let me get this straight:
so i need to undo the prv, gain access to the valve on the expansion vessel and attach a tyre pump (ive got a foot one) and pump the water out?
im guessing that the water is going to come out where the prv is?
once the water is out, leave the vessel with 10lb of pressure inside it (just curiuos how that is going to be maintained with the prv off) and then reattach the prv.

the pressure was rising to nearly 3 bar last night when i decided it best to turn the thing off.

i have done continuity checks on the aps, fs, harness and everything i could gain access to all which were fine.
im guessing the only thing left is the vessel, i have had this boiler in my house before i bought it a good 8 years ago.

in response to john, February 2010

before replacing the pressure relief valve it is good practice to leave the old pressure relief valve open and put a tyre pump on the valve of the expansion vessel and pump it out as they can fill with water, it doesnt allways mean the bladder inside has perrished, it only needs a gently pump up once the water is out approx 10 lbs not psi then replace the prv repressurise the system to approx 1.2 bar, it is normal for the pressure to raise half a bar when the boiler is hot and then drop down again when it cools. hope this helps.

john, February 2010