fitting new pressure relief valve

[spaglemon]

to fit a new prv to a potterton puma 100e boiler as far as draining goes can i switch off the boiler release the pressure in the system using the faulty prv , switch off the main water stopcock , open the hot and cold taps , and drain from the drain screw below the pump , would that drain the boiler enough to let me fit the new prv ?

thanks

 

[powell30]

A PRV spagleman is a safety device. I for one wouldn't be happy telling you how to do this. I suggest you get a RGI to come do it. Others may feel differently, thats up to them, but you need to make sure you and your family are safe.

 

[spaglemon]

thanks for the advice , i thought this was a fairly straightforward job and this being a diy forum would be a logical place to seek some advice , please don't take this the wrong way as i really am grateful to anyone including yourself who takes the time to reply

thanks again

 

[seco services]

some will help others won't.

you'll only need to drain the heating side.
not the dhw or stopcock

 

[spaglemon]

thanks , to drain the heating side i have to shut off something though ?

 

[Mr Smyth]

No,
As Seco says, just drain the the heating side.

Turn the boiler off, probably worth making sure it is cold/cool.
Isolate the electrics, just in case.
Let off the system pressure via the faulty PRV
Unscrew the plastic part of the PRV from the metal body. Probably no need to remove the whole valve.
Be ready to catch a little water.
Clean the valve seating.
Screw in the new valve head.
Refill and vent the system

The side panels of pumas remove v easily to improve access.

Only issue I can see is the reason behind the PRV failing in the first place?

Is the expansion vessel pumped up?
Is the pipe leading to the vessel free of blockages?

I'm sure there are FAQ's about this

 

[spaglemon]

thanks mate , the system pressure was dropping gradually which meant re-filling quite often , eventually traced the leak to a couple of radiators with a couple of small weeps ( never noticed until i saw the carpets around the pipes were changing colour , tightened up the leaky joints and i suspect the continual re-filling has caused the prv to get dirt in it as the outside vent pipe is dripping slightly causing the pressure to drop again , i've ordered a new one , i didn't realise they could be cleaned , others had suggested that once they start to leak they need replacing , the pressure vessel seems ok , i'll be flushing the system and adding inhibitor after all the re-filling recently

thanks again

 

[spacethegas]

don't add inhibitor straight away. wait 3 or 4 days until you are sure the problem is solved, then drain & add.

 

[spaglemon]

fitted the new prv , seemed pretty straightforward , went to check pressure in the pressure vessel and when i unscrewed the valve cap some air escaped , faulty valve ?maybe why the system was losing pressure in the first place , replaced the valve and pumped in 14 psi , re-filled system and all seemed well ( wish i'd stopped there ) thought i should bleed the pump and when i unscrewd the centre nut a bit some water dribbled out and there was a funny noise (ticking or clicking) in time with the pump internals spinning , screwed the nut back in but the noise hasn't gone away , took the pump off and stripped and cleaned it as much as i could , with the pump off when i spun the blade i could hear the noise inside the main body of the pump , any ideas ?

cheers

 

[GforceJames]

New pump, bearings wearing.

James

 

[spacethegas]

expansion vessel should be pressurised to 0.5 bar or just over. thats roughly 8-10 psi