Vokera Excell 80SP -Intermittent hot water

[jack_s]

regardless of what the book says you shouldnt use the prv as a drain

check its not dripping when you repressurise the system

Guess what, the Safety Valve is dripping !!

TBH I have occasionally found small amount of water under safety valve area (1/4 of a cup) occasionally in past & wondered why CH pressure was dropping. Although I never saw it dripping in past.

Is there anything I can do to get it sealing properly ??

Should I just replace it ??

From Vokera manual it looks easy enough to replace, says to loosen grub screw at base & pull valve forward, replace in reverse order.

 

[kevplumb]

From vokera manual it looks easy enough to replace, says to loosen grub screw at base & pull valve forward, replace in reverse order.

don't forget to relive the pressure first

 

[DP]

I've tried repressurising boiler, but pressure on pressure gauge is not rising.
(Both CH flow & return valves under boiler are closed.)

Am I dreaming above or is this post a wind up.

 

[jack_s]

I've tried repressurising boiler, but pressure on pressure gauge is not rising.
(Both CH flow & return valves under boiler are closed.)

Am I dreaming above or is this post a wind up.

I thought 2 valves just isolated main CH system, thought you could repressurise like that.

Opened valves, all's ok.

 

[jack_s]

From Vokera manual it looks easy enough to replace, says to loosen grub screw at base & pull valve forward, replace in reverse order.

don't forget to relive the pressure first

Where is the grub screw on the Safety Valve, can't see it ??

 

[nickso]

underneath.

 

[jack_s]

underneath.

I've just bought the Vokera 4250 valve, it's a screw fit.

My boiler is Vokera Excell 80SP 4709416.

Only manual on Vokera website is for next variant Vokera Excell 80SP 4709417, which uses push-fit valve. That's why I thought mine may use push-fit as this manual says to loosen grub screw & pull valve forward.

Mine uses screw fit (4250), next variant must use push fit (8433).

 

[jack_s]

...

 

[jack_s]

underneath.

I've just bought the Vokera 4250 valve, it's a screw fit.

Mine uses screw fit (4250), next variant must use push fit (8433).

I tried to remove Safety Valve, but it does not want to move.

I'm wary of using too much force in case something breaks off.

Any suggestions on removing stuck/corroded nut/screw fitting ??
.

 

[kevplumb]

heat is fave just depends how you can apply it

 

[jack_s]

heat is fave just depends how you can apply it

Does this usually work ??
How much do you heat ??

I've read to heat just the outer fitting to red heat so it expands, not to heat inner fitting as that could make it more difficult.

 

[DP]

Jack, it is time you get a pro to come in to your rescue.

You boiler needs help, so do you. There is only so much a DIYer can do on their boiler.

The manifold needs to be removed for work to progress on it. Apply heat in that confined space and you will end up with bits ready for Walker's crisp packet.

 

[nickso]

if you insist on changing the whole thing brute force is the way forward.

i would change the plastic bit and save the hassle. probably not recommended for you though.

 

[jack_s]

i would change the plastic bit and save the hassle. probably not recommended for you though.

Does it just unscrew ??

 

[jack_s]

i would change the plastic bit and save the hassle. probably not recommended for you though.

Replaced plastic bit of safety valve.
That worked a treat !!

Old plastic bit came off nice & easy.

Dripping has stopped & system is holding pressure.

Thanks