Problematic Worcster-Bosch Junior 24i Combi.

[MTR]

Drained my GCH today as I needed to mend the drain-off point. Replaced the offending part and all well and good.

Came to refilling the system and it was like pouring water into a bucket with a hole. The guage went up to nearly 3Bar and then back down to 0Bar in about five minutes. I thought I'd left a bleed valve open or sprung a surprise leak but I checked and there were no problems evident. Had a peek outside and the overflow pipe was spurting madly (first time owt has ever emerged from it, AFAIK). There is no air to speak of in any of the rads, AFAICT.

So, the situation now is that any attempt to refill the system is going into the rads upstairs and down but ultimately emptying straight outside rather quickly.

What's the secret ? What an I missing here, folks ?

Thanks very much for any help or advice offered !

 

[Gasguru]

You should only fill the system to 1 Bar MAXIMUM. At 3 bar the safety valve opens.

I suggest you turn the safety valve several times to flush it out and hope it seals. Otherwise you will need to replace it. (Its located at the back of the boiler.)

Also make sure you refill with a quality inhibitor (no cheap carp from the diy sheds) even consider double dosing. This boiler has a major design flaw - any corrosion in the system could one day result in some thing going bang.

 

[MTR]

Thanks. I usually fill to around 1.5Bar. I recall the WB guy telling me to do that so I just always have. However, the system was sounding funny and gurgling alot when I was re-filling it today so I carried on filling. Someone was upstairs with their eye on the only rad which was in the Bleed open position. I expected a bit of a spurt from that and the job would have been done (this rad has been problematic and was 'air-locked' for about the last six months).

Damn, anyway.

 

[MTR]

You should only fill the system to 1 Bar MAXIMUM. At 3 bar the safety valve opens.

I suggest you turn the safety valve several times to flush it out and hope it seals. Otherwise you will need to replace it. (Its located at the back of the boiler.)

Also make sure you refill with a quality inhibitor (no cheap carp from the diy sheds) even consider double dosing. This boiler has a major design flaw - any corrosion in the system could one day result in some thing going bang.

When you say the safety valve (PRV, presumably) is at the "back of the boiler", where exactly ? Or should I just download the pertinent PDF from WB ? And double damn, I was just about to go and get some "cheap carp" inhibitor from a DIY shed in the morning I knew it was the wrong thing to do but I thought I'd cheat...

Cheers again.

 

[Gasguru]

Clip off front plastic trim.

Remove 2 screws.

Lift off outer case.

PRV is at the back - turn red cap several times to flush through valve.


Use Senitinel/Fernox/Aqeous Logic

 

[MTR]

Clip off front plastic trim.

Remove 2 screws.

Lift off outer case.

PRV is at the back - turn red cap several times to flush through valve.


Use Senitinel/Fernox/Aqeous Logic

Will do. Thanks again.

 

[MTR]

Have found what appears to be the PRV but how the blazes can I access it to turn it ?

 

[MTR]

Presumably, by "turning it" we are talking in the direction of the little arrow on the head of the cap and all in that one direction only ?

 

[MTR]

Answered both my own questions and pressure now at a mite over a bar and steady for now.