worcester/bosch 350 domestic boiler

[dailimbo]

I am looking for help to solve a problem that I have with my boiler.
When the pressure gauge reaches just above 3bar (about 2 lines past ),I lose about 2 cup fulls of water out from the pressure relief valve. Once this amount has come out the boiler works fine. I have to top up each day to bring it back to the required 1bar working pressure.
I have changed the pressure relief valve and it is still the same.
Can anybody help.

cheers dailimbo

 

[corgiman]

check the expansion vessel

 

[dailimbo]

Hi Corgiman,
Managed to get a new expansion vessel from woseley parts centre, the make is zilmet. the old vessel had a working pressure of 4 bar, the new one is only 3 bar. Woseley got in touch with Worcester boiler people last week because the first expansion vessel they gave me was completely wrong. The pressure relief valve is also a 3 bar setting.
I installed it yesterday and repressured the system to 1 bar, then fired it up. It worked fine the pressure only built upto just over 1 1/2 bar.
After it working all evening and switched off, the pressure dropped back to just over 1 bar. Needless to say that no water came out of the pressure relief valve. this morning the pressure was still just over 1 bar
Thanks Dailimbo

 

[corgiman]

Well done you