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M

martin101068

Hi...
I have a Worcester Bosch 350 Combi and for the fourth time now in 12 Years I'm having to have the expansion vessel replaced as it seems the membrane inside the expansion vessel has split. I have checked this by pressing in the valve on the air side of the tank and find water coming out.
When the heating is off the pressure in the system drops to zero and I have to re-pressurise it before the heating system will switch on. Then the system over pressurises and the pressure release valve opens and leaks the excess water / pressure outside.
I have 10 large ish radiators in the house, 2 of which are kick space heaters of 800mm (biggest radiator been 2000 x 600 double in the conservatory)
This problem may of started around the time of having the conservatory radiator fitted some 9-10 years ago....
The last expansion vessel I had replaced lasted 4 years and at the time I had them put some fernnox in the system.
Why is it constantly doing this....
I have been told that I need a larger external expansion vessel of about 18 or 24 ltrs and to bypass or remove the smaller 10 Ltr internal one altogether as it's not big enough.
What other or different options am I best advised to do...

Many Thanks

Martin
 
Last edited by a moderator:
Re: Worcester Bosh 350 Combi Expansion Vessel...

You could try leaving some radiator partially empty,
with air in the top part of the radiator to act as an expansion vessel.
perhaps a radiator that is not fully used or is always turned don.
 

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