combi pressure

[carljb]

I have a worcester 240. When in use the pressure is approx 1.5, when boiler shuts down pressure drops to 0 and then pressure increases to 1.5 again when boiler ignites
will this cause a problem? how do i cure it.
thanks

 

[corgiman]

your expansion vessel may be at fault, try topping it up to 1 bar cold and see what happens when you fire the boiler up

 

[pierrot]

It may be a faulty pressure gauge.

 

[ChrisR]

See FAQ's

 

[carljb]

Thanks for replies.
When topped to 1.0 bar when cold then fired up the pressure increases to 3.0 bar, opens the pressure relief valve and trips the system.
Can the expansion vessel be repaired, re pressurised or does it have to be replaced?

If all else fails i`ll look at replacing pressure gauge.

Thanks again

 

[corgiman]

may be able to repressurise it dont forget to reduce the pressure in system if you do

you will probably need to replace it.

might be an idea to pop a 12lt external one on

 

[s4ndy]

my boiler does the same! Mine's not a combi but it drops to 0 when it's finished. When I top it to 1, it goes to 3 when it's on!

I leave it for nearly 3 months but now the boiler starts making some horrible noise when it starts, and I'm now still looking for a liable plumber to fix the problem. So I suggest you to fix it now before it goes any worse later!!

 

[carljb]

expansion vessel charged to 1 bar using a footpump.
hey presto everything is working fine now.
THANX EVERYONE