biasi boiler pressure loss.

[Nealec]

Biasi
I have a biasi M96.24SM/B2 Combi that keeps losing pressure
I have no water leaks and the boiler works fine if i bring the pressure up
but it will go down from 1.2 bar to nothing in half an hour
I think i need help

 

[apl]

have you noticed any leaks outside your house from the blow off discharge pipe.

 

[Nealec]

Hi
No leaks from anyware
i shut all the rads off as well just to see if any air was escaping from any joints but all seam ok
Thanks

 

[wiggikins]

There MUST be a leak somewhere, Have you had the floorboards up and inspected all pipework

 

[Goldspoon]

Blow off pipe to outside: put a clear plastic bag over it held by elastic band - see if it fills with water when pressure drops.

 

[wiggikins]

Blow off pipe to outside: put a clear plastic bag over it held by elastic band - see if it fills with water when pressure drops.

From 1.2 bar to 0 in 1/2 an hour ,if it were the blow off i think it'd be a bit noticable what say you