Alpha CB28

[gas4you]

Now got 2 of these CB28 that are losing pressure regularly. Both about 3 /4 years old. No leaks any where on systems, prv tested and proved ok, pressure in system running normally between 1 bar and 2 bar, all hot water working fine as is ch. Apparently totally normal fully functioning boilers.

Do these Alphas have a 'common' problem where they can lose pressure internally somewhere without any visible signs to the eye

Any suggestions gratefully received

 

[jonseyrs]

Diaphragm on expansion vessel maybe slightly leaking

 

[Paul Barker]

No they don't have a problem of that description.

Fill system up to 2.5 bar, shut flow and return valves. Wait 1/2 an hour, has needle moved? It's the boiler. No? open valves, does it go down now? It's the system.

 

[gas4you]

Any suggestions Paul? pressure is dropping every 2 or 3 days on both!

 

[Paul Barker]

No, it just isn't a known Alpha thing, cb range especially good.

 

[gas4you]

Right then. I'll start from scratch again

 

[clf-gas]

cluching at straws gas4you, could it be a pin hole in HE, visible signs burnt off on firing...

 

[gas4you]

Thanks clf. i had thought about this but I am also clutching at straws and if I had any hair I would be pulling it out now

To make matters even stranger, both alphas are owned by members of the same family.

Think I'll go back to the twilight zone

 

[clf-gas]

Did you get any wher on this one gas4you.

 

[gas4you]

No not yet, still having same problem. Customer is going to put up with it until warmer weather when I can do tests over a couple of days with boiler turned off etc