Ideal mini 24 losing pressure fast

[miket2001]

Hi,
I have an ideal mini 24 boiler that loses pressure almost instantly once filled. All our pipes are above the floor and i can detect no leaks, all valves are tight and no aparent leaks. When i bled the radiators upstairs they were quite low and the water seemed fizzy. The ones downstairs didnt take much bleeding and the water flowed as normal. I pressed the shrader valve on the expasion vessel and only air came out, quite high pressure. I placed a sandwich bag over the outlet pipe that comes outside, i left it over night and no water was in it.
Does anyone have any ideas of what the problem could be or any other checks i can make?
Thanks in advance.
Mike

 

[miket2001]

Anyone please help....

 

[1983]

its got to be going somewhere,
could be a leaking heat exchanger, the water will drain through the condensate pipe. with the boiler off disconnect this below the boiler, pressurise and then see if any water starts coming out. when you say instantly can you see the gauge dropping?

 

[miket2001]

Thanks for the reply. The pressure gauge goes down straight away, you can see it reducing. All the rads upstairs make a gurgling noise about 10 mins after putting heating on. It sounds like all the water is draining downstairs? Where would the water go if the exchange was faulty, is it down the waste pipe?

 

[ianmcd]

is it a mini ? or a mini HE ? they are two different animals

 

[miket2001]

I'm not too sure, it's 7 year old if that helps! Sorry not at home so can't check at the minute.

 

[ianmcd]

do you know if it has a white condensate pipe coming out of it either going to a drain or a soakaway ?

 

[miket2001]

There's a white pipe that comes out of the left hand side into the water drain. Dunno if that helps? Thanks.

 

[ianmcd]

OK sounds like you have an HE, if you have carried out all the other checks PRV expansion vessel and you are losing water that fast it sounds like the recuperator has split, the white pipe going into the drain, if you can break a joint on that then do that and try and pressurise the boiler, if the water that you add comes out of that pipe then it is indeed the recuperator, if no joint to split try feeling the pipe if it loses the pressure that fast, one last thing to check is the actual drain down point of your system try and locate that and see if it is coming out there

 

[miket2001]

Brilliant. Thanks for your help, I'll do the checks tomorrow when kids at school. Really appreciate your help mate. I'll update the results...