boiler losing pressure - ch pipes not leaking.

[darriusdax]

Hi guys, My client has a leak on this system. It is a big house with 21 radiators all fed by this condensing Remeha condensing boiler. He has had the Remeha approved installers out to diagnose the boiler, they say that there is no leak outwith the pipes, so we isolated the pipe work and put tracer gas in - we got no significant readings any where in the house, and more telling, the gas pressure did not drop over the 2 hrs we had it up at 2.5 bars. ( the client has been losing 1.2 bar per day.) - gas particles are smaller and should leak more easily.
So if there is no leak in the pipes, is there anything that the remeha techs could have missed, and what are the different causes of pressure loss in a condensing boiler system.

Thanks in advance of your advice guys.

 

[Jay Jay]

Main hex leaking through condense quite common now Adays
Good luck

 

[Scott_D]

A leak that only occurs when hot?

 

[darriusdax]

Main hex leaking through condense quite common now Adays
Good luck

thanks jay jay

 

[darriusdax]

A leak that only occurs when hot?

No. the client says that the pressure loss is intermittent, seems to lose pressure worse when the system is cooling down. we did think screw in pipe... but no loss on pipe test. We are going back today to put the pipe system under pressure for a week - independent test with the flow and return isolated in boiler room.
Cheers.

 

[Chuck]

Have you checked what's coming out of condensate drain for the presence of inhibitor, which would indicate a HEX leak?

 

[Darren Jackson]

As Jay Jay pointed out Hex leaking into condense, come across this a few times now. Also quite common is the PRV letting by or flat expansion vessel activating the PRV.

 

[darriusdax]

Have you checked what's coming out of condensate drain for the presence of inhibitor, which would indicate a HEX leak?

good call - would that leak pressure from the main closed ch loop ?

 

[darriusdax]

good call - would that leak pressure from the main closed ch loop ?

Would it be mental to put a we bit of drain dye in the system and then check condensate? just realised i replied to myself..... noob

 

[SimonG]

Pressurised system? Expansion vessel ok? Pressure relief ok?