DIY Doctor UK DIY Forums

Hi - new to this forum so be gentle. I know it's been asked loads of times but I'm getting a bit cheesed off and need some new input.
We recently had a new Bosch Worcester greenstar 42CDI boiler fitted. After it was comissioned, the fitter told me we may need to re-pressurise the system a few times after bleeding the rads to get all the air out of the system. After a month, we are still losing pressure - takes about 24 hours to lose the lot.
Immediate thought was a leak, although we haven't changed/altered anything except had new boiler fitted.

No visible evidence of any leaks. I have concrete floor so all ground floor piping is surface mounted. Upstairs - no discolouration of wall/ceiling, damp carpet - not a sausage!. What troubles me is that it takes quite a tidy amount of time to refill the system so where is all the water going?

Have also had a bottle on the venting pipe outside for 24 hours - nothing.

Can anyone suggest ANYTHING else I could try :?:

Check the condensate discharge - sometimes the secondary heat-ex can split and the water is lost this way.

But - i'd put money on it being a leak. It doesn't take much of a leak to lose the system pressure.


htg

[quote="htg engineer"]Check the condensate discharge - sometimes the secondary heat-ex can split and the water is lost this way.

But - i'd put money on it being a leak. It doesn't take much of a leak to lose the system pressure.


htg[/quote]
Thanks htg - pity you're not a betting man :P

I got the installer to come back again and he put some stuff in the system that seals small leaks - worth a try as we didn't want to go down the chip board floor route :shock: . Anyhow, for others who suffer the same problem, this seems to have done the trick. We have had no pressure loss for 3 days 8)

DeeJay -

I have the exact same problem with my boiler, I've been thinking there might be a leak somewhere in the system, but I can't find any visible traces of it.

Can you give me the name of the person who put the "stuff" in it that repaired the small leaks? or could you find out what the stuff is called so that I can try it in my system?