falling pressure in sealed system

[servo]

Hi,

I have a Worcester R28 System boiler, only about 2 months old. It has an integral pump and diverter valve so has two separate loops, one for the indirect hot water tank, one for the radiators.

I replaced most of the radiators from the old system and did most of the new pipework around the boiler. A corgi plumber checked it and commisioned it for me as well as powerflushing the old pipes.

Every week I have to add more water as the pressure drops to below 0.5 bar, when it starts at 1-2 bar.

I have checked all the connections I can and haven't found any leaks.

Does the air vent on the expansion vessel need to be open (it is)?

Could the water be evaporating from somewhere without dripping?

Should I disconnect the filling loop?

There is a quirk with the hot water taps as they splutter like there is air in the pipes. Could this be a clue?

Hope you can help.

Thanks,

Gary

 

[ChrisR]

>I have checked all the connections I can and haven't found any leaks.
Keep looking.
Check the pressure relief pipe through the wall isn't wet.
Does the presure go down while the boiler is not being used?

>Does the air vent on the expansion vessel need to be open (it is)?
Yes. SOmetimes they're moist but don't let that much out.

>Could the water be evaporating from somewhere without dripping?
Yes. Rad valve stems typically.

>Should I disconnect the filling loop?
Certainly.

>There is a quirk with the hot water taps as they splutter like there is air >in the pipes. Could this be a clue?
No. Indirect system not a combi. That's just bad plumbing!

 

[servo]

thanks for the reply!
Will try and turn it off for a while see if it drops still.
Will check joints again.
Have now disconnected filling loop.

Bottom connection to HW tank was leaking when I first turned it on. Quick tighten of the nut stopped it. Will tighten it a bit more.

Thanks