Hi,

apologies similar topic again. We had a brand new worcester CDi 37cdi installed in the airing cabiner upstairs. 7 new radiators and new pipework installed while changing boiler from gavity feed system.

The system does not seem to hold pressure. The installed has already been twice. Lifted floor boards still not joy finding any possible leak. All The radiators are unconfortably hot to touch, is that proof that there are no leaks. No pipes in the concrete. No wet patches in the ceiling downstairs.

I cannot see any water dripping out of PRV. The problem is when I pressure system to 1.5 when CH is on the pressure goes up. But over night when the CH is switched off the pressure falls. The pressure goes from 2 to 0 in 2-3 days.

Could anybody please suggest what is wrong with the system. The system was installed just around 4 weeks ago and paid a fortune for getting the heating sorted. The house is warm and do get warm water, but pressure lost.

if the whole system is new keep getting the installer back till he fixes it.

Thanks. The installer is coming back on tuesday. 1st time around he lifted the floor boards to check for leak.

But second time he just put the boiler on full steam and felt the radiators and said, if the radiator is boiling hot, that points towards that not having a leak, is this right.

While most rads do not have any airlock, two rads post drop in pressure seems to have lot of air which needs to be bled every week. No visible leaks below either of them though.

Hi all,

To test ch, i isolated ch from boiler. Left the boiler for 10 hrs. The pressure this morning was 1.5 bars. As soon as i opened the valve the pressure dropped to 1 bar.
Does this indicate leak in ch rather than fault in boiler.

When cold checked all rads. Two new rads had droplets of water and black stain. Is this where the leak is. Mind you i am topping litres if water and only droplets at two rad valves.

No, pump up pressure and shut the flow and return. If no loss showing on boiler, then definitely heating side.
How long is it taking the pressure to drop.
If it is a while, then it only needs to be a very small weep on a rad valve etc, which is maybe drying out, when the heating is on

Hi. The pressure lost every three days. But still not conviced few tear drops at rad value accounts for loss in pressure. I wish i am proves wrong.