Excessive Radiator Bleeding

Wig

Combi boiller

I seem to be bleeding the upstair rads excessively. So far I did it weeks ago, and then I noticed cold again yesterday I bled yesterday and again this morning, fully open bleed valve with no water for quite a few minutes before water finally appeared (I blame the microbore pipe I hate that stuff) Is there a reason for the air in system?

When I re-pressurise what pressure am I aiming for?

Thanks

bris

You have a leak in the system, pressure between 1-1.5. bar. Nothing to do with the microbore, a leak can happen to any size.


Get a paper towel out and go round all the radiator valves, there is a good chance one is leaking down the pipe and under the floor.


Also have a look under the boiler at all the connections.


The reason you need to bleed the upstairs is because of gravity, when you lose water the highest point drains first.


P.s Sorry forgot about the PRV, have a look outside where your overflow from the boiler comes out, look for a drip, this is a faulty pressure relief valve.

nofoollikeold

1. You have a sealed system, bris is right.
2. If you have an open vented system (small feed and expansion (F&E) tank in loft), then it is likely that air is getting into the system via the F&E. Check that there is water (about 100mm / 4inches) in the base of the tank, and that water flows in through the inlet valve if you momentarily push down the float of the float operated valve. Its also possible for air to get in via the vent pipe, but sorting that out is a bit more complex.

Wig

There is no tank in loft, just a combi,

It really is airing up quickly, I have just been bleding upstairs again, most of them had air in them some a lot of air.

I will check outside because there is no sign of an internal leak....yet.

boiler is constantly saying 1.5 bar, I have not had to re pressurize it.

There is evidence of water on the small white pipe outside, it's not dripping now but earlier today maybe, have to check again when I put heating on tomorrow.

Boiler has been problematic recently getting it to fire up, but it eventually does.

It's a glowworm.