Auto Air Vent - Central Heating

alanobrien

Long story short;

Note; pressurised system boiler.

I have a high resistance circuit on a towel rail which is connected in line on my hot water zone.

The towel rail heats for a while as the hot water comes on then after a couple of weeks does not heat anymore.
I suspect air locks as the circuit goes from the airing cupboard up into the loft over the landing and down inside the wall to the towel rail.

The highest point in the system in the loft is an 18" long horizontal 22mm diameter pipe and i was thinking of putting one of these in the centre of that pipe to help solve the air lock problem.

3/8in Superior Automatic Air Vent (Top Venting) - Duovent (PWW0031) here; http://www.plumbworld.co.uk/229-51

anyone used one of these before and are they any good ?

Its not something i am going to sort out while its cold out, dont fancy draining down the whole system just for this at the moment, but i need to sort it out at some point.

Sometimes i wish i stuck with the old open vented system design :doh:

economiser

I had a problem in an open vented central heating system that was prone to airlocking because of a loop that went to high level. It was on a radiator loop not hot water but it cured the problem. I think it is the pipe run that is the problem not whether it is a pressurised or open vented system.