Towel radiator constant bleeding of air

[Eyespy999]

Hi, I was wondering if anyone has any advice please.

i have a towel rail radiator, every few weeks it goes cold at the top and I end up bleeding quite a bit of air from it.

No pressure drop on the system just air! It's been like it for ages but looking for a solution.

Thanks

 

[Best]

Towel rails do pick up the air out of a system.
That would be understandable if your system is open vented, as the system will constantly absorb and release air as it heats and cools. But if it's a sealed system, as you mention no pressure drop, then air is being absorbed somewhere.
Only exception is is system has been drained and refilled with fresh water for work done, - where air will gather for a few weeks
Auto vents or leaks at valves or boiler could cause air ingress. Or gases from sludge in system, but rare

 

[Eyespy999]

Great thank you for the swift reply.

 

[stephens]

Current and last house both had pressurized combi systems but both did this, bathroom radiator only.

Both cases it did not smell gassy so was not from corrosion of the system. I think I read that air can be taken in on the return side of the pump without a leak showing, not sure if that is correct.

Last house tried changing both lockshield valves on it (radiator) but still filling with air!
It was only when it rusted out (where towels were on it) and we replaced it that it stopped abruptly/completely. So I presumed that air had been getting in at the Bleed valve at the top or oppposite side.

This house move in and large bathroom towel rail taking in air, lots!
Got a heating engineer to replace a suspect lockshield valve on another radiator and reseal the Bleed valve and opposite side of the towel rail. No more air in the towel rail.

Whatever you try make sure to reseal the two at the top, it's quick and cheap to do.