Bathroom radiator keeps on needing to be bled

[nickldn]

Hi,

I recently had my bathroom radiator replaced with a tall spiral type towel rail.

The problem is, the top couple of rungs are cooler than the rest. This is cured by bleeding the radiator, but a few weeks later re-occurs.

This did not happen with the old radiator.

The way the plumbing is done means the radiator heats up when the hot water is switched on, so towels are dried even in the summer.

There is a thermostatic valve on the radiator to control the heat.

Could anyone tell me why I keep on needing to bleed the towel rail?

Many thanks,

Nick

 

[Axel]

1. Maybe air is getting sucked in through a new joint on the connection to the towel rad.

2. Air was getting in, or gas being generated in system in the first place but didn't go to the old rad as flow rate has changed, however in that scenario the air must have been ending up in one radiator or another.

 

[nickldn]

I think the system was fine before and there were a number of new joints created for the new rad.

Unfortunately the majority of those are under the floor, or inside the wall.

Is there an easy way for me to diagnose where the air leak could be?

Also, could water be leaking out through the same joint?

 

[Axel]

Is it a sealed system or open vent?

I remember that when I altered some pipework in my house, air started bubbling up in a bedroom radiator that previously did not have it, but this air had previously been appearing in a different radiator.

 

[Red_Man]

Buy a

http://www.heatandplumb.com/acatalog/Aladdin_Autovent__Vertical_Radiators_.html

Save yourself some hastle.

 

[Axel]

Hmm...gets rid of the air but does not deal with underlying cause of problem. Air in system is not good for long term health of heating system.

 

[nickldn]

Yes, the air is my worry. What sort of problems can it cause in the long run?

This morning I've tightened up the external bolts, which to be honest were fairly loose, and re-bled the rad, we'll see what happens next I suppose.

If I'm very lucky it'll solve the problem.

All the joints in the copper pipes under the floor and in the wall were soldered, so I'm hoping they're airtight, but who knows.

I can't face (afford) to rip up the tiled walls and floor to try and find a leak, so if this doesn't work I'll need to invest in the auto-bleeder and hope the rest of the system doesn't die.

 

[Axel]

A sealed system won't suck in air. Pump position in open vented is also critical.

Probably isn't sucking.

Just me projecting my CH woes onto others!!

 

[lifesagasman]

a sealed system can suck in air at the same points that are leaking/weeping

 

[shawd]

A bit of air collecting in a rad , not the end of the world ,,, Most people have to bleed a rad at sometime, dont worry be happy

 

[Axel]

Air...corrosion...sludge...gloom...doom...