Cold shower rail with heating on, but ok with hot water only

[cdl888]

We have a tall chrome ladder type shower rail in our 1st floor bathroom which works absolutely fine all year when we only use the hot water, but stone cold as soon as we start using the central heating.

We have tried bleeding it regularly to no avail.

To make things more confusing, some days it warms up, but mostly it remains cold.

The chap that installed it thinks that it's just because it's a tall ladder and that the system is struggling to heat it, but even the pipes at the base remain stone cold.

Cold towels I can live with, but the bathroom gets very damp in the winter which is less appealing!

Any ideas?

 

[Whitespirit66]

What type of system do you have. If you have a hot water cylinder in your airing cupboard, it's possible that the towel rail is plumbed into the primaries for the cylinder, and not plumbed into your heating pipes. If you turn on your hot water, and the rail starts heating up, then it is on the hw primaries.