Replacement of radiator with towel rail / BTU ratings

[adobbing]

First post and little or no experience of plumbing, Help needed please!

I am looking to replace a conventional radiator in my mother’s bathroom with a towel rail radiator.
The existing radiator in the bathroom is 500mm x 500mm, I think it is a double panel.
I believe it is the radiator used to dump excess heat as it has no thermostatic valve on it and she tells me it gets hot at different times to the other radiators?
Width is going to be a limiting factor in what towel rail radiator can be used also, as bathroom door opens inwards onto the wall the radiator is on. 500mm wide would ideally be the widest size.

There seems to be a significant difference in the heat output between conventional radiators and towel rail radiators.

Is it crucial to choose a radiator with similar BTU heat output?
I have been looking online to try and work out what the existing radiator BTU output is and what a comparable towel rail would be.
I think the existing 500mm x 500mm radiator must be around 2500 BTU.
A 500mm x 1100 towel rail radiator is I believe 1788 BTU, would this lower BTU rating cause any issues?

Apologies if this has been answered previously, a quick search on the forum topics didn’t reveal any answers.

 

[david17uk]

In theory you should try to replace the rad with a similar BTU sized towel rail, however, it's not always possible.

Get as close as you can to the existing btu output.

 

[adobbing]

In theory you should try to replace the rad with a similar BTU sized towel rail, however, it's not always possible.

Get as close as you can to the existing btu output.

Thanks for your response!

Would 1788 BTU be close enough to 2500 BTU to not cause any issues?

 

[david17uk]

Probably your only option

 

[TicklyT]

A towel rail swathed in towels will have a significantly lower heat output than the manufacturer's quoted output, so you may need to aim higher.

 

[BingoBongo]

it also wont convect and heat the room in the same way.

 

[david17uk]

Couldn't you just put a wider one in (so it's behind the door if the door's open)?

 

[adobbing]

Thanks for responses.

An update!

After further investigation, I have found that the existing radiator is a single convector 500mm x 600mm.
I estimate its output to be around 1677 BTU from comparison with one the B&Q website.

So a 500mm x 1100mm towel rail radiator with an output of 1788 BTU, again from B&Q website, is I think close enough.

The existing radiator currently has a towel rail above it, which has towels hanging down over the existing radiator most of the time.
So I think usage will be similar and the issue about reducing the heat output will, although being significant as advised, be similar to its current usage.

Thanks gain for help and advice.