Why not just run the present towel rail from a timer which turns it on in time to heat the room before you use it?
The house that I now live in has radiators everywhere
except for the bathroom ... Which genius thought that the room that you get naked and wet in is the only one that does not need heating!
Anyway, an electric towel rail has now been fitted. It is only 750W so it does take some time to take the chill off the room. I either switch it on using a timer in advance of getting up, or do it manually before a bike ride so the room is warm for my post-ride shower. I can't see the problem with that.
If you insist on a more powerful solution, why not use a 2 kW fanheater to blast the room for a few minutes before you go in? I hate fanheaters because they are noisy, but that doesn't matter if you are not in the room at the time, and they ARE very effective. [DAMN - '
not read previous post' error!

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