In article ,
polygonum writes:
For various reasons, including using the things fitted in a holiday let,
I have become interested in heated towel rails.

The towel rail in this location is a decent size and would appear
adequate to heat the bathroom. It only heats when the central heating
combi boiler is on. Even at this early part of the year, this week we
have felt little or no need for general heating.

The towel rail itself has no controls on it (yes - lock shield but not
TRV, etc.). So all we can do is go round the place, turn down the TRVs
on all radiators, and play with the room thermostat to get the CH
running. Then the towel rail warms up nicely - if not too much!

Far more handy would be if there were a push-button which allowed you to
get the towel rail heated for, maybe, half an hour primarily to warm and
dry the towels. Without having to do anything else.

Another place uses TRV on the towel rails - at least you have local
control in the bathroom. But even then, you have to remember to turn it
down again and it might be rather more than is needed in warmer weather.

Is there a satisfactory answer to towel rail control? I am well aware of
the electric option but want to see of there is another answer.

I don't know if it's deliberate (I suspect not) but one of heating
systems I look after for part of my family has the bathroom radiator
directly across the boiler output so it heats in the case of heating
or hot water demand, so in the summer too. Its connection to the
pipework also means that when the boiler is off (most of the day in
the summer), it gets gravity heated by reverse flow in the hot water
cylinder coil, drawing stored heat from the cylinder like a thermal
store. They find this quite useful for towels, and the gravity feeding
only makes it warm, not as hot as the hot water cylinder tank.

I actually liked the concept of the bathroom heating directly across
the boiler output, so I did that when I put my own heating in (with
a TRV in my case), although I don't have the stored water tank to
keep it going when the boiler is off.

--
Andrew Gabriel
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