Heated towel rail/radiator

[polygonum]

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.

[charles]

I think you'd have to runa separate water feed to the towel rail controlled by a valve (and have another valve on the rest of the heating). You could then have a "call for heat" switch in the bathroom which open the relevant valve and the turn on the boiler.

Probbaly less disruptive to geta towel rail that has an electric element as well as using hot water.

[David]

We have TRVs on our heated towel rails.

Not a problem in warmer weather because:

(1) It is a TRV so doesn't kick in if the room is warm

(2) You can always turn it down to "frost protect" if you are worried.

We don't usually need heat in the summer to dry the towels - if you think that you will need heat then the logical thing is to use the electrical option in addition to wet heating.

Cheers

Dave R

[polygonum]

Thank you Dave. If I understand right, you turn your TRVs round the house down, and (if needed) simply turn the towel rail one up. Not having a heated towel rail, I have simply been assuming that in the intermediate months, we will need some heating for drying some the time.

[polygonum]

Appreciated but I have been hoping that isn't necessary.

[harry]

Depending on your system design it may be a "heat sink" & therefore not to be fiddled with. Enables the boiler thermostat to run correctly.

[polygonum]

I am well aware of these issues. It just about could be in the holiday let, but it isn't in the other location.

[Andrew Gabriel]

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.

[David]

Well, no, not quite.

When it is cold enough to need the central heating on, all rooms are controlled by TRVs. They turn the radiators off when the room is just above 20C. This includes both bathrooms. They tend to come on first thing in the morning after the cooler overnight setting.

So far we haven't needed to run the heating just for the towel rails, because when the daytime temperature is in the 20Cs we don't have any issues with the towels not drying.

Both bathrooms also have extractor fans controlled by humidistats so in general the humidity is low enough to dry the towels without any extra heat.

As far as I can see, if the TRVs are set correctly then you shouldn't need to turn them down because they would turn off anyway - just turn up the one in the bathroom and turn up the CH thermostat. This heats the bathroom above normal but should give an extra boost to drying towels.

I think I am struggling to describe a solution to a problem that we have never had.

Cheers

Dave R

[polygonum]

Interesting idea. Do you not find it getting too warm sometimes?

[polygonum]

That sentence alone holds much promise!

Thanks.

[ARW]

You just need the one valve. I recently did such a setup for a customer.

As you say "the towel rail needed a seperate water feed"

The trick to using just one valve is NOT to have the towel rail controlled by a valve!!!!!!

The timer fires the boiler but does not open the valve that supplies heat to the rest of the CH system. Usually bypass required for CH circuits were met but I am sure some Part L regs were broken.

[Adrian]

Ours is a separate zone on the heating.

[polygonum]

Does it have its own timings? Or do you just switch it on and off as you feel fit?