One cold towel rail

[lostmystickinsect]

I am trying to resolve a problem I have with the heated towel rail in my upstairs bathroom. All the radiators in the house seem to work fine except for this one. I can't get it to heat up! The problem started when we first switched the heating on after the summer.

I have a Baxi condensing combi in an old 30's semi. The towel rail will not heat at all, even the pipes leading to it do not seem to be warm.
If I bleed the towel rail so that the water is gushing out, it will eventually start to get hot, but as soon as I close the bleed screw it goes cold again.

I have seen other posts with similar problems but they often seem to be due to faulty TRVs. This towel rail has no TRV (as far as I can see) - it is a Hudson Reed Marquis and it has two valves/taps at the bottom - I'm not sure what these do? Sorry to sound a numpty - I am just a mum trying to get the bloomin' thing working again.

I have tried bleeding every radiator fromdownstairs upwards. I have also tried switching all rads off downstairs to see if it kickstarts something? No joy.
Any advice would be much appreciated.

 

[gash2024]

you might have an air lock, close of your other radiators and turn your pump up to max and give it a blast for 5 mins.
It worked on mine

 

[lostmystickinsect]

thanks for that - I've kinda tried that by switching off all other rads, and I increased the system pressure to safe max. I assume that is what you mean by turn pump up to max?
Still no joy.

 

[lostmystickinsect]

Can anyone suggest whether it is a problem with the towel rail, or if it is more likely to be a system problem? thx

 

[JohnD]

1) Verify that the valves at each end are not excessively screwed shut.

2) turn off all the other radiators and see if this one then heats up.

If it does, you have a problem with the flow. Balance the other radiators so that this one heats up by about the same amount. See no. 2
//www.diynot.com/forums/viewtopic.php?t=37170

If not, did it ever work properly? did something happen before it went wrong, or did it gradually get worse over several years?

what happened when you tried to bleed it. Did air come out? Or water? Did it squirt out forcefully? what colour is the water when you bleed this and other radiators? Is this radiator the highest in the house, or in an extension, or was it added after the others?

Possibly you have a sediment blockage. It is possible to do a chemical clean as DIY plumbing, and I would always suggest you start with this (at a cost of £15 plus a few hours DIY) rather than splashing out £hundreds on paying for a powerflush.

 

[gash2024]

You beat me to it, i was just going to say it could be sediment.
It should be easy enough for you to flush the system out as you will be using the heating alot this time of year so the cleaner will get chance to do its work.

 

[lostmystickinsect]

1) Verify that the valves at each end are not excessively screwed shut.

2) turn off all the other radiators and see if this one then heats up.

If it does, you have a problem with the flow. Balance the other radiators so that this one heats up by about the same amount. See no. 2
//www.diynot.com/forums/viewtopic.php?t=37170

If not, did it ever work properly? did something happen before it went wrong, or did it gradually get worse over several years?

what happened when you tried to bleed it. Did air come out? Or water? Did it squirt out forcefully? what colour is the water when you bleed this and other radiators? Is this radiator the highest in the house, or in an extension, or was it added after the others?

Possibly you have a sediment blockage. It is possible to do a chemical clean as DIY plumbing, and I would always suggest you start with this (at a cost of £15 plus a few hours DIY) rather than splashing out £hundreds on paying for a powerflush.

I have just done another test. I turned off all the other rads, with heating on full, yet the towel rail did not get warm.

So, I bled it again. No air comes out, just lots of water at force! The water is pretty much clear. This is what happens whether the other rads are on or not. A few pints of cold water come out, then the towel rail begines to get hot.

So, it mustn't be a balancing problem. In answer to your other questions - it is on the first floor as are several other working rads. Interestingly, it was fitted after the others, when we had a bathroom refurb. I don't think there was a radiator there before. Why would this make a difference? We have had it about 3 yrs and it has worked fine in the past, although I do remember having a similar problem when we switched to winter mode last year - it seemed to fix itself by lots of fiddling/bleeding.

So, on your advice I will get the hubby to do a chemical clean - when he is back in the country!! My only other thought is that the return(?) valve, by this I mean the equivalent to the lockshield(?) valve on a normal rad, is stuck or stuffed?! I'm going to ring Hudson Reed tomorrow and ask how I can check this.

Thanks all for your help.

 

[JohnD]

I have just done another test. I turned off all the other rads, with heating on full, yet the towel rail did not get warm.

So, I bled it again. No air comes out, just lots of water at force! The water is pretty much clear. This is what happens whether the other rads are on or not. A few pints of cold water come out, then the towel rail begines to get hot.

This can happen if one of the two pipes to the radiator is blocked

There is an in pipe ("flow") and an out pipe ("Return")

If the rad squirts when you bleed it, (at least) one of the pipes is working. But if it doesn't get hot with water flowing through it, one of them might be blocked.

Try turning off the valves at each end of the rad (you may need a small spanner). Then bleed it again. If you have tightly closed both valves, no water should come out. Then open the valve at one end only, and try again. If water comes out forcefully, that pipe is not blocked. Then close that one again, and open the other. That will tell you if one of them is partially or fully blocked.

One possible cause is that one of the radiator valves might be closed, either because someone screwed it down in summer, or because it has a TRV which has jammed shut. You should check this.

If there is SOME water flowing through (the radiator gets partially warm) and you have a sediment blockage, the chemical can flow past the sediment and possibly soften it. If the pipe is completely blocked with sediment (no flow at all) the chemical can't flow down the pipe to get at the blockage and the blocked pipe may have to be cut out.

The relevance of a radiator which has been added later to an existing system is that it may have been added in a way which gives poor flow. This is quite common.

The relevance of a "high" radiator is that if the system is short of water, the water level may not reach the highest point.

If you have a Combi boiler, this will be a sealed system, with no Feed and Expansion tank in the loft. In this case, any water that you bleed out will lower the pressure in the system, and you will have to top it up with the flexible water pipe by the boiler. Have you noticed the Pressure gauge at the boiler dropping while you have been bleeding, and have you topped it up?

 

[lostmystickinsect]

Have you noticed the Pressure gauge at the boiler dropping while you have been bleeding, and have you topped it up?

I do have a combi system and the pressure has gone down each time I have bled the radiator. I keep topping it up as required.

I'm gonna have a look at the return valve tonight. Thanks again.

 

[lostmystickinsect]

Wowee - it's working!!

Looks like it was a valve problem after all. Over the weekend I investigated the valve a bit further. I took off the victorian-style crosshead tap, took the spindle(?), poked the valve thing a few times, unscrewed a nut, got a bit wet, screwed it all back together and hey presto it works. Half a rubber seal fell out somewhere along the line, and there is now the tiniest drip from the valve - but I can live with it!
Yippee - nice warm towels and cosy bathroom. Thanks for all your help!
Amanda

 

[Vurey]

I know it's an old topic, but I just wanted to say that I was having the exact same problems with a similar towel rail in my house. After reading through the advice, I worked out that there was a blockage in the left valve.

I started dismantling it (forgetting to switch the water off!) and some black sludge shot out (along with quite a bit of water). After quickly putting the valve back together and repressurising the boiler, it was working again!

I like to think I'm a bit handy with joinery and tiling, but plumbing is like voodoo to me. Thanks to this message board, I managed to avoid calling out a plumber. Thanks for saving me a few quid!