Cold radiator

[keyboardangst]

I've tried not to waste people's time by reading the FAQs on radiators etc but here I am starting a thread anyway.

I have a nearly cold radiator at the top of the house. Bleeding makes no difference. From archived threads on this forum it is suggested that you turn all the other radiators off and put the heating on. What happened then was the heating came through pretty well into the radiator in question.

Is this turning the other radiators off supposed to be a possible cure or just a way of finding out what the problem is?

When I put the other radiators back on, the radiator in question went back to being almost cold. The pipes in and out of this radiator are hot though.

 

[Bahco]

Balance your system as per FAQS.

 

[JohnD]

read the FAQ on balancing. If you reduce the flow through the other rads more will go through this one.

If it used to be OK and is now poor flow, you may have a buildup of sludge, or a worn-out pump, or maybe (if you have a 3-port vave) too much heat is going to the cylinder.

If you suspect sludge, a chemical clean done soon may do the trick. Waiting until you have an actual blockage makes the job a lot harder and more expensive.

edited: bah. too slow

 

[keyboardangst]

Balance your system as per FAQS.

If the pipe going in and out of the coolish radiator is hot why should the system need balancing? It's not as if the hot water has failed to get up to this top floor radiator. It just isn't getting into the radiator.

Is that a dumb observation on my part? If so, please can you tell me why?

 

[Bahco]

Must be TRV or valve problem then.

FAQs

 

[JohnD]

Bleeding makes no difference.

so when you bleed it, does water squirt out forcefully? What colour is it? do you get any air out? How high is this top radiator compared to your feed and expansion tank?

Just to check- did you balance the system? And did this help?

 

[keyboardangst]

Bleeding makes no difference.

so when you bleed it, does water squirt out forcefully? What colour is it? do you get any air out? How high is this top radiator compared to your feed and expansion tank?

Just to check- did you balance the system? And did this help?

The water shoots out forcefully. It looks pretty clean. No air. The coldish radiator is the floor below the feed and expansion tank.

On balancing. I haven't learnt how to reduce the flow on those of my radiators that have thermostat valves. More studying required.

I should have said though that my top radiator is just the highest one I use. I have 3 more up in the attic that are always turned off except occasionally during a very cold spell. The last time they were used - last winter - they worked so long as I bled them on a virtual daily basis.