How can I tell what's wrong with one single radiator that won't heat up?

Question

All the rest of the radiators are working well but this one. I tried bleeding it but to no avail. The tubes leading to it get very hot, but the radiator itself remains cold.

Answer 1

The regulator on the side might be faulty, take the plastic cap off and try using a spanner or wrench to turn the adjuster.

Answer 2

The fact that you say the tubes (plural) get hot would indicate that the pipes both enter the radiator at one end through a twin entry Yorkshire valve. If so then the insert has come out of the valve. This was usually a nylon 8mm tube about 9 " long and screwed into the valve, you could use copper but try not to let the pipe touch the inside of the radiator as this could start corrosion through electrolysis. Some other makes of twin entry valves had 10 mm inserts.

Answer 3

You have an air lock in this radiator. GGet a spanner large enough to undo the nut at the top of the rad, opposite the air vent.Slowly undo this nut until water starts to trickle out . make sure you have something to catch the water in. Let the water trickle out until you feel the heat coming from the bottom of the rad. Wheen the heat eventually reaches the top of the rad, tighten the nut and it should be okay.

Answer 4

It may still be an air block at the top of the house. I have had a similar situation, and found the only way to clear it was to bleed all the upstairs radiators. I know it sounds strange but it worked for me.

Answer 5

Replace the complete central heating system! It's probably the valve but may be ferred up like a kettle with calcium in which case the rest of the system is likely to be as well. Bad news. Commiserations

Answer 6

if the lines leading to it are getting hot, then some heat is getting through, but it probably has a restriction to the flow and distribution of even heat. Flush the radiator through, it's clogged with rust and mud.

Answer 7

If you have alreqady bled the air out and this is NOT the problem then I would say that you have a blocked lined. There is some build up of some sludge or something in the water line. Time to call a plumber.

Answer 8

need to bleed the line should be bleeder valve on radiator open valve put small can under to catch water bleed until all air is gone

Answer 9

It sounds to me like your radiator is blocked, it would have help me more if you had told me, when you tried to bleed it did air come out, or water, or nothing at all, of nothing at all, it is blocked and will need either descaling, or replacing, don't worry its not that difficult, hope that helps :¬)

Answer 10

sounds like a thermostat problem, if its not a blockage, I think it is a fault on the thermostat. I work for a property maintenance company and its a persistant problem with the valve on the rad itself.