Small radiator not working

SimonG · Jan 19, 2020

Close off the towel rail as well. Shouldn't cause an issue with the boiler.

Can also disconnect flow and return to radiator and let it blast into a bucket.

doitmyself · Jan 20, 2020

Alastair1954 said:
With lock shield closed and TRV open, warmish water flows from the air vent. With lock shield open and TRV closed, similar result. With both valves open the flow from the vent increases significantly, but with the vent closed there does not seem to be any flow across the radiator. Gut instinct (and the flows mentioned above) leads me to suspect both flow and return are pressurised equally, so no differential pressure and thus no flow.

I assume the tests were done with the boiler not working so the pump was not running. In which case the test results are as expected. There will be very little difference in the pressure either side of a radiator when the system is not working. It's ony when the pump is running that you get any significant difference

Alastair1954 · Jan 20, 2020

doitmyself said:
I assume the tests were done with the boiler not working so the pump was not running. In which case the test results are as expected. There will be very little difference in the pressure either side of a radiator when the system is not working. It's ony when the pump is running that you get any significant difference

Actually, it was with the pump running. Looks likely that I have a blockage in the pipes or radiator. I will remove the radiator tomorrow and check the flow into a bucket as suggested by Simon. I will also take the opportunity to flush though the radiator. I’m hoping I’ll resolve or at least diagnose the issue tomorrow. Thanks.

centralheatking · Jan 20, 2020

JP1 said:
Problem found... the pipe work in the wall has a kink in it. When I take the rad off the wall and straighten the pipes up, it works perfectly!

Thank you to everyone that has helped. Really Appreciated. I am glad I didn't go with British Gas's advice of a Power Flush-£700!!!

British Gas what a sorry outfit they are now populated by sales orientated numpties no wonder Centrica are trying to sell the outfit off but no one wants it Centralheatking