Bubbling in f&e tank after refill

[Jmt15]

One of our upstairs rads was not heating up..drips of cold water on bleeding.

I thought this maybe due to a blockage somewhere, anyhow we opened the diverter valves and drained down the system.

We added fernox cleaner and refilled. All rads got hot apart from the problem one, ( I am hoping the fernox sorts this in the next fed days)

Also another upstairs rad would not vent on refilling although it's working fine.

Anyhow when we tested the hot water there was a bubbling in the f/e and the boiler turning off, I put the diverter to manual, this I'm sure put water in the system. I tried the hot water again and the boiler stayed on but there is still some bubbing and you can hear water moving a lot.


I wonder if the boiler is turning off because there is hot water left in the tank. My hope is this will clear itself.

I will try it later went the stored hot water has been used.

I would be very grateful of any help thanks

 

[hanns21]

The bubbling is air in the system because you drained down. You have air in the coil of your hot water cylinder.it might clear itself it might not as for your rad not working try turn all other rads off and see if it heats. Failing that it might be a faulty rad valve or again air. Take the rad off and other both valves into a bucket.

 

[Jmt15]

Hot water now fine...no air in coil thanks.

Shall take your advice on problem radiator..if no joy have to sort it when I drain down to flush out cleaner.

Thanks for your help