CH System faulty after drain down (Open Vent)

[Karl50uk10]

OK Terry. I tried with a magnet to no avail. I tried the air release valve already and nothing is coming out. Same with the pump. Not air or water on both.

I'll try and run the magnet on the piping in the loft tomorrow. shattered now !

 

[terryplumb]

Definitely blocked with something ,possibly non magnetic.

 

[Mottie]

I might be talking out of my arse here but when I had an open vent system and when filling it, the water wasn’t going in from the expansion tank due to an airlock, a plumber mate showed me a trick. He got about 2ft of hose pipe, stuck one end in the system feed pipe and gave one long massive blow in the other end and you would hear a rushing gurgle and that was it, airlock cleared and system then filled up. I did it several times myself afterwards. It might work for you maybe.

 

[HERTS P&D]

With the system turned on, Jiggle the pump speed up and down, this normally pushes the air around.

Andy

 

[Karl50uk10]

I might be talking out of my arse here but when I had an open vent system and when filling it, the water wasn’t going in from the expansion tank due to an airlock, a plumber mate showed me a trick. He got about 2ft of hose pipe, stuck one end in the system feed pipe and gave one long massive blow in the other end and you would hear a rushing gurgle and that was it, airlock cleared and system then filled up. I did it several times myself afterwards. It might work for you maybe.

Thanks Mottie. What do you mean by system feed? Cold feed pipe from the Feed tank?

Just ordered some Fernox F3 so will stick that in the tank tomorrow.

 

[Karl50uk10]

With the system turned on, Jiggle the pump speed up and down, this normally pushes the air around.

Andy

Thanks Andy. Tried that to no avail. No water in the pump to start with

 

[HERTS P&D]

Drain it down again and refill.

Refill it from the drain cock using your garden hose pipe.

Andy

 

[terryplumb]

There is no point putting chemicals into the system whilst you have no circulation ,it's totally pointless.

 

[Karl50uk10]

Drain it down again and refill.

Refill it from the drain cock using your garden hose pipe.

Andy

Is that pretty straightforward back filling Andy?

I guess if I drain it off and the feed tank doesn't drain that answers one question.

 

[HERTS P&D]

Or just connect your hose pipe to the drain cock, open the drain cock and turn on the garden hose. Latch open both valves in the air-in cupboard, go in the loft and watch the air come out.

Make sure all air bleed valves on the radiators are closed.

Once the water starts to rise in the expansion tank, go and turn off the garden hose and close the drain cock and turn the system back on.

Andy

 

[Mottie]

What do you mean by system feed? Cold feed pipe from the Feed tank?

Yes, the system feed pipe in the bottom of the expansion tank.

 

[MeldrewsMate]

Or just connect your hose pipe to the drain cock, open the drain cock and turn on the garden hose. Latch open both valves in the air-in cupboard, go in the loft and watch the air come out.

Make sure all air bleed valves on the radiators are closed.

Once the water starts to rise in the expansion tank, go and turn off the garden hose and close the drain cock and turn the system back on.

...and if it doesn't, make sure your garden hose is securely attached to that drain cock!!!

@terryplumb has given you some good advice - follow it.