How to repair duff Air release valve? Drain or not?

[edscratcher]

Any advice please?

The COMAP air release valve in the photo has been leaking from the top. It used to hiss from time to time but no more. Can it be serviced or replaced without partially draining the system if I shut that gate valve on the cylinder outflow pipe and set the system so the motorised valve is in Radiators Only mode? Or is there a better course of action?

Thanks in advance.

 

[shambolic]

That would work no problem set mv to ch only and shut off hw balancing valve!

 

[gas_man_gaz]

it might work.. but id turn the power off, bung it n fit a new1

 

[edscratcher]

it might work.. but id turn the power off, bung it n fit a new1

Does 'bung it' mean freeze the pipe on the motorized valve side?

 

[gas_man_gaz]

no, it means block the cold feed and the open vent with rubber bungs..
doing this will create a air lock and only allow a small amount of water out, id still shut the gate valve on the return from the cylinder tho

 

[shambolic]

BUt turning the cylinder valve off and the zone valve to heating and killing power will also work(provided valve is closing ok.
I would try that first and if it doesnt work then bung it.

Personally I would go with first option and then snatch it!

 

[shambolic]

no, it means block the cold feed and the open vent with rubber bungs..
doing this will create a air lock and only allow a small amount of water out, id still shut the gate valve on the return from the cylinder tho

Provided you open the drain first to remove some water creating the vacuum!
Then close drain before you attempt to change AAV

 

[gas_man_gaz]

 

[edscratcher]

Personally I would go with first option and then snatch it!

I understand 'bung it' now - What does 'snatch it' mean?

 

[gas_man_gaz]

do it quick!

 

[edscratcher]

do it quick!

I was afraid that's what it meant

 

[shambolic]

do it quick!

I was afraid that's what it meant

You should not have any pressure there though if both valves are shut!
The snatch bit is a just in case

 

[Boilerman2]

I trhink the Comap AAV has a Quick release fitting that shuts off the water as the valve is removed, (make sure you leave the Hexagon part in the pipe) use a spanner to hold it back, whilst unwinding the AAV body with a pair of pump pliers, fingerscroosed the fitting will seal, but as been said with the return valve shut and the mid pos on CH only you should be ok

 

[edscratcher]

I trhink the Comap AAV has a Quick release fitting that shuts off the water as the valve is removed, (make sure you leave the Hexagon part in the pipe) use a spanner to hold it back, whilst unwinding the AAV body with a pair of pump pliers, fingerscroosed the fitting will seal, but as been said with the return valve shut and the mid pos on CH only you should be ok

Is this the type you're thinking of? Does the circular 'lid' come off?