Vokera Compact 28 leaks

[vokeraques]

Hi there,

I have a Vokera Compact 28 Combi Boiler. I recently drained the water from the boiler via a radiator, so I could remove one of the pipes from the heat exchanger. I cleaned the pipe to remove accumulated magnetite debris. I had cleaned the other pipe previously which was clogged with magnetite (on the second inspection, the pipe I had cleaned previously was still free of any debris). I also cleaned the heat exchanger, a lot of magnetite came out of it, and I cleaned it until seemed to be free of debris.

After, I put the pipe back on, and re-pressurised the system to 1 bar. I then started the combo boiler and it has been functioning well. However, I noticed that occasionally there is a very slight leak from the Automatic Air Vent - the little black cap that screws onto the (brass?) cylinder. Please see attached photo of this part. I wondering if this part has developed a fault when I repressurised the system? Or if I just need to perform some action to clear water from this part?

The steps I took were -

Drain combi boiler via radiator
Disconnect boiler from electric & mains water input
Remove pipe from heat exchanger, clean, put back in place
Reconnect mains water supply and electric
Repressurise combi to 1 bar using water inlet valves.

An additional existing fault for sometime now, is that one of the valves that is used to pressurise the system, leaks ever so slightly from what appears to be the black plastic part you turn. I think I need to replace this - but not sure what it is called? I have attached a photo of this part also.

Thanks for your help

 

[terryplumb]

The auto air vent will probably need to be replaced ,if its passing water. Not worth trying to repair IMO. The black handled valve is an isolating valve ,part of the filling loop. You can buy a new loop complete with iso valve for around ten quid.

 

[vokeraques]

Hi Terry,

Thanks for your reply. When replacing the air vent, do you know if the system needs drained / depressurised for that?

Thanks again!

 

[ianmcd]

just de-pressurise the boiler, these can be a real pain to replace though.

 

[vokeraques]

Thanks Ian, it looks the whole thing just screws off though? But it is awkward to get to by the looks of it..

 

[ianmcd]

just screw the cap down for now and it will stop leaking, it is a float operated valve that allows trapped air out but to be honest only really needed when you drain and re-fill the boiler , just screw the cap down with your fingers and it will stop leaking