Isar HE30 air vent valve leak

[radio_engineer]

Hi,

I have identified that air vent valve on ISAR HE 30 is leaking and as a result system pressure is low. Boiler still works but the CH system pressure is only 0.3 bar when hot. If the system pressure is raised air vent valve leaks out and then the leak stops at arround 0.3 bar.

I have new air vent valve but the problem for me is that the location of the valve is at the back of boiler and impossible to reach to change the valve.

Can this be done without removing combustion parts ?

Is there any alternative fix?

 

[radio_engineer]

Hi, has anyone seen this problem before with ISAR ?

 

[shapes01]

Yes I have, Is the Boiler under a year old?

 

[Garfeild]

You have to remove the fan and burner,even then its not easy,use a pair of grips to remove it,and refit the new one,i made a special tool,cos i was changing them all the time, a sort of socket that fitted on the AAV perfectly,that made it easy.

 

[radio_engineer]

Yes I have, Is the Boiler under a year old?

Boiler is just over 2 years old, fitted by BG, out of warranty

 

[radio_engineer]

You have to remove the fan and burner,even then its not easy,use a pair of grips to remove it,and refit the new one,i made a special tool,cos i was changing them all the time, a sort of socket that fitted on the AAV perfectly,that made it easy.

Thanks

is AAV pushfit or treaded ? it's difficult to see.

I was looking for a way to do this simply, unfortunately it will probably be job for pro.

Thanks for the advice

 

[Garfeild]

Its threaded,use a bit of grease to lube the new one as it has an o ring to effect a seal,it will leak if you dont wind it right in.

 

[45yearsagasman]

This is a simple change,but is Pro work. Case front,fan(which means disc a gas union) is best removed b4 you can easily access the auto air vent