Central heating intermittent, auto air vent valve leaking.

[Pooly]

I have a Ravenheat RSF82ET, I recently had a problem with the domestic hot water which I resolved by replacing the diaphragm and microswitch on the diverter valve. The hot water is working perfectly but I now seem to have trouble with the central heating. The boiler fires up and runs OK till the central heating gets up to temperature/pressure and then turns off. When it fires back up again it only runs for about a minute and then turns off again. Also I have noticed that there is water coming out of the auto air vent valve. Do you think I may trapped air in the system?

 

[chrishutt]

Sounds like you might. But if the AAV is leaking water you know you haven't got air trapped there. Does any circulation take place through the heating flow pipe? Have you left any isolating valves closed?

 

[Pooly]

The isolation valves for the central heating are both open and the water is flowing around the system. What does the leaking water from the auto air vent valve mean? Does it need replacing.

 

[chrishutt]

Replacing or cleaning.

If the water is circulating normally around the system and the boiler goes off when it gets up to temperature then it sounds as if it's operating normally. What is actually the problem?

 

[Pooly]

The problem is when it fires back up again it only stays on for about a minute and then shuts down.

 

[chrishutt]

So? Why is that a problem?

 

[Pooly]

I just don't remember it being like that before.

Do you think it's working fine apart from the leaking vent valve.