Last week I fitted an external expansion vessel to my Vaillant CH system. While I was there, I flushed and re-inhibited the system.
Having been bitten before, I pressurised the system initially with just water - fired up - no leaks. Great.
Added flush, ran system for a couple of hours. Fine.
Drained, added inhibitor. Refilled and (you can guess this bit) the AAV on the pump started ****ing water.
A speed-Google later, I removed the valve, cleaned it, refitted, and so far (4 days in) no leak, no pressure loss.
When I located the leaking AAV, the plastic cap covering the spout was hardened and cracked off.
Now my pump (clearly labelled as a Grundfos 161015) is a Vaillant VP5/2. The AAV is a metal cap which screws onto the plastic body of the pump (as shown).
However, a search of Vaillant suppliers - including Vaillant - keeps returning something which isn't that, but a complete brass body which screws into something.
The boiler was fitted in March 2002 (!!!) and has this on the inside:
TURBOmax VUW GB 242/2-5
TURBOmax Plus 824 E
Is this a case of I need to buy the complete brass assembly, but just use the screw on cap ?
Having been bitten before, I pressurised the system initially with just water - fired up - no leaks. Great.
Added flush, ran system for a couple of hours. Fine.
Drained, added inhibitor. Refilled and (you can guess this bit) the AAV on the pump started ****ing water.
A speed-Google later, I removed the valve, cleaned it, refitted, and so far (4 days in) no leak, no pressure loss.
When I located the leaking AAV, the plastic cap covering the spout was hardened and cracked off.
Now my pump (clearly labelled as a Grundfos 161015) is a Vaillant VP5/2. The AAV is a metal cap which screws onto the plastic body of the pump (as shown).
However, a search of Vaillant suppliers - including Vaillant - keeps returning something which isn't that, but a complete brass body which screws into something.
The boiler was fitted in March 2002 (!!!) and has this on the inside:
TURBOmax VUW GB 242/2-5
TURBOmax Plus 824 E
Is this a case of I need to buy the complete brass assembly, but just use the screw on cap ?