ON MY RAVENHEAT 820 RFS ?
STARTED LEAKING WATER, AFTER I HAD A LOOK FOUND IT WAS COMING FROM THE TOP OF THE UNIT, THERE WAS A SMALL PLASTIC CAP LYING BESIDE,LIKE A TYRE VALVE SO I SCREWED IT BACK ON THE LEAK HAS STOPED, HAVE I DONE THE RIGHT THING ,WHAT DOSE THIS ITEM ACTUALY DO?
DAVID, April 2009