Hi all
This is a major pain in the proverbial! About 3 years ago, I spent the best part of a day fitting an Essex flange to our hot water cylinder - not a job I want to repeat in a hurry. The understanding was that this would resolve a cavitation/pump problem with an Aqualisa shower. Not only did it not cure the problem, but, last Friday, I returned from a week away to find a puddle in the airing cupboard :(.
Being the cautious chap I am, I had turned off the hot water program, so that the cylinder cooled completely during the course of the week. This has created a leak which is not evident when the tank is up-to-temperature. The rate of leak was about one drip every 5 seconds. It doesn't sound like much, but over a week it was enough to soak the floor and scrap of carpet in front of the cylinder. I believe that the leak has been occurring intermittently (ie when the tank is emptied of hot water in use), but that the quick heat up soon after has sealed the leak and evaporated any escaped water.
Examining the leak source showed the water to be appearing from between the outside fixing nut and the plain washer behind. This suggests to me that the seal between the split-washer-inside-the-tank and the inner tank wall has failed allowing water to track along the threads as far as the outer nut.
Does anyone have experience of these fittings to know whether this is a usual failure - maybe down to hardening/perishing of the inner washer in the hot water (obviously they should be fit for purpose but who knows?). What material should these washers be made of to withstand the conditions? Also, from memory, it was a fiddly job assembling this lot. How replacable are the rubber(?) washers, particularly the inner one?
TIA
Phil