Problems with pipes - pressure release valve?

oojeyboojey

My hot water tank was not properly maintained by the previous owners of my house, and I foolishly didn't bother to thoroughly check it over when I moved in (over a year ago - shame on me!)

It's been working fine up until this weekend, when I noticed the top-most piece of pipe in the picture was leaking. On closer inspection (I have no experience with plumbing so I might be wrong...) it appears to be a pressure release valve. I took the insulation off the tank to find that the thermostat (Honeywell stat L641A1005) was no longer in contact with the tank - the strip of metal that was used to strap it was rusted through. Also, it looks like the hot water pipe coming into the tank has a dodgy weld - there's corrosion around the joint, which explains why the metal strip rusted away.

So I think the joint started leaking, caused the metal strip to rust through, which made the stat lose contact with the tank, which meant the hot water was being heated too much, which caused the valve to start leaking. So, I've re-attached the stat to the tank and turned the temp setting down to 50degrees, but the valve is still leaking (I've been catching about 500mL of yellow waterin my little bucket every 5 hours or so - more when the heating/hot water is on).

I'm going to call a plumber in but would like to know how much you guys think this might cost to fix, and what the worst case scenario is! Any advice you can offer would be appreciated since I'm a novice in this area.

ariba10

It looks like an automatic air vent to me. If it is, it would just need the system drained down and a new one fitted. (Nothing last forever)

ormus

also looks like a bottle air vent to me.
about 5 quid each and about ten minutes to change.

plumb1_2

Personaly i would replace it with a manual air-vent(1/2" rad vent)
And set your cylinder stat @ 65c

capita_guy

ormus wrote: »

also looks like a bottle air vent to me.
about 5 quid each and about ten minutes to change.

So tell me how you drain down and refill a system in 10 minutes?

oojeyboojey

Thanks guys! I got a heating engineer neighbour to have a look and he confirmed your suspicions. He's going to help us replace it, and sort out the dodgy seals. Huzzah!

EliteHeat

capita_guy wrote: »

So tell me how you drain down and refill a system in 10 minutes?

Ormus is special. He can do things no ordinary person can.