Leaking cold water tank

Cracks can spread. I'd be inclined to bolt a small metal angle across the outside of the tank to support it and hopefully prevent the crack spreading down the corner. Also, drill a small hole (3/8 inch, say) through the tank at the end of the crack to stop it going any further.

Then an application of silicone sealant (on the inside) should do it. You might have to keep the water level below where the hole is until the sealant has cured, or the water might push it through the hole.

Rob Graham

There is a repair kit available in B&Q for this. About a fiver. Just have a look down the plumbing aisle.

Adam

Thanks for the help guys - appreciated! Dennis

Hi Burbeck Thanks. I would like to replace the tank, but the loft opening and the angle/positioning of the roof spars means that I could only get a small cistern in. Bit reluctant to fit a small unit as I fitted a power shower and water softener last year, with the result that the tank empties quickly and fills slowly. The current tank is quite large and must have been put in place before the roof was put on.

Fortunately I seem to have fixed the leak (with Loctite Super Steel), so touch wood, I wont have to do anything else, apart from checking it say once a month. There was only a tiny droplet of water seeping out of the tiny short crack, but it still managed to make a hell of a mess.

Cheers Dennis

Change the tank now. I had this type of problem, drilled two holes at end of crack, filled holes with stainless bolts and washer and silicone, but just leaked again albeit a year or two later.

I replaced the one large tank with two smaller tanks, that were easy to get througth the loft hatch joined jogether with two short lengths of 22mm pipe and tank connectors,

Acord>> hi Dennis,

It'll work fine, but the water in the second tank is likely to become stagnant. A great place for our favourite Legionella to have time to grow!

Andy

Not in the cold tank ??

I though water had to be stationary and above 30°C for a long time for this to happen.

"Whilst Legionella pneumophila has been isolated from water at temperatures ranging between 7 - 58 °C, the bacteria only multiply actively between 20 to 45 °C. A minimum temperature of 60 °C is required to kill Legionella bacteria in hot water systems (the higher the temperature the shorter the required contact time)"

I think the water in the 2nd tank could get to over 20 in the summer. There are stories of problems when people return from holiday, and there's been no turnover in the tanks, there's a problem. Besides, there are plenty of unpleasant if not dangerous things that could grow there.

I think Legionella is overrated - but there's no point in taking a risk without a reason.

Andy