Poly tank life

[YorkshireMidge]

I've had to remove what turned out to be two linked c15 gallon cold tanks in an airing cupboard, to fix a broken gate valve on the gravity fed hot right at the very back.

The tanks have obviously not been disturbed since the flat was built around 30 years ago, and there is no cover on either, and they are pretty horrible inside. I'm sure they would respond OK to a good pressure washing now they are out, but I wondered if there was guidance on the life of such tanks?

I think they went this route due to the limited height available between tank and ceiling, but I have found a 30G tank which is the same 17inch height, so I'm minded to change it and sort the pipework out to make it easier to maintain in the future.

Also, I'm thinking of replacing the hot cylinder as its certainly an old looking thing, but it's an E7 dual immersion heater type. Any recommendations on manufacture as these seem to be more difficult to find?


Thanks.

 

[alan999]

I've always thought anything made of heavy duty plastic will be around long after I've gone though I'm getting on a bit now. Check the tanks aren't stretched and were well supported.
You cannot just change a hot cylinder any more. You have to be qualified and the new cylinder needs a certificate.

 

[REEMS]

You dont need to be qualified to fit an open vented cylinder you need to be G3 certified to install an unvented, if you are changing the cold water tank, which i would it must comply with bylaw 30 for the storage of cold water which should be stamped on it, also when you replace the cylinder make sure you replace the emmersion elements to new ones that have the overheat safety cut out.

 

[oilboffin]

If you need to know regs go online or phone building control offices and there is cylinder cert you need to fill in and of course you have to fit a valve on the hw inlet to the cylinder.Bob

 

[YorkshireMidge]

You dont need to be qualified to fit an open vented cylinder you need to be G3 certified to install an unvented, if you are changing the cold water tank, which i would it must comply with bylaw 30 for the storage of cold water which should be stamped on it, also when you replace the cylinder make sure you replace the emmersion elements to new ones that have the overheat safety cut out.

I mulled over unvented on an earlier thread but it turned out it would be very difficult and expensive to comply with the regs for the safety outlet due to where the cylinder is.

I'd planned to replace the immersion elements as a matter of course as they look as old as the tank! On the E7 tank, I have found its possible to get a dual element immersion heater for E7, so just weighing up whether its cheaper to buy one of those over an E7 tank and two separate immersion heaters.

Thanks for the pointer on bylaw 30 - it looks like the tanks I've seen can be supplied with a bylaw 30 kit.

 

[YorkshireMidge]

I've always thought anything made of heavy duty plastic will be around long after I've gone though I'm getting on a bit now. Check the tanks aren't stretched and were well supported.
You cannot just change a hot cylinder any more. You have to be qualified and the new cylinder needs a certificate.

The tanks were supported OK, and the only thing I noticed was a very slight outward bulge around the outlets, and bit of distortion around the ball valve due to lack of backing plate. I think on balance, I'm now edging towards replacing it with one single new tank.

 

[YorkshireMidge]

If you need to know regs go online or phone building control offices and there is cylinder cert you need to fill in and of course you have to fit a valve on the hw inlet to the cylinder.Bob

Take it you mean the gate valve which has failed must be retained? Yes - I plan to stick a quarter-turn pegler lever valve in place of the cheap rubbish gate valve that broke.