DIY Cold Water tank?

stator

Hi All,


My loft tank needs replacing. The ballcock valve is knackered and the whole thing is a bit manky so I've bought a new one with a push fit lid that should keep things nice and tidy.


Recently due to a leakage I replaced my central heating pump and valves, using a few guides on Youtube. It looked simple enough so I gave it a go and surprisingly it's all working perfectly :T


Is there any reason why I can't replace the cold water tank in the loft myself? The new tank will require some pipes moving and replaced, so it will involve new pieces of pipe and fittings.


Can compession fittings be used on the cold water supply to the loft? This is the only high pressure pipe, so is the one I'm worried about. The rest of the system is gravity fed.


All input gratefully received

chrisw

It's pretty straight forward. Just make sure its well supported on the rafters as it will be heavy when full.

You can use compression fittings or plastic push fit pipe and fittings is an easy option.

The difficult bit might be getting the tanks through the loft hatch.

stator

chrisw wrote: »

It's pretty straight forward. Just make sure its well supported on the rafters as it will be heavy when full.

You can use compression fittings or plastic push fit pipe and fittings is an easy option.

The difficult bit might be getting the tanks through the loft hatch.

Good to hear as I've already got the new one in the loft
Screwfix sell a nice one that fits through most hatches


Thanks

tacpot12

If you want to use push-fit fittings, use good ones like Tectite Pro and get the demounting tool.

stator

I was thinking brass compression fittings with the olive thingy rather than push fit. Is that ok?

chrisw

You can use compression fittings but plastic push fit is much quicker and easier.

FreeBear

Depending on how old the system is, you may well find the pipes are the old imperial size. Not a major issue with 15mm pipe (imperial - 1/2"), but 22mm pipe is slightly larger than the old 3/4" stuff. I'd recommend compression fittings and grab a couple of imperial size olives just in case - You can use 22mm compression fittings on 3/4" pipe with the right olives without any trouble.


Once you have the tank in place, don't forget to insulate the sides & top well and lag the pipes too.

MX5huggy

Make sure the overflow for the new tank is correctly installed and sized.

Walked past a friend’s house the other day the overflow was pouring out at full tilt, ballcock float had failed, they were away. The overflow was not keeping up with the water entering the tank, the water level was an inch above the overflow with about 2 to go before it overflowed the top of the tank.

stator

MX5huggy wrote: »

Make sure the overflow for the new tank is correctly installed and sized.

Walked past a friend’s house the other day the overflow was pouring out at full tilt, ballcock float had failed, they were away. The overflow was not keeping up with the water entering the tank, the water level was an inch above the overflow with about 2 to go before it overflowed the top of the tank.

Good point, mine is actually not able to cope with the mains on full. I know this because it overspilled a bit previously, even though water was pouring out the overflow. I think it might be impossible for it to cope with the full mains pressure through an overflow, which is gravity fed.


Might be a good idea to fit a tap, so the pressure can be reduced before it goes into the tank? There is a tap before it gets to the loft, but keeping this on half way would stop water getting to the heating header tank, which is much higher and so needs the higher pressure

MX5huggy

There’s no reason not to fit 32mm or even 40 mm solvent weld waste pipe. Would have to drill a larger outlet.

stator

The problem is that the pipe goes into the eaves and out through the fascia board, which is pretty inaccessible to make the hole larger