Question about fitting a new cold water tank in attic

cojomo2

Hi,

Fitting a new headder tank in the attic. Is it safe to assume the existing copper pipes are imperial size (fitted about 30 years ago)?

If so I need to drill holes in the tank for 1/2" and 3/4" compression tank fittings. Question is, what size holes should I be drilling for each?

Cheers!

Tom44

3/4" hole for 1/2" tank connection
1" for 3/4" tank connection

Use washers

Perfebaly call plumber, to guarantee sealant.

cojomo2

Tom44 wrote: »

3/4" hole for 1/2" tank connection
1" for 3/4" tank connection

Use washers

Perfebaly call plumber, to guarantee sealant.

Thanks, rubber washer on the inside of the tank I assume? Or one each side? I have 16mm and 25mm holesaw bits, that sound ok? Cheers

Sleeper12

Make sure that it's sitting on plywood or similar. Old galvanised tank can sit on joists but plastic tank needs to be fully supported. They will bend out of shape if not supported correctly

cojomo2

Sleeper12 wrote: »

Make sure that it's sitting on plywood or similar. Old galvanised tank can sit on joists but plastic tank needs to be fully supported. They will bend out of shape if not supported correctly

Yeah thanks, I have a load of spare laminated chipboard, was planning on using that.