Advice please soldering to old pipe

TB204 · Sep 12, 2016

I've added a couple of additional rad's to a room at he back of my house (all within the boiler capacity) and I'm in the process of upgrading feed and returns from 15mm to 22mm to cope with the extra demand.

The pipe work is ok except where I'm joining to the existing old pipe. I'm using capillary slip fittings as there is insufficient lateral movement to use a straight connector. However, I'm struggling like hell to get a leak free joint. The pipe seems slightly loose on the fitting and I'm not getting a decent capillary joint. Its not a huge amount smaller - probably 0.25 mm, but seems enough to prevent a good joint. I'd appreciate any advice anyone. I'm on my third attempt.

Alternatively, I'm thinking I might have to use compression although as its under floor boards I'd rather not.

Hope someone can help.

Terry

Chalked · Sep 12, 2016

Was the sysem installed before 1975 ish? If so will be imperial copper 3/4. You can get solder ring, or end feed fittings fir this. Normally called 1m's ( imperial to metric) adaptors.
Most will pact as a slip coupling too, as the fitting will slide fully onto the old copper.

TB204 · Sep 12, 2016

Thanks for the reply.

Not sure when it was installed - but I suspect it was later. I think I might be being a bit daft. I was thinking that 3/4 pipe was the outside diameter of the pipe (as is the case with 22mm) which is why I thought 3/4 would be too small. But I guess 3/4 is the bore in which case I think you've sussed it.

Thanks,

Terry

ShaunCorbs · Sep 12, 2016

as above is coupling is loose is eg can wiggle its 3/4 pipe

http://www.NoLinkingToThis/p/solder-ring-imperial-metric-adaptors-22mm-x-2-pack/74038

TB204 · Sep 12, 2016

Thanks Shaun.

Terry

Best · Sep 12, 2016

Imperial pipe was around to about 1973 I think.
One tip if using a 3/4" x 22 solder connector is that they usually will act as a slip connector on the 3/4" side because the 22mm end is bigger. Be careful to push the fitting full back onto the 22mm pipe until it hits hard.