Is this asking for trouble?

[PhilipKS]

Hi All,

I am going to fit a sink in the utility and take hot and cold feed from the supply to the washing machine.

Cold is easy as I’ll turn off the mains supply. Hot water (vented indirect system) is more tricky, as whenever I have drained down the system I end up with massive airlocks which take ages to fix and usually involve me having to strip the shower pump connections down…

The hot supply where I want to cut into it is 22mm so pipe freezing not ideal.

I have an idea that I might just saw through the hot pipe “live” and quickly fit a compression isolation valve. The utility has a quarry floor and flows of water could be easily directed outside, so mess issues not a problem.

Or pushfit…but might be harder against a head of water?

Or is this asking for trouble?

I also had an idea that (with the hot water turned off) if I shut the gate valve on the cold feed to the hot tank and temporarily bung the expansion vent pipe, with all other taps shut I will create an airlock that means I can cut into the pipe with less water loss? A bit like bunging a central heating system?

Or is there something blindingly obvious I’ve missed (probably!)

Thanks
Philip

 

[Agile]

If you turn off the cistern outlet gate valve only a very small amount of water will flow out of the hot tap in the kitchen thus allowing you to do the fit.

Use a pipe slice and NOT a hacksaw if you want to use pushfit.

Hacksaw is OK for compression but you should still file the cut edge.

Tony

 

[PhilipKS]

Many thanks - Worked a treat!