Hi,
I bought a 220ml can of pipe freezing spray from tool station:
The can says you need to use one small can to freeze a 15mm pipe and two small cans for a 22mm pipe.
They also sell a big can. I was wondering: one big can is cheaper than two little cans; is there a clever way to use half the big can at a time? If working on CH you might need to freeze two pipes: flow and return. How could you estimate when you had used half the can on one and use the remaining half on the other? Or is it just best to pay the extra and buy two little cans?
Tool station are usually excellent on price but I think they are not the best price for these. I see other places selling "freezer spray" but some of it is advertised as for cooling electronics. Is it the same stuff or must you buy the plumbing type for plumbing jobs?
TIA
*In anticipation of the post about inhibitor, I realise you would want to replace it with fresh every couple of years anyway.