I'm installing 2 new rads in the loft. I have pipe going from loft to the garage (pre installed when house was built) to above the baxi combi boiler.
Boiler has two out feeds, up stairs which I want to tap into, and another for downstairs. And one return. All are 22mm. All pipes come out of boiler the go vertical.
I need to (I think!) put a tee into the upstairs feed and a tee into the return. There are drain offs on both pipes just under the boiler.
My question is, if I freeze above where I want to make the cut and then open the drain offs, will that allow me to cut the pipe and do the work? Or will I get the full system emptying back through the boiler somehow?
Thanks in advance for your help!