Draining Combi Boiler hot water

[meddyliol]

I expect this has been asked before but I really need to know how to do it. The problem is, my son is having a new kitchen put in on the first floor (UK) and all the water etc has already been installed and there are hot and cold water speed fit pipes coming out of the wall with the shutoff valves already fitted. Anyway, the pipes are too long and need to be shortened. I expect that if I shut off the cold water coming into the house then the cold water could be drained off by opening the taps. What about the hot water though? How do I drain the hot water before cutting the pipes. Another thing, the plumber who installed the supply didn't make a note of which ones are hot and cold, one is longer than the other so would that be the hot?
Sorry for a long blurb but if anyone can help it would be appreciated.

Thanks

Brian

 

[meddyliol]

Sorry but I shouldn't have asked the question. Must be too obvious.

 

[Ian]

It depends on how your hot water is pressurised, but if you turn off the cold mains and turn the boilers off, it's likely that you can remove the pressure from your hot water side too. If you've got a hot water cylinder, you may have a gate valve to shut off the flow from this.

You can drain it down using nearby taps, then take off anything remaining in a bucket from the speedfit shutoff valves you're trying to shorten. Once the flow stops, cut them to the right length .

 

[meddyliol]

Lovely jubly, I suspected as much. I have a combo boiler so cutting off the water in the kitchen, turn the boiler off. There's enough length on the speedfit pipes to enable me to open the valves to drain the water. Bob's your uncle and Fannie's your aunt. (Never really understood what that means ).

Thanks for your reply

Brian