Service valves

[PLUMBBUDDY]

Hi all, Im moving a towel rail in the bath room, and also running another radiator off it. It looks like the towel rail was fitted after the C/H system because the pipes come from the boiler upto the tank and they (who ever THEY are), fitted this rail to these pipes. The problem i have is the pipes drop down from where there fitted to the main system, so when i drain the water im still going to have water in this part. is it worth fitting service valves to this so i can just drain this part down if i need. The new radiator is lower than the towel rail so i can drain it off from there. Are you able to fit service valves here? (in the C/H)? Or is it not worth the bother.
Thanx.

 

[kevplumb]

use gate or full bore ball valves

 

[PLUMBBUDDY]

Thanks,
Is that because service vales are not really made for C/H systems?

Tink i'll get some today.

 

[kevplumb]

what are normally reffered to as service valves restrict the flow to much look in the end of one

 

[ChrisR]

If you think microbore for a mo, 8mm pipe is enough for a radiator so I doubt any isolator would be too small for a single rad/towel rail. But the 35p variety isolating valves will only work for a short while before they start leaking through the shaft very slowly. The slightly bigger ones usually refered to as "heavy pattern" are definitely better, but FFBV's are best as they have something to do up to help seal the centre shaft.

 

[kevplumb]

8 mm is enough for a rad spheres it depends on the size of the rad

 

[blahblah]

I know you're talking about isolation valves but I've never fathomed the point of service valves that undo into two bits. Anyone care to enlighten me? (Dull I know, but I've got 15mins before the baby's bottles are cool enogh to go in the fridge).

 

[ChrisR]

"service valves that undo into two bits"

EH? The only ones I can think of which do that are gas isolators on old style boilers.

 

[kevplumb]

never come across them post a pic

 

[blahblah]

I had some service valves that I'd bought from screwfix about four years ago on the van. Was working on a loo (as a favour cos I don't do loos) and needed to change one. When I tried doing the thing up the bugger opened in two. The connection end was threaded with an o ring and came apart from the valve end. Didn't have a clue it was made like that until it kept leaking! Was a pain cos it kept undoing itself. Cursed, fiddled and cursed a few more times before gettting it to stay done up. Wondered why it was made like that and couldn't work it out- still can't. It wasn't my imagination, honest!

 

[kevplumb]

ahhh ive seen lever op f/f valves like that