CH drain point and Individual radiator drain points

[Cha0s]

Having whole house refurb and extension part of which is a complete new CH system.
(its a bungalow)

Having read around the forums and and net I think I want :

1) drain points on all radiators (the lock-shield with built in drain off) so that radiators can be removed for decorating etc.

2) a system drain off that's located outside the house, i.e. through the outside wall the boiler will be hung on.

The drain points on all radiators looks to be double the price (from screw-fix and the like). were talking something like 10 rads, an extra £2.50 each.. doesn't seem like a massive cost to me.
I doubt the plumbers / builder will have specified this as standard.

The only thing I'd be worried about with the outside drain point is it freezing in winter. but it could be protected fairly easily.

Can anyone in the know validate my thoughts. Cheers.

 

[Madrab]

Not sure it's worth the cost, just so it's easier to drain down the rads. With a few easy steps, draining down a rad is relatively easy. So it's up to you. I'm never sure about those rad drain offs tho, given the heat cycles they and their seals go through, they may or may not leak when used after being unused after a long time.

A primary drain point for the CH, to outside, is good practice and recommended. Just keep the valve inside with a tail of pipe to outside and you won't need to worry about freezing.

 

[JohnD]

I have a couple of rads that are fed from loops from the ceiling, so I fitted those valves with drain on them. A plumber snapped one of the square spindles, so maybe the quality is poor. It was only a few years old so no reason for it to be badly seized. If I fit a new one I might put silicon grease on the thread.

A full-bore valve will drain faster and I think is better for washing dirt out after a chemical clean. Probably an advantage to put them on the return which will be a bit cooler.

 

[Madrab]

A plumber snapped one of the square spindles, so maybe the quality is poor.

Regular temperature cycles can weld the jumper and washer onto the seat, I've yet to come across one that's worked flawlessly. Regular drain points can be just as bad where it's gets regular temperature cycles with long periods of non use.

 

[JohnD]

would a ball valve stand the heat?

this one says it can be used with steam

http://www.screwfix.com/p/pegler-ball-valve-red-22mm/45277

 

[Madrab]

Yeah wouldn't think there would be an issue.

 

[Cha0s]

well the plumbers flew through the job.
we have no drain off points on the rads but do have an outside system drain point.
I can add the rad drains later if needed.

thanks for the advice.