How to operate a draincock

[Jan Larsen]

Hello

This may seem like rather daft question but how on earth does one indeed operate this device?

Similar in appearance to

tried to turn the square bit, nothing, then turned the collar thing underneath the square bit, got a bit of a dribble but not much, after a few more turns I noticed water emerging from underneath the collar and in fear of water emerging at considerable speed in directions other than my original intention and the swift administration of the mother of all bollockings by the wife I decided it best to turn the collar the other way and ask first.

I can only assume something needs to be attached to it.

I have looked in the FAQ and googled myself dizzy but seems unable to find any resources describing the correct operation of this mind boggling device.

//J

[Weatherlawyer]

A sponge or rag held up to it will protect the wall and carpet if you are just bleeding a radiator vent. Leave the spanner on the screw so you can close it without removing the rag, when water starts to come through.

IIRC you need to turn the pump off to do this. Or was it have the pump running. You get two choices.

If you are draining a radiator or something you obviously need to get a vessel under it. You might get a length of piping from a plumbers supplier or even a caravan shop or some such.

[Jan Larsen]

I want to drain the system completely.

I have a hose attached to the thing but no water comes out of it, just a slight trickle. the system is open vented so it should not be retaining a vacuum.

[Lobster]

You're doing it right; there's nothing particularly complicated about it. Presumably yours is jammed internally or something. You certainly shouldn't need to undo the knurled collar.

David

[John Stumbles]

Quite often the washer sticks to the seat of the valve so no water comes out until you open the valve quite a long way, or worse still it comes off the little peg that's supposed to hold it onto the moving jumper (which you're unscrewing) or simply disintegrates, so you can neither get water to drain freely nor shut the damn thing off fully again.

[Nick]

I would expect that the rubber washer has partially decomposed and is stuck in place. There is no completely mess free alternative way - what I try to do is get an identical looking drain valve and take apart to understand what gets stuck, get one or two similar washers as spares, (ensure you have turned off all the radiators at both ends and obviously the feed) and take out the valve bit completely, with a wet and dry vacuum cleaner running and an able helper.

Dig out the old washer.

Obviously, there will be increasing amounts of water emerging, so the machine may have to be emptied 2 or 3 times. You should be able to hold back the low pressure water with a finger and thumb over the outlets whilst helper empties the machine.

Or you could empty the system in the same way by loosening a connection with the vacuum cleaner underneath.

With the old rubber washer, out select a washer that seems to be the best match for the mechanicals, possibly about 8 mm diameter with a central hole, and refit with this.

Maybe fit a complete new drain valve ? - easy if compression !

Hope this helps.

Nick

[John Rumm]

Yes, you seem to get two different qualites of valves like these - the expensive ones which are at best adequate but a PITA, and the cheap ones which are a whole lot worse!

I did a hard piped drain on my system to avoid needing to use these things - I teed into an existing pipe at a low point, and took another pipe through wall to an adjacent gully. A decent quality (screwdriver operated) service valve takes care of the draining. So much easier than having to tit about with bits of hosepipe.

[chris French]

I almost did that. But never got around to it. But I did put a tee in at a low point under the hallway, and then put in an old rad valve to act as drain valve which was much better.

[Jan Larsen]

John Rumm wrote: > I did a hard piped drain on my system to avoid needing to use these

Yeah thats the kind of thing that was on the system in my old house in Dennmark, two ballofix valves undeneath the boiler marked "dump" and "fill", the fill one had a an extra ballofix sticking out on a tee to squeeze in chemicals like inhibitors and such, the rads had auto vents. when I swap my boiler that is what I want to have made.

//J