Clamp on drain cocks?

[MissG]

Recently I bled my radiators and after all the air had gone no water came out and the system has all gone pretty cold. Someone suggested manually filling my tank up to increase pressure but it's not accessible. The next suggestion was to use the drain cock on the front of the boiler to pump water in through a hose but as it's so old it won't unscrew.

Apparently you can buy drain cocks that you clamp to a radiator pipe and as you screw it on it bores a hole and you can then feed water in that way. Has anyone heard of one of these or used one before and will it work?

Useless young female here so please don't be too technical in your reply. Thanks

 

[Softus]

Recently I bled my radiators and after all the air had gone no water came out and the system has all gone pretty cold.

You might have made the mistake of venting while the pump was running, and actually pulled air in.

Someone suggested manually filling my tank up to increase pressure but it's not accessible. The next suggestion was to use the drain cock on the front of the boiler to pump water in through a hose but as it's so old it won't unscrew.

What was the symptom of the original problem that you were trying to solve? Why did you think it was necessary to vent the rads?

Apparently you can buy drain cocks that you clamp to a radiator pipe and as you screw it on it bores a hole and you can then feed water in that way. Has anyone heard of one of these or used one before and will it work?

The downside of these is the risk of a leak - you wouldn't be able to seal it if that happened. It probably wouldn't leak if the pipe was in perfect condition, but you don't know how old or worn the pipe is, and how thin the pipe walls are - they might distort, fold or collapse or when the cutter is forced in.

In short, the only time I'd ever a clamp-on connection is on a cold supply, and only then if the pipe could be quickly isolated, and only then if someone was holding a gun to my crotch...

 

[sm1thson]

Someone suggested manually filling my tank up to increase pressure but it's not accessible

are you sure your system has a tank? -if it does you really need to find a way of accessing it.

 

[MissG]

Thanks for your reply. I originally bled them because the tops were cold whilst the bottoms were hot and one in particular made constant clicking sounds. I certainly didn't check whether the pump was running before I did that so I may well have pulled air in as you suggested.

A friend of a friend (not sure if he's a trained plumber) looked and suggested putting the clamp thing on the towel rail pipe because it's new, the pipe looks in pretty good condition from the outside and the bathroom has a wet-room floor so if any water leaked out whilst he was fixing it it wouldn't be a massive problem.

Your reply makes me a bit concerned in case this isn't the best way to go about it but as we can't really access the top of the tank and there are no other drain cocks to use I'm not sure if there are any other options?

 

[JohnD]

Tell us more about where this tank is, why you can't access it, and if it is full of water or not.

 

[MissG]

The boiler is in the utility on the ground. Just above it to the left is a big tank wrapped in red stuff which appears to have a top section and a bottom section. The guy who looked at it said the bottom part of the tank fed the taps and stuff and that was OK. The upper tank is apparently what feeds the CH and the part of it is visible from the utility but you can't see the top of it - there is a small hatch in the ceiling but when you look up there all you can see is boarding around it and pipes which look like they're from the upstairs bathroom.

I guess there might be access from the flat above but no-one's living there at the moment so we can't get to it. I really have no idea how people have accessed it in the past - I've just moved into this flat.

 

[JohnD]

the tank you describe is probably not the CH Feed & Expansion.

Can you post some photos?

 

[nickso]

sounds like a combination cylinder which doesnt feed your central heating.

are you sure your central heating isnt a sealed system?

if its not there could be another tank somewhere else

edit:- unless its an elson tank with some aftermarket insulation added