Radiator Bleed Valve

RHemmings

I may have led a sheltered life, but I have never seen a radiator bleed valve like this. I photographed it with a millimetre measure for scale. What tool do I need to bleed this radiator, please? 

ThisIsWeird

Could we see it straight on, please?
You are familiar with normal rad bleeders? 

RHemmings

ThisIsWeird said:

Could we see it straight on, please?
You are familiar with normal rad bleeders? 

Thank you for your reply. 

I've never had a problem bleeding a radiator before with what I thought was the standard tool, and a bleed valve on the end of the radiator. The valves on these elderly looking radiators are on the back, at the left (looking from front) top. 

They are facing the wall and I can't get my phone camera far enough away so that it will focus. So, all I get are the following blurry images. 





The bleed valves on all the radiators are the same. On the heated towel rail in the bathroom (which looks much newer) I have this:



As I read online while trying to work out what to do, the towel rail bleed value can be loosened with a flat-head screwdriver. but, unless they are hidden by paint, I can't see any slot in the bleed valves for the other radiators. 

Since the first time I actually bled a radiator, I've been in places where the bleed valves look like the following, and the key/tool I have fits. Which it doesn't now as it's way too big. I haven't ever looked into bleeding radiators over and above reading a sequence of steps, following them with the first tool I bought, and it just worked. So I never felt the need to research further. 

Bookworm105

it is a bleed value, male rather than female
insert square hole key and turn.
Have towel at hand to soak up the predictable squirting water.

RHemmings

Bookworm105 said:

it is a bleed value, male rather than female
insert square hole key and turn.
Have towel at hand to soak up the predictable squirting water.

Thank you. Sorry if I'm being ignorant, but I'm not sure which tool to use. My current tool has a square hole, but it's much too large for the bleed valves I have. Would it be possible to ask if you can link to the appropriate tool? Or post a photo? 

teaselMay

It looks as though a standard radiator 'key' with a square hole is what you need. Towel or rag against it as you turn to catch the water - watch not to scald your fingers 

RHemmings

teaselMay said:

It looks as though a standard radiator 'key' with a square hole is what you need. Towel or rag against it as you turn to catch the water - watch not to scald your fingers 

The radiator key with a square hole that I have is far too large. Hence I'm confused. 

ThisIsWeird

RHemmings said:

ThisIsWeird said:

Could we see it straight on, please?
You are familiar with normal rad bleeders? 

Thank you for your reply. 

I've never had a problem bleeding a radiator before with what I thought was the standard tool, and a bleed valve on the end of the radiator. The valves on these elderly looking radiators are on the back, at the left (looking from front) top. 

They are facing the wall and I can't get my phone camera far enough away so that it will focus. So, all I get are the following blurry images. 





The bleed valves on all the radiators are the same. On the heated towel rail in the bathroom (which looks much newer) I have this:



As I read online while trying to work out what to do, the towel rail bleed value can be loosened with a flat-head screwdriver. but, unless they are hidden by paint, I can't see any slot in the bleed valves for the other radiators. 

Since the first time I actually bled a radiator, I've been in places where the bleed valves look like the following, and the key/tool I have fits. Which it doesn't now as it's way too big. I haven't ever looked into bleeding radiators over and above reading a sequence of steps, following them with the first tool I bought, and it just worked. So I never felt the need to research further. 

Ok, you know what a standard bleed valve looks like - it's that side-on screw in the bottom pic. And, when in position, it looks like the top-right pic adjacent to it, yes? And you do have the key for this, but you are saying that the weird rad's screw is much smaller, so the key doesn't grip? Is that the issue?
Any chance it's because the head's been rounded?
Ok, the weird screw sticks out, yes? So, you should be able to grab it with pliers, or a mole-wrench to undo it? If so, then if you remove it completely, you should be able to take a photo and some measurements, and see if new screws - like in that example - will fit.
To do this, you'd need to fully close both rad valves so no water comes out after the rad has depressurised. The lockshield valve's current position should be counted so it can be returned to the same position - note how many full and part turns does it take to fully close.

Micron

Try using a 5 mm A/F spanner if you have one, if not a small adjustable spanner should suffice, but be very gentle.

Unless you really need to bleed the radiator I would leave well alone, if you are very unlucky and the bleed screw breaks there may be no alternative other than taking the radiator off the wall to fit a new one.  Good Luck

 

RHemmings

Thanks all. I'm on a 6am train to Manchester tomorrow morning (moneysaving compared to later trains and longer in Manchester). So, it'll probably be tomorrow evening before I can reply again. And more likely Sunday. 

Just some points: When I've bled radiators before, I've always used thick towels and let the water spurt out before I closed the valve again. I note that general advice is to wait until the sound is indicating spurting then close before it does, but I like to see the water. Yes, with the radiators cold. 

I did try to use a small adjustable spanner on the valves, but it wouldn't grip. It could be that I didn't have the spanner positioned properly or the head of the valve is already rounded. If I was going to use pliers, then I think I'd want to be removing the valve and then replacing with a new one. Otherwise I think I might be storing up problems for later. 

I'm not sure if I need to bleed the radiators. But, they do heat up quite slowly. If it was a doddle to bleed the radiators, then I would do it as a precautionary measure. 

ThisIsWeird

Micron's caution above is very valid, so when you do try the first rad - ideally one you can manage without in the worst case scenario - then make sure both rad valves are fully off. That way, only a limited amount of water should come out before it stops.
Mind you, the worst case scenario is probably that the screw just snaps, so you'll be no worse off than you currently are!
As to how to bleed, there is no precision required, but there is no reason to let it squirt either 'cos you could make a mess. Just open it slightly until you either see water dripping out or you hear a hiss or gurgle. Hold cloth to catch any water. Then just let it dribble until there's zero hiss or gurgle. That's it.
(Rad valves open as normal during this process, and CH off.)
I think it's worth trying a clamping wrench - mole type - on one. It'll either work, or it'll snap, but you'd be extremely unlucky to end up with a leak. And you'll have fully closed off each rad valve beforehand - opening one again to allow successful bleeding. 
NB: make 100% certain you are trying to turn the screw the correct way!
The main symptom of air in a rad is usually distinctive cold tops in the first instance - are yours? When you successfully bled your other rads - ones with ok screws - did they have any air in them?
Lots of air could, I guess, slow down a heating speed, but there are many other causes for this too which we can explore.
You haven't told us what type of system you have; make and model of boiler, combi or 'heat', pressurised or wee F&E tank, etc?