Possible to replace a bleed screw?

[rhysjc]

Evening all,

I got a bit excited after bleeding this rad the other week and snapped the head off the bleed screw when tightening with the key. Is it possible/relatively simple to just replace the screw? If not, can the whole valve be replaced with the more “modern” kind that you bleed with a flat head? Looks like possibly you could get it out with an Allen key and then screw the new one in?

 

[gas112]

.

Air Vent

Brass.

www.toolstation.com

you need big allen key to take existing plug out which will be pretty tight after all these years

 

[rhysjc]

@gas112 thank you for that! I’ve been searching all combinations of bleed, screw and valve. Didn’t know it was called an air vent! Do I have to use that, or can I replace with a modern valve? Not particularly bothered as replacing the rad in a few weeks anyway, but just curious

 

[gas112]

@gas112 thank you for that! I’ve been searching all combinations of bleed, screw and valve. Didn’t know it was called an air vent! Do I have to use that, or can I replace with a modern valve? Not particularly bothered as replacing the rad in a few weeks anyway, but just curious

best to use one of same on an old rad like that

 

[rhysjc]

Makes total sense. Best way to not get soaked? Assume if I just take the old one out I’ll need a bucket handy!

 

[terryplumb]

Just change the radiator, sooner than planned maybe. Not worth wasting time on that rad.

 

[rhysjc]

@terryplumb we’ve got a plasterer in that room soon, would rather not put the new one in till he’s done

 

[terryplumb]

Is he plastering the wall that the rad sits on ?
As you bled air from that rad ,Isn't it heating anyway ?

 

[rhysjc]

Yep he’ll be plastering behind it. It is heating, that’s no issue. But I need it off for the plasterer and thought I needed to bleed it prior to taking off, otherwise I’ll have a vacuum at the top?

 

[ChrisJP]

Yep he’ll be plastering behind it. It is heating, that’s no issue. But I need it off for the plasterer and thought I needed to bleed it prior to taking off, otherwise I’ll have a vacuum at the top?

Before you take the rad off the wall it'll need draining by loosening one of the pipe connections to it at the bottom. Once you've done that the flow will quickly stop until you let air into the top of the radiator. So in the absence of a working bleed screw you'll need to take out one of the plugs in the top connections - either the one with your broken bleed screw in it, or the one at the other end which won't have a bleed screw. They'll be very tight in an old radiator so you may have quite a fight to get one out. An alternative, since you're throwing the radiator away, is just to drill a hole in the top if the radiator.
Be prepared for quite a bit of water to drain out - could by anywhere from 5 to 10 litres.

 

[ChrisJP]

Oh and the water will be black and sludgy and will stain anything it comes into contact with!

 

[terryplumb]

If you close both radiator valves ,then loosen the joint ( rad valve to rad tail) on one side of the rad.some water will drain out. If it stops because of a vacuum fit a cap on the tail. Then do the same on the other sides valve.
Carry the rad outside still full of water. You can drain it outside then trash it !!

 

[rhysjc]

Thanks everyone for your input. I've acquired a radiator spanner, plumb tub and a stop cap for the valve once I've got the rad off. However, I'm not sure I have total faith in the TRV that's currently fitted even for the short time before I get the stop cap on. I've checked the pin and there is a bit of movement in it, may 5mm tops. However the TRV collar seems to just spin once I hit either 5 or 0, I'm expecting there to be no movement at all beyond those points?

 

[pcaouolte]

It is safest to remove the TRV head and fit a decorators cap to hold the pin down and keep the valve closed.
https://www.screwfix.com/p/drayton-35mm-white-radiator-valve-cap-5-pack/5649r

 

[rhysjc]

@pcaouolte I was hoping to be able to get away with putting turning it down to 0 then capping the the radiator side of the valve. I’ll see if it eventually cools down otherwise decorators cap it is.