Bleeding air from radiators.

I have been getting some noise apparently from my central heating system and tried to bleed air, if any, from the radiators. These are probably quite old but have not been a cause for concern during the three years I have been in my flat. The problem I have encountered is that, while I am able to slacken off the screw on some of the radiators using a key intended for this, there are others where the key does not get a proper grip on the nut. I have tried, without success, using tweezer like pliers but there is limited space in which to work. Can anyone please suggest how best to deal with a problem of this nature. The last thing I want to do is to have to replace any of the affected radiators.

Alaric

Reply to
Alaric
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You will probably find the other end of the radiator has a blanking plug fitted instead of a bleeding plug.

The blanking plug can probably be removed and replaced with a bleeding plug.

Owain

Reply to
Owain

First thing to try is get a small metal drift and give the heads of the screws a tap with a hammer to shock the threads loose. Most of the time this will free them up. Try a new key. Your old one might be worn. Failing everything you can replace the whole bleed valve units for a couple of quid each. They just unscrew from the rad. Use a few turns of plumbers ptfe tape on the threads when you fit the new ones.

Reply to
Dave Baker

Some bleed valves will also have a slot in the end and can be turned with a screwdriver.

However failing that, if the edges have been rounded off so much you can't turn them with the normal key, I would suggest replacing the whole valve:

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(the whole valve unscrews - if you turn off both taps to the rad, you should be able to replace one without draining down and without spilling much)

Reply to
John Rumm

If that's the problem here (and it does sound like it to me) there's another solution I was shown by the plumber who changed my boiler recently, when he needed to bleed one of my radiators which was this affected.

Ordinary bleed keys (like

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a 'dished' end, which reduces the length of contact between the key and the valve head... you grind the end of the key so it's completely flat, and hey presto, the key will hopefully now work!

Obviously ideally best to change the valve though.

Reply to
Lobster

What sort of noise?

Radiators that need bleeding are cold/only warm, not hot, at the top.

Reply to
Dave Liquorice

Use a radiator key with a larger holding area. Many types on Ebay for very little money.

Use the pliers to hold the key to give you greater leverage.

Reply to
alan

+1. Avoid like the plague the keys that have a round brass barrel. They're stupidly machined to give very little grip on the bleed screw and to hurt your fingers.

Tim

Reply to
Tim+

Tim+ wrote in news:1313654016380662658.698887timdownie2003- nospampleaseyahoo.co.uk@read er80.eternal-september.org:

Note for future - avoid getting paint neat the valve. Exercise them occasionally (not just when you notice a problem).Ensure you have a good key.

Reply to
DerbyBorn

Do you mean the ones with the little brass T levers like these?

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are the only ones I use or give out as the reduced leverage limits the risk of overtightening and damage.

If pliers are needed then they've generally been overtightened.

Reply to
fred

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>> (the whole valve unscrews - if you turn off both taps to the rad, you

Depends on the radiator! Some of my radiators have slim rolled tops like this:

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- with the thread for the bleed screw cut directly into the body of the rad, with no intermediate plug.

Reply to
Roger Mills

In my experience with these is that they have insufficient area to grip and the minute tommy bar is often too small for the job.

or that someone hasn't got a lot of strength in their hands. or that they have been painted. or that there is some corrosion or scaling.

It may be true that the bleed screws on the OPs radiators have been over tightened and using pliers with the key to undo them may just give that additional leverage to undo them. I'm not suggesting the use of key and pliers to do them up again.

Reply to
alan

That's them. Deliberated machined to make them "cam out" at ridiculously low torque (and a pain in the fingers). Hateful things.

Tim

Reply to
Tim+

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>>>>>>> (the whole valve unscrews - if you turn off both taps to the rad, you

Yup that would make it harder. You may find in those circumstances that you can use the screw out of a new conventional radiator bleeding plug to replace the worn one in the rad. That assumes you can get the old one out in the first place though.

Reply to
John Rumm

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>>>>>

Heh. I had to throw out a radiator a few months ago during a refurb, and as I knew I had one radiator elsewhere in the house with a dodgy rounded-off bleed valve, I cleverly (I thought) saved the bleed screw from the old radiator to use as a replacement for the dodgy one, when I came to draining down and refilling my CH system a few weeks later.

Then come one Sunday evening, when I was actually ready to refill the system...now, where did I put that bloody screw? No idea. The only consolation I suppose is that I *didn't* subsequently find it 10 minutes after refilling... several months later I still haven't done so, actually!

Reply to
Lobster

I have been getting some noise apparently from my central heating system and tried to bleed air, if any, from the radiators. These are probably quite old but have not been a cause for concern during the three years I have been in my flat. The problem I have encountered is that, while I am able to slacken off the screw on some of the radiators using a key intended for this, there are others where the key does not get a proper grip on the nut. I have tried, without success, using tweezer like pliers but there is limited space in which to work. Can anyone please suggest how best to deal with a problem of this nature. The last thing I want to do is to have to replace any of the affected radiators.

Alaric

My thanks to all who responded to my query.

There are no blanking plugs on any of the radiators which, as I have now ascertained from the previous owner of my flat who I met by chance a few days ago, are probably more than twenty years old. That said, the radiators all give warmth over their entire surface area when the system is up and running. So, bleeding is probably not the solution. The noise would seem to be in the pipework and is intermittent which does not make tracing the source any easier.

One of these days I shall be having the plumber come to service the combi boiler and I shall see what he has to say.

Again, many thanks to those of you who gave of your time.

Alaric.

Reply to
Alaric

After a workshop-tidy-up session this afternoon guess what I finally found?

Reply to
Lobster

brass monkey :

My usual scenario is I buy a multipack, carefully consider where to store the half-empty pack, and find one already there.

Reply to
Mike Barnes

In message , Mike Barnes writes

The new workshop was meant to save time by combining several activities to one spot.

In the event, I still have to walk to the abandoned ones looking for the bits/tools I *know* exist.

After 12 months I am just about able to go directly to where I put the thingummyjig but only if I have actually used it recently:-(

>
Reply to
Tim Lamb

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