Thanks for uploading. This is a great instructional video, with clear and easy to follow guidance. Much appreciated.

Cheers, what I found was for the key is to zip-tie to the pipe at the first radiator!

Super useful. We are useless at diy, and my husband was most grateful I found you. Very well explained. 😅

I love this channel. All the things my dad did, but never had time to teach me. 💗

As someone who already knows how to do this, I can wholeheartedly say this is the perfect video for someone who has never done it before. Short, simple, yet detailed enough to get the points across I salute you sir!!

I knew how to bleed a radiator but not how adjust the pressure but now I do. Thanks for showing me Stuart with a clear, straightforward video. Brilliant!

ONE OF THE BEST DIY VIDEOS IVE EVER WATCHED.

For those without the modern fancy bleed valves I would suggest placing an absorbent cloth between the top of the rad and the wall as when the valve is loosened the water does not always dripped conveniently down. I have an older installation as many do, which is not pressurised so no need to look for that top up loop. Finally the “air” is more often actually the product of electrolysis between copper pipes and steel rads. Smell it!

It now makes sense why I couldn’t get water out the radiator when trying to bleed it. I’ve now found what my issue is. Still need a plumber, but this will save me a few quid as I know exactly what needs doing, found a leak so know why I’m losing pressure, BIG THANKS!!!!

Best how to bleed radiator video I’ve watched. Clear, concise and also including relevant further/important information. Not many folks include info about the possible pressure drop after doing this, and how to fix it. Many thanks.

This video is great for people with normal radiators. I'd like to add something for people like me who bought fancy pants vertical radiators before knowing anything about bleeding the system. Sometimes the bleed valve is hidden on the back at the top and incredibly awkward to reach...AND a regular radiator key will not fit between the wall and the valve!! Finding a key that does fit is tricky but I ordered an ok one online. You have to bleed it blind, back to front and water spills down the wall no matter what! I would say don't bother but they do look nice!

Very useful - Thanks! All our radiators are now heating up properly. 😀

The filling loop needs to be disconnected after use. After you removed the filling loop attach the caps on either end of the valves. This is so if the valves was to pass then your system will not get over filled and endup blowing off the Pressure relief valve on the boiler. Always get your boiler serviced yearly. Great videos. These help my customers from time to time

I’m a keen fan of your videos Stuart, but as a heating engineer of many years’ experience, I’ve got to pull you up on a few points on this one: You’re assuming everyone has a sealed (pressurised) system like yours. That’s not the case, there’s no such thing as a standard system in the UK. The first step is to understand what type of system you have. If you have a combi, or any system with a filling loop, or filling valves, then your advice is generally correct. But if you have a small tank in the loft, or at the high point in the system, then you have a vented system which is not pressurised and has no filling loop/point. There’s a lot of niche system designs about too, which are either pressurised, or unpressurised, but not so easy to identify. When you do bleed the air out, make sure the system is off and cooled down to avoid scalding. Hot water at 1 bar pressure is no fun when it hits you! Also, your comment that ‘air’ is what is causing the cold spot at the top of a radiator isn’t always true. Internal system corrosion causes gases which can give the same symptoms. These gases can be flammable too, so some caution is advised. Unpressurised, vented systems can suffer from “overpumping”, where air is sucked into the system and collects at the top of radiators. My advice would be that if you’re regularly having to bleed radiators, then it requires investigation by an expert. Lastly, if you have a removable filling loop hose, it shouldn’t be left connected. When you’ve repressurised the system, the valves should be switched off and the hose disconnected and stored where you can find it for next time you need it. I think leaving the hose connected contravenes water bylaws in some areas.

Hi Gary from the UK here I just watched your video about the first quarter of it and know that you know what you're talking about, as I'm an old heating engineer DON'T forget to tell people to get the aluminium vent key and NOT the brass key as the brass key could damage your air vent on your radiator, and all I can say is well done Keep up the good work with the videos

Looks good. I was told by a gas safe engineer that the filling loop flexi cable should always be disconnected unless you are filling it up. I’ve never bothered disconnecting though.

Worth saying that radiator keys are available at DIY outlets and your favourite online retailer. Can never have enough.

7:04 Oi, no need for cussing, Stuart! 😂 Love these Basics videos, although some of your info doesn't apply to my house in The Netherlands (like different electrical stuff, and the heating in our house is 'distrct heating' - the heat comes from a nearby powerplant). But nevertheless useful and entertaining stuff!

What brilliant timing. Have air in one of my radiators not done this job before. Thank you for making this video will help me to do the job. When I've asked about should I do it with heating on or off got a yes to both😳 very confusing but now I know plus adjusting the pressure a bonus. Probably looks an easy job if your in the know. Thanks

Thank you so much for doing this video this is definitely the best tutorial on how to do do this I have a radiator that's cold at the top and one that's cold at the bottom I never knew that you had to reppressure the system brilliant video thanks Stuart 😊

Perfect instructional video. Thank you for clear concise instructions!

I’d add water from the mains first and all the way to the upoer limit of the pressure interval - in this case 1,5 bar. Since the mains is at a higher pressure it will release a tiny amount of air when let down to 1,5 bar. Then wait a couple of days before bleeding the radiators so you won’t have to do it twice.

Very timely reminder of something I had completely forgotten to do for way too long! I think we were running more on air than water!!

Thanks for this. I have never done this before, but it wad easy.

Nice one mate useful for new homeowners 👍🏻 hope your keeping well

Good video for the novice & something we should all do from time to time to keep the heating system at peak efficiency. I have been doing exactly this on my gravity fed system this week after I drained it down to have a new stainless steel HW cylinder fitted & new Tado smart valves on nearly all the radiators. I really struggled for a day or so to get all the air out of the system which somehow "air locked" itself which prevented the boiler from firing - no flow. Managed to clear the air lock by backfilling water into the downstairs rads & then bleeding everything again & again & again until the boiler would fire & stay running. I added inhibitor & three days later I can still hear the odd bit of air gurgling in some rads. I'll leave it week are so & bleed the rads again.

I wish this video existed when we moved into our house! Would have saved me a lot of worries! A little tip Stuart, I hang my key underneath the boiler on a bit of elastic, never loose it! (and got spares but don't really know where they are atm ;) ) very clear and complete explanation! Can't wait for the next vid!

Many thanks!

Thanks Very good way of explanation.

What a great informative video. Just what I needed ❤

Very useful and clearly demonstrated information, much appreciated Thankyou🙂

Thank you sir for your clear and concise video

Oppps 02:21, I think you meant to say "I don't think there is a lot of air in here" 🤭

thank you for your demonstration, it's very helpful for me ！

Very well explained. Thanks a lot!

Thanks a lot. Brilliant content.

Thank you! That was clearly explained.. I was going to drain mine when it was on and hot.🤔

Thank you so much for sharing this video ❤❤

Radiator key 1: magnet to the side of the boiler 2: hang on the key rack

Thank you. Did for the first time.

Thank you so much. I found your video really helped me.

Always very handy

Thank you for your nice teaching 😅🥰🙏😊

Some boilers don't have an easily readable guage like the one shown in the video. Mine has a digital display for which I have to press a combination of buttons to see the current pressure reading. I only found this out by downloading my boiler's instruction manual from the interweb. So it's still possible to do the re-pressurisation but with an extra step.

Fantastic video

Great video thank you 👍

Very helpful indeed

Great video !! thank you

On your earlier energy tips video you didn't mention refilling and I thought given it was aimed more at beginners that was a pretty important thing to miss - if you don't know that you should bleed them and you can't figure out how to do it you're almost certainly not going to know about how to refill the loop or probably even that you need to until your boiler isn't working and you have to call a plumber who will immediately be able to spot the problem then bill you a call-out fee. Therefore this is a nice erata to that :)

Thank you very helpful

A very good vid, thank you.

Very helpful 👌

Can someone define what "heating system turned off" means? Like I have a valve that stops the water I think from entering the radiator. But the main boiler I dont control in my apartment complex. Does the boiler need to be off, or can you use the valve to switch it off instead?

Very useful 👌

Thanks very much .

Thank you.

Air travels upwards in water so the highest radiator on the loop will catch all the air. Theoretically this is the only rad that needs venting, always worth checking the others though.

good video !

The best place to keep the rad. key is on top of the boiler, or if this is too high up on the wall, bend a piece of wire into an S hook and hang it on a pipe under the boiler. Good advert for B&Q jugs!!!

Really enjoying your channel. What about balancing radiators ?

Another top tip is you can hear it too … like a clock ticking also flat head screw driver … and I towel to protect wall ect

What a coincidence. Just about to drain and refill my system, and this shows up in my feed 🤣

Thanks appreciate.

You’ve reminded me to do mine 😂

nice video

Finding the key is the key problem... It is used once a year for max 30min. A good practice is to put it on a small string and hang it on the drain valve of central heating unit/pump, this way it is always there when you need it.

I noticed how clean the water was coming out of your radiator. In my (30 years) experience this is rare - I would just say to people not to worry if their water comes out very dark. I describe that as "dead water" i.e. it has done all its "reacting" and should no longer cause rust inside your radiators. The worst thing to do is keep draining the system and refilling with just fresh water, as this will then start to further rust your radiators. If you use a rust inhibitor then this should also prevent rust, but again it does NOT need doing regularly!

Dont forget to start on the ground floor with the radiator furthest away from the boiler

A modern boiler might not have an external filling loop! Some have an cold feed and a tap arrangement integral with the boiler. I used to loose my rad keys too ..... until I got wise and tied a string loop to it and hang it from the boiler ;o)

My boiler is in the loft with some pipe work in the cupboard in the bedroom. Interesting watch.

It helps to have the bleed valve at the end of the radiator that is highest! Radiators should not be perfectly level. When you have finished bleeding, leave the radiator key on a piece of wire, string off one of the boiler pipes, so you can find it next time!

Any particular reason you say make sure the system is off? I have always done with it on and not had any problems. Also, our Worcester Bosch boiler has on the underside a brass fittting with a blue plastic lever through the middle. All you need to do to add pressure is pull the lever down slightly and let go when up to pressure. One time it hadn't been done for a while and was very tight, I was afraid the plastic was going to snap, but it released with some persuasion, so I would recommend pulling this lever down just for a second maybe every 6 months just to make sure it doesn't seize up.

Did you ever manage to board your loft? Would be good to see a video on how to do it...

I don't want to add to the pressure Stuart, but how do you follow that, it was a bleedin' good video ! 😜

Is there any particular cost or benefit to pressurising the central heating closer to 1 bar or 1.5 bar, or is it just all uniformly good in that region?

In my My new build property (2019) my radiator in hall upstairs I can hear water going through it all the time. The radiator all works fine and central heating is all working,I’ve not tried to bleed the rad just in case it all stop working knowing my luck, Any thoughts what it might be. Another great and very informative vid mate.

That boiler is very old, like mine 20 years ago. My previous one had 2 keys under the actual boiler to turn, and my new one is just one lever.

You have to check that your vessel inside the boiler is charged properly as this can affect the system pressure

Thank god i found this video. The air has come out but no water, is this normal? 😢

Can you give me some advice e please, my living room radiator isn't heating up as well as all the rest, we flushed out the system, took the radiator off and run a hose through it, bled the radiators and it's still the same. If we switch off all the other radiators it gets hot and works. I've tried to balance the radiators and it made it worse. I'm not 100% sure if I got the right sequence. Our condenser boiler is down stairs in the kitchen and the pump and cylinder tank is in the upstairs bathroom. All advice will be greatly appreciated. Tia

Awesome new friend here 🤗👍

Hi my problem is that the en-suite radiator is not heating up after a new radiator was installed in the hall . There’s water in the en-suite one but it stays cold. Any advice would be greatly appreciated

I have hot and cold but you need to turn it on & off with screw driewer so can you tell me should turn on cold then hot? because your has black valve

I have a new radiator and combi boiler with radiator cooler at the bottom, any ideas please

I know I have one radiator that if I try to bleed, water comes out around the valve and feels like it will pop out rather than turn to bleed. Anything I can do about it?

If you have open fire back boiler and oil central heating system. I assume you dont need to pressurize the cylinder tank / boiler after bleeding? I came here to find valve for those bloody towel racks lol

Where did you find your radiator key? Wonder if mine's there too. OK I'll get one of Amazon.

Nooice!

Why do it with the heating off and do you have to start at any particular point. Ie bleeding car brakes you start fron the furthest away corner?

Where can I buy the white plastic covers with the small drain hole ?

Can someone help with advice I got an boiler when the boiler is not heating anything the pressure is 0 when the boiler turn on and start to heat the pressure is going up to 3 bars ... also its not heating when you just want to warm up the watter you have to have heating on to warm up the watter any advice ? Thank you

Great stuff.... Again. Does the pressure rise as the water heats!? My boiler is off as I type and below 1 bar. When the heating is on it goes up to nearly 2bar. Therfore I assume I need to increase pressure? As you have demonstrated

How do you "bleed" a boiler, if you swap the heating element, you fill it with water and that air needs to go somewhere Or do you do it via the water valve in the boiler when you want to remove water?

Put the radiator key on a hook next to the boiler. It's where you should end the procedure anyway, when adjusting the pressure. That way, you don't forget to check the pressure after letting the air out the radiators. Then put stickers in EVERY key bowl and drawer to remind you that you had that great idea, when you search for the key AGAIN in one year...

Hi guys, I have an issue with only one rad in my system. When the CH is on this rad wants to remain cold, however I can feel that the lockshield side gets hot aswell as the pipe, but the TRV side remains cold and will only ever get lukeworm. When I remove the TRV from the rad and open the TRV, there is water gushing out. Does anyone have an idea of what may be going on?

nice one but not everyone has a combi - how to do this on a boiler that is service only would be helpful as ours has no pressure gauge. Or is it likely to pressurise itself in that case?

what does it mean if the bottom of the radiator is cold & the top is hot instead of the other ways around?

Hi buddy. My room radiator doesn't work on low numbers (between 1-4). But when I set it on 4 or above, it starts working but it over heats the room. What could be the issue and how can it be solved ?

What if you don't have a pressure gauge?

I don't have the radiators that have the bleed nipple on the end. Mine is at the back under the lip of the window sill and is very hard to open. I do have air in the radiators but as I don't know which way to open it, I am a but hesitant to do it. I keep forgetting to tell the landlord when the yearly boiler inspection is due.