How to Change a Thermostatic Radiator Valve Without Draining The System

so you want to know how to change one of these thermostatic radiator valves for a new one and that's probably because you can no longer increase or decrease the temperature of your radiator or maybe you just want to change a lock shield valve for one of these trvs and i'm going to show you the diy how you can do this job without draining the heating system this applies to a gravity fed system but also a pressurized system and doing this without draining the system means that we can not only do this a lot quicker but we can do it without having to replace any of the inhibitor that's in the system like you would if you had to refill the whole system and i'm going to show you exactly how to do this job step-by-step hair on the diy guy [Music] [Music] so i'll run through the tools that you're going to need first and then we'll crack on with the job but before we do that if this video helps you out hit the like button for me because that really helps this video to reach and help more people just like you on youtube and if you like all kinds of diy content plumbing electrics construction tool reviews then hit the subscribe button down below because i've got loads of stuff on the channel and plenty to come in 2022 so let me run through some of the tools that you might need for this job first things first make sure you've got plenty of towels and things like that because unfortunately this job is not completely water free you will always get a little bit of water so make sure you protect any carpets and have something ready to catch a little bit of water you're also going to need an adjustable spanner a screwdriver or radiator key whichever you have at hand i can't find my radiator key so we're using a screwdriver i've got some ptfe tape in there um maybe not necessary but always good to have some nearby in case you can't get the olive to reseal and these are tank buns or rad valve change kit whatever you want to call them let me explain a little bit more about what these are plumbers will have these in their bag already but for you diys that have a gravity fed system which means you'll have a tank in your loft if you're not sure go and have a look but for you guys that are doing this on a gravity fed system you're going to need a couple of these so that we can pull a vacuum and that we don't get wet in the process of changing the trv i'll stick a link to these buns in the description so that you can go and grab yourself some they're inexpensive and they make this job really easy now you won't need those buns if you're doing this on a pressurized system but we'll go through more of that in a second as we make a start now the last thing you're going to need of course is a trv this is a 15 mil thermostatic radiator valve made by drayton they're the ones i usually use because they're really simple and really reliable and actually pretty inexpensive as well and i'm not paid to say that they're just the ones i like so inside here you get the 15 mil angle itself which has a decorator's cap on they all come with a decorator's cap on that just closes off the valve and you have the thermostatic head in the box as well you also have a tail for the radiator now we're not going to use that today because this is a simple trv swap but if we were installing this on a new radiator we would need that tail but you can chuck that bit back in the box for this job because we're not going to need it now i'll stick a link to this trv in the description so you can go and grab yourself one let's make a start should be a simple easy little job one that people find scary but let's get it done so the first thing you need to do is turn off the power to your boiler you don't want your heating system calling for heat whilst we're doing this job so find the switch for your boiler and turn it off so if you're doing this job with a combi boiler the next step for you will be to release the pressure on the system with a radiator key or you can use a screwdriver now all you'll need to do for that is undo this bleed screw you can see you've got a little trickle of water there basically all you need to do is drain that off until you have hardly any water or a very very light stream of water coming out of your radiator but i'm going to stop that there because this is a gravity fed system with tanks in the loft and i don't need to do that step at the moment so now i'll show you where these tang bungs come in handy on a gravity fed system this is your central heating tank chuck all the crap by the way so take the lid off of it so you can see what you're doing rusty inside so within your header tank there's two pipes that you need to bun the first one is the expansion vent pipe so grab hold of that pipe and make sure you twist that bung until it's firmly inside the pipe you want to make sure you get the perfect seal if you don't get the perfect seal on these you won't pull a vacuum and you're going to get wet so take your time making sure you get that bung in the pipe perfectly and the second pipe that we need to bun there's plenty of rusty water in here so it's not the easiest one to show you but there's a cold water feed at the bottom of the tank there so with our second bung we're going to go in to that cold water feed and again make a twist and motion whilst you push this in to get a nice firm bung so that's the bungs in let's wash all this maggie water off my hands and we'll move on to the next step so if you're following along with a gravity fed system now you have your boiler off and you have your buns in your header tank so we are pulling a vacuum now what you need to do is open up the trv so the one that you're working on make sure that valve is open for the other valve on the radiator in this case this lock shield valve should be turned off so we need to close that one and it'll close off by turning it in a clockwise direction there we go that's that valve closed next up protect the carpet because we're going to head over to the bleed valve and we're going to test to see whether we're pulling a vacuum so we're going to open this up and we should see a steady flow of water and it could take some time but we want to see that flow reduce and possibly even stop and then we'll know and that way we'll know that the vacuum's pulling down on them two bungs that we've put in the tank and that will be good to go ahead and replace the trv we have a definite reduction in pressure there so that means our tank bungs are working if they weren't that would still be a constant pressurized flow of water so we can now do the bleed valve back up so where are we at if you're on a gravity fed system you've got your boiler turned off you've got the bungs in the tank and you've tested the bleed valve to check that you have a good vacuum if you're on a pressurized or combi boiler system you've got the boiler turned off and you've released the pressure on the bleed screw at the top there now earlier we turned off the lock shield at the other end of this radiator now what you need to do is turn off that trv as well and before we go any further we'll prepare our new trv because there is going to be some water coming out here and if you're working on a gravity fed system you don't want this to be open for too long because if we lost the seal in the tank you're going to get wet so we need to be fairly swift so let's get the new valve made up and ready so take your nut and olives off because we already have them because we already have them on the pipe we're not going to be changing those they can be chucked out of the way for now when we fit this we can leave the decorator cap on because that keeps the valve shut now there's a reason we want to keep the valve shut let me explain why now the reason we want to keep the valve shut is because when we undo these nuts if we're in a model we can quickly put the valve on now if we didn't have the valve shut water would still come spewing out and we'd have to fit both of the nuts and the olives back onto the angled valve here whereas if we just have it shut we've only got to tighten one of them nuts up to stop water coming out of the system so i definitely recommend leaving the decorator cap fully on for now lay your valve somewhere close by so that you're ready to work and ready to get that valve back in place so the next step's the same whether you're on a pressurized system or a gravity fed system we're going to crack off the bottom nut not fully but just loosen it off very slightly and you'll see you're getting a slight drip on this so make sure you've got your towels and your buckets and things at the ready because you will get a little bit of water coming out of there next up we're going to support the valve so that we don't damage the pipe especially considering in this property we're on micro ball pipe so it's not very strong if we go cranking this top nut without supporting the valve we're likely to damage or misshape the pipe and that may make it harder to seal that back up worst case scenario we may end up having to replace a kinked pipe and we don't want that so we're going to support this valve and we'll do that with a pair of grips and we'll just crack off that top nut there you go that's gone wind that nut back with your fingers and you'll see at the moment we haven't got any rush of water coming out or anything like that but make sure you've got all your buckets nearby because once we move this valve away from the radiator we will get some water coming out this is a really good one not much water at all just a drip really now this is where you want to hurry up a little bit because if our vacuum was to break if you're on a gravity fed system we would then have a considerable amount more water coming out of this radiator so we need to hurry this up a little bit so all we need to do now and this can be a little bit tricky depending on the pipes this micro bore is not too tight so we can move the valve away it's even easier if it's on plastic pipe but sometimes if you've got copper bite if you've got a copper pipe tile coming out of the floor where it's been screeded over or something like that it can be harder to maneuver the pipes so be careful don't bend the pipes in the process crank off that bottom nut fully and then we can simply remove the valve hopefully with not much water coming out either just let the worst of that water come out and we can pull that valve out of the way catch some of this water grab your new valve and just put that new valve in place and you can see just laying that valve in place like that has stopped that flow of water and then we can start to do up our nuts can be a little bit tricky to get them all back in place might take a little bit of wiggling so because we've got this valve shut nothing can come out of here we're safe with that so we haven't got to worry about that one for now we just do this one up here and because they're on an olive you could use joint in compound but typically i don't they don't need to go in with ptfe tape or anything like that you can just do the nut up the olive will reseal 99.9 of the time and shouldn't leak so we don't need to worry about ptfe tape or anything like that just do this bottom nut back up for now again i like to use my grips just to hold the valve steady whilst i nip that nut up and that way i won't damage the pipe so our bottom nut is done up now what we need to do is just push the valve closer to the top nut and you can see we can just do that top nut up again support the valve like we did before so it doesn't twist and just nip up the top nut okay so that's the two nuts done up nice and tight and the angled valve is now installed next step grab your thermostatic head and we'll install that in place of the decorator cap so go ahead and remove the decorator cap which in turn opens up the valve keep these knocking around somewhere clues in the name when you might need them installing the thermostatic head is very very simple make sure that it's fully open because that makes it easier to install give it a gentle push and you'll actually feel that you're pushing that pin in and then just turn the collar and you just gotta do that up hand tight and that is our trv installed don't forget to open up the lock shield valve on the other end of your radiator make sure that for now you've still got this bleed nipple closed off all we now need to do is reinstate the heating system if you're on a pressurized system with a combi boiler open up all your radiators and replace that lost pressure from the boiler filling loop if you're doing this on a gravity fed system with the bungs in the tank what we'll now need to do is go up into the loft and remove those bungs now we can go ahead and remove the buns and you'll probably hear and see a little bit of gurgling but don't panic that's normal put the lid back on the tank and any insulation turn the boiler back on and now it's radiated bleed time and now you've got the heating system reinstated just check for leaks but as you can see there's none there hopefully yours is the same and the job is done so hopefully you got no leaks you've got your heating system back up and running and i'm willing to bet you're surprised how easy that was to do if that helped you out hit the like button for me because that does help this video to reach more people who wouldn't have seen it otherwise and if you like diy content just like this make sure you're subscribed because i've got tons of it to come throughout 2022 and beyond there's a link to the trv and the bungs in the description so go grab those they're great bits of kit also check us out on instagram because i've got an instagram page now the diy guy i'll stick a few pictures and bits and bobs on there so you might want to give us a follow as always thanks for watching and i'll see you guys in the next one

Channel: The DIY Guy

Views: 1,713,184

Keywords: radiator, plumbing, thermostatic radiator valve, trv, diy, plumber, diy plumbing, plumbing basics, install a radiator, replace a lockshield valve, changing a lockshield valve, change a radiator without draining system, change a radiator valve without draining system, how to change a radiator valve, how to replace a radiator valve, how to replace a trv without draining system, how to replace a trv, how to change a lockshield valve for a trv, radiator valve replacement, lockshield valve

Id: o2Y9elh24wc

Length: 14min 53sec (893 seconds)

Published: Sat Apr 02 2022