HOW TO PULL A VACUUM - Apprentices - Quick TRV change - Plumbing Tips

if I understood it right, you need to close all bypass valves in all radiators, right?

Can you use a wet vac once the system is bunged?

This is great however, is there a video available on how to change a TRV on an upstairs radiator (the tank and pump are downstairs) on a pressurised system please?

Good to see. If you don’t have time to use ptfe, prepare the new valve with white paste in advance

Makita wet/dry vac is amazing for jobs like this

I’ve just bought a bung kit, but on the back of packaging it says “ Do not disconnect more than one section of the system at a time (eg one two-way connection but NOT one three-way connection). If I bung a system with a three way motorised valve do I risk damaging the system or not being to be able to pull a vacuum? Please help.

I set my house on fire doing that

"Theres no time to put PTFE" - says the man who picked up the valve that had sat next to him for the duration of the video.

As if this person still has VHS tapes 'on display'.

Great video as always. After watching your videos in the past, I thought I had a combi boiler. Well we had the engineer in for service and he told me it is a Condenser Boiler which has a water tank for the hot water in the airing cupboard. On this video you say a pressurise system with high pressure relief valve (is that the same as PRV), and filling loop, would this be a condenser boiler, as you also mention combi in the same sentence. Thanks for any info, brilliant video. Stay safe you and yours.

I tried this and it didn't work for me it just wouldn't vac. Had to drain down in the end.

Realised as you changed the valve I was holding my breath! 🙈

Do you have to turn the boiler off?

I am more of an Engineer than a full-time Plumber but I have done tricks like this in the past, one thing that should be thought about and could catch someone out is "Fitting Stop Depth" in the video, the valve was swapped over but the existing nuts and olives were utilized. This is fine to do if the new fitting has a deeper or equal stop depth, however, get a new fitting with a shallower stop depth and the pipe will not travel into the fitting far enough for the olive to seat, sometimes if the olive is not too over-compressed it may just slip up the pipe IF you are very lucky.
If you are unlucky you have either got to try and bung the end with a small rag hacksaw a tiny bit of the pipe away or better still use an olive cutting tool and re-install a new olive.

I tend to freeze the pipes and stick isolation valves in rather than drain down

you're a true legend you ✌🏼 bring so much sense when my brain farts. good man.

Can you use these plugs if both trvs are turn off and the rad it already off the wall?

Youre allowed to keep the original nut and olive?!

Anf then u find out the valve is different and the olives are to far back lol!! And bung falls out 🤣🤣🤣🤣

Hi mate, I "love" you're videos? Where r u located?

I was waiting for to get your G tech out!

That Was a good Clint Eastwood impression 😁

Excellent demo mate. From a nearly qualified Plumber.

I changed a trv and lockshield on a Friday night... Never had to do it before, pressurised system, don't know what I did wrong but the hot black water exploded into my face! Massive fountain of water came out.. I ran downstairs to shut the stop tap and completed the job with new olives... I still don't fully understand the difference between pressurised.. apart from it being a combi boiler which should act as the bung but what do I do from the valve I'm changing? And with f & E systems I'm yet to take on... Got to do a 2port soon but keep looking for tips on how to do it.. without bungs..
I was just going to tie the ballcock up and drain from lowest point(smallest rad) turn boiler off and carry out the work... Be great to see a video from start to finish using a universal method..
Cheers for your vids Jim! Top stuff, learnt alot from your channel

The following may add a few handy techniques. Get yourself a simple monkey wrench (not a pipe wrench) to support the valve. The open jaws fits over the valve body from the side. The centre line of the valve passes through the open jaws of the wrench. If the system is heated up to hand hot (about 50C) before fitting the bungs (or draining out a sealed system to zero pressure), then as it cools over the next ten minutes it creates a vacuum that in many cases sucks air in, thus preventing all water leaks. Also use a pair of smaller grips to (carefully) remove some paint from below the nut on the tail. This guarantees the nut will retract. To remove the valve, support it with the monkey wrench to save twisting the tail; release the nut next to the rad half a turn and tighten; then do the other nut likewise (for this one the valve need not be supported), then undo each 1/4 turn before fully undoing both. See if there is some upwards movement in the rad from the end with the valve to be changed. The other tail needs to be flexible when using this method. If so, the procedure is to hold the new valve in one hand, lift the rad (& old valve) 1/2" to clear the tail; pop off the old valve, push on the new one, and lower it back taking care to allow the new valve to sit over the tail without damaging same, or trapping fingers. When tightening the valve nut next to the rad use the monkey wrench again to support the valve. I also use a small amount of gas thread paste as sealant and lubricant on the cone faces of the valve pipe sockets and two small dabs on the valve threads to help the nuts tighten. HTH

Good tip and vid. I do this to quickly cut a valve onto pipework too.....but yeah, the heart thumps:))
Good job that pipe dropped into the floor to enable this type of valve to come off easily though, haha.

"As you can see, no time for PTFE " code for "Bollox! Just realised I forgot to put the PTFE on the threads before taking the old valve off...better say this so the customer thinks its deliberate". Well saved! ;-p

People, please don't use the PRV in the Combi to drop out the pressure, use a drain tap, the clue is in the name, drain tap! Got some crud stuck in the PRV and your customer, and boiler warranty service engineer (eg me) will not thank you for it!! ;-)

Can you cut in a magnaclean doing this?

Good to know. Did you change the TVR for a lock shield because the TVR was on the return instead of the flow?

Question for Mr PlumberParts: The black tank in the loft you bunged up. Does this tank service the hot water system as well? I have the same tank in my loft, and found the lid had been knocked off. To my horror I found a load of dead mice decomposed, floating in the water. I have no idea how long they had been in there and no idea if the tank itself feeds my hot taps, and in turn my bath water. I'm hoping the tank only feeds the radiators. The water I removed when cleaning the tank was black as anything. My boiler feeds the heating system and hot water system. Thanks for any advice given. ;)

It worked for me

get a plumb tub,it goes round the pipe better than towels

freeze the damn bottom pipe!!

Where's your wet vac lol

I bunged my primatic system, then someone told me I could of crushed the hot water cylinder with the vacuum. It did work though!

Jimbo does THE BEST Vids on the interwebs bar none.
So there.

I would have had the twat changed by 5 min

This is where you learn cross threading as well

at 8.00 are you talking about releasing the system pressure at the prv? sod that, never release a system by the PRV in the boiler, you're asking for trouble, bloody things never seal after you open them, and you can spend the next 2 hours struggling to the prv out. like on the WB cdi, horrible hand scratchers trying to get the spring clip out.

I always turn the trv or lock shield away from the rad and run into bucket or bag until it stops or bungs

How you doing mince where did you get the bung from

Thanks to this video my Dyson and I have been happily married ever since!

Wish I had watched this first and heeded the warning..

Hi buddy is there a bung out there that can actually fit in those cold feed tank connectors with the nicks around it inside. What else could you use

The best plumbing accessory in my van is a cat litter tray bought from the local Pound shop. It's shallow enough and wide enough to slot under any radiator and catch all the water. Good video, thanks for sharing.

a 22mm pushfit cap?

You should change existing nuts in my opinion

Put a bung in here then you put a bung down there then you go down and loosen this bung then take it out. Put the bung back in then tighten up this bung. Don't forget to take out the bungs when your done.