It's often a good idea to latch the valve's lever in the manual position so that the valve is in mid position. Then when you drain down you don't get any nasty surprises when the valve is removed because all pipes to it should be fully drained.Another tip. I cut the old valve's 5 wires at the wiring centre to leave a 3 inch (approx.) piece of all the wires still connected to the block. Then when you come to wire up new valve you just undo each of the screws on the block one at a time, pull out the small bit of the old wire in the connection and put the wire of the same colour on new valve into it's correct connection. Can't go wrong.

A love Al, even if i'll never need to do what he is in his video is i'll still watch it!👍🏻

You sir, are a true gent and make even the difficult of jobs sound like a stroll in the park on a Sunday. God bless you young man! And thank you.

Thanks Alan, really useful video you uploaded. Good natured and set at a good pace. Understood easily thanks to you. Feel my valve needs replacing as keeps ticking and heating only trigger when hot water is on.

What a smart and nice man! great video!

Hi Al, as you say it can be beneficial to change the whole fitting as the problem may have been caused by a siezed valve spindle burning the motor out. Not everyone has the skill to test the actuator head to find a fault, so better for the DIY' er to change the lot. Nothing worse than fitting a new head to have it burn out 5 mins later. So always try to turn the valve spindle with your fingers first (Should turn easily 1/4 turn) if planning to just renew actuator.

Al. Thanks very much. Sincerely! I have forwarded the link to this video to a former customer of mine. Read on and you will understand why. The customer, ostensibly a "competent" DIY'er, called me to attend a faulty 3 port. No heat, no hot water. Controls, pump and (wall/cylinder) stats working OK. The cwst/f&e tanks and cylinder were all in the loft. What struck me was that the cover off the wiring box was already off, so alarm bells rung straight away. I multi meter tested the controls to check that they were switching on heat, hot water and both on demand and diagnosed that the valve was the cause of the fault. I initially thought that someone had been "tinkering" with the wires. I had to traipse across Sheffield to Rotherham, at rush hours end, after a long day on another job to diagnoses the fault. I stated that I could only get back at 7pm the next day. I called the customer at 6 pm, next day. Left voice mail as a courtesy. "I've been and bought the part, I'm on my way and running early. See you 6.30 to 6.45". Sat in van til 7.45. No one at home, no call from customer "please wait I'm running late". So, I turned off my phone and drove home. 3-4 hours of my time + fuel and 2 consecutive evenings where I could not say "nighty night" to my 5 year old son. I can only presume that the customer fixed it himself. I really hope that he watches all of your videos in future and doesn't waste any more of my time, ever, EVER again! I have not even received a call to say "thanks, I've fixed it myself" Wont hold my breath.

Thanks very much, your video's are invaluable ,😁👍👍👍

Excellent tutorial, no bull, just straight to point 👌

Thank you , very informative video

Thank you!

Very helpful video. I'm not a gas technician just watching videos for the lazy gas technicians who work at my place to know what they are doing and complaining about. Cheers mate

I did this job a couple of years ago but with no You Tube help,it went ok but I would have felt more confident if I’d seen your video first,thank you for posting this.

Hi awesome vid with this 3port valve can central heating water come into contact with domestic water

Thanks for the informative video. I have a Drayton 2port valve that is seizing and allowing water to pass as it doesn't shut fully. The motorhead is fine. My system is unvented. I have good understanding of plumbing and electrics and am competent with the basics. I have read that to work on unvented systems you have to be "G3" accredited. Does this apply if a homeowner just wants to replace a central heating zone valve or should I get a professional in? Also am I ok to reuse existing olives as the look like quite a job to get off? I noticed you seemed to reuse the existing ones, should they seal ok? Thanks.. and sorry for all the questions 🙂

i have a combi boiler a Keston C25, the zone motorized valve was broken in the system, thx to this video i replaced it myself, its a 2 port valve, was pretty easy to replace, just had to buy to wrenches to hold the valve , it was hard to remove the nuts. Before taking it off i was not sure what is actually sealing the water, but than i saw in your video the ring on the pipe, i have the same, also new ones came with the new valve but i could not remove those rings from the pipe and i did not want to force it so i just left them there, it not leaking. Then i found out the real issue, the valve was actually working fine, tough when i tested it off the pipe it closed the way to the water, but even with the new valve fitted the rads got hot even when the valve was closed, than i realised that the water pressure makes its way through the closed valve unless the motor is installed on it, cause that is forcing it closed, not its ok. The main issue was actually that another pipe above the valve was leaking and dropping water on the electrical connection shorting the motor and burnt the fuse in the main switch on the wall, so actually i could have replaced the motor only and fix the leak above, but anyway it was so easy to replace the valve now i a have a new one. question : do i have to do anything now, like bleeding the rads or something? the hot water is good, the rads get hot when the thermostat switches the valve and boiler on, this is a small apartment so i only have one zone for the whole apartment therefore only one valve for the whole heating system, so the system seems to be operational, what else do i have to do?

Thanks All !

Thanks for this. Top stuff

Hi Al great vid i may have to do this soon my question is when you drain down do i need to drain the cylinder down too ? Cheers Pat

Nice helpfull video Thanks

hi, great vids, im going to attempt this myself only thing is i checked the wiring and my original valve only has 4 wires blue, white, grey and yellow, the original is a Myson if that helps, if i buy a new one with 5 wires where do i put the 5th wire??

Hi Al. You say to refill your system but what's the best way to do this? Is it just switch the water back on, wait for the water to stop filling the system and bleed each individual radiator? What about the boiler, do you need to take any precautions to make sure that fills? What about preventing airlocks or how to remove them if you get one? Thanks!

When changing this valve would you recommend draining the heating obvs aswell as the entire hot water cylinder

Brilliant video. My heating stopped about a week ago I looked at the motorised valve and to begin with I found that the little manual over ride arm pushed along into the slot and the heating started to work, but now the arm is loose. I presume this means the valve is stuck. Is now the time to replace the whole thing?

Hi, I was wanting to move a mag filter near my boiler on the return of a vented system. I was wondering when I drain down the system could I just turn all the radiators off to save draining them or would that create air problems when I go to re fill?

Thanks for sharing. As well as the 3 port mid position valve I have a red 2 way grundfos valve looks like your green one. What is that?

I have just had a new consumer unit fitted to replace an old type fuse box.When the port valve comes into operation to switch hot water over to rads it is tripping out the electrics.I was warned that the new unit would be more sensitive to faults than the old fuse box.I am putting the port valve onto manual when the water is hot enough and it is working ok in that position.The water is heated by a coal fire/back boiler system.Any advice would be greatly appreciated.

Thanks for your video. I have a 3-way valve positioned at a level half way up the hot water cylinder. Therefore I assume I would have to drain the cylinder at least half way before removing the valve. (Shut off the ball valve in the cold water tank, and run taps?) Also turn off the cold feed to the central heating and drain out enough CH water to get below the level of the 3-way valve. Would this be correct?

Hi mate, Great video, I'm going to replace the exact one, the only trouble is the new one i have, cable won't reach the connection box, would it be OK to cut the cable and use thermal block connectors, many thanks gary

Hi, which position should the motor's switch be in? Should I put it in the manual, automatic, or mid position? Or will the motor do all that for me? Note that I found it in the mid position after I found the radiators were getting hot with the thermostat down whilst the system was heating the hot water tank on a timer. I had it on for 1.5hr which meant the central heating was on all that time during mild weather. Is it anything to do with the position of the switch on the motor? Appreciate your help.

nice man .good job

How much movement should there be in the actual valve? My motor had seized so was planning to replace as the valve can be easily turned by hand. However the valve only turns about 45 degrees (approx 1/8th of rotation) andsee in one of the comments it should be able to turn a quarter (90 degrees). Can you advise how much movement the valve should have as I’d like to know if it needs replaced as well as I can easily to the head, however to do the valve I’d get a plumber

Can you change a 3 port valve body without draining the system, meaning freezing the pipes?

Who is the authorized dealer in south east Asia ? Could you please send me any contact detail

I'm going to be doing this myself on my 2 port valve body this weekend. I notice you just undid the old nuts and left them and the little copper washer things on and reused them. The new valve body comes with new ones, I assume it's ok to just re-use the old ones then? From what I gather from your vid as long as they are done up tight they won't leak? Thanks Phil.

when replacing the valve do you need to drain both the hot water and central heating system, mine is a sundial Y plan system? thanks

Hey, another great vid and I need to do this process so before I fill up my house with water lol, I know you said to try and get the exact same fitting but I have an old system but have found something that looks the same. I put in a few numbers to check the part etc and it looks like the same. So my question is, as long as the diameter is the same and the same ports etc I can't go too far wrong, correct ?? I know the colours of the wires may be different but I will tackle the wiring at the same point. If it all looks different then I won't touch the wiring but I'm gonna need a new valve anyway. What do you think ??

I always take a pic of wires before removing anything. I'm no plumber or electrician and get my work signed off but I would like to know if those 3-way / 3 wire valves on Amazon are legal in the UK - given that the green/yellow is the "neutral", blue is "live" and brown is the other "live". I know exceptions have been made in multi-switch lighting circuits.

How often would you flush the system out and replace the inhibitor as routine? Thanks

RIght just done this job and i can hear the motor running now in the valve when I turn on the programmer. However, the boiler is still not firing up when calling for heating, but fires up fine when hot water is called? Wall thermostat is working fine :(

Hi, thanks for the video. When I turn the hot water on the boiler fires up no problem but when I turn the heating on the boiler doesnt start up. Would this be a problem with the valve? Thanks for your help.

Wow thanks very much for uploading this, my 3 way valve had failed and I watched your video where you advised to swap it over to manual and that has got us up and running and now . Ive subbed to your channel are you actually obey wun kenobi!

I had hot water but no heating, tried over riding manually by pulling the lever across, worked for 10-15 mins, off again, changed the valve every thing worked but once we turned the heating off, never came back on again, even the hot water had gone, boiler not responding anymore...could it be an air lock?

Quick question please guys, I have a 3-way directional unit but when I turn the heating on it seems to be heating up the hot water too. I've opened the directional valve silver cover to see that when I turn the heating on the mechanism is physically moving which it is but if I were to turn the water only on & not the heating the mechanism doesn't move at all. Does this indicate to a faulty directional valve unit ?

And remember to check your outlets. ab= flow from boiler/pump, a= heating, b= hotwater. Assuming it was fitted correctly in the first place that is.

Ive just changed the valve. However.. upon re filling the heating. What am i missing/doing wrong? I put the bleed key and undo, but theres no rush of water or rush of air.. just.. nothing. I presume ive missed something to get water back into the rads.

You said you prefer boss white and a lot of people don't. Do you mean as opposed to ptfe tape?

thank you I now have heat.I dont know if I will change the valve out myself but at least I might not get ripped off employing someone to do it for me.

Thank you for

Good video Al. So Al, how do you do this without draining the system?

I wish I worked for you.

Electric wires and water pipes all together at the same place ONLY IN THE UK.

al got no radiators working only one radiator upstairs still got hot water and all pipes around tank are hot

Legend!

Drain the system with 20 rads...Err I don't think so. Why do they not install 22mm isolation valves on either side of these replaceable items?

Hi, I need to replace this valve. Am I correct in saying the procedure is as follows: 1. Turn off water supply from mains outside the house. 2. Turn off electricity at mains (erring on the side of caution here) 3. Open taps on ground floor. 4. Open taps on first floor. 5. Then replace valve. 6. Then do 1-4 in reverse order? Thanks

hi.. where are you based?

You'd have been cheaper buying a 3 port body replacement kit (Honeywell 40003918-007) and a separate Powerhead 003 or synchron motor, than changing the entire body and head.

Con artists an overpriced dishonest plumbers an tht must hate this guy. Bless u Al com over to my house any time

junk