How a Zone Valve Works - Hot Water Heating

I had so many views on the video I did for "How a Hotwater Natural Gas Boiler Works" that I thought I would do a second video around the the zone valve in a hot water heating system. The zone valve is a electrical mechanical valve, with three main parts: the powerhead or motor, the mechanical valve itself and the end switch (microswitch).
The original video: • How a Hotwater Natural...

[@roseparini4202]

Awesome and much needed video! I am 66 y. o., widowed many years so in past have replaced pump, expansion tank etc on mu boiler. A few years ago replaced a micro switch on one of the valves and another one now needs either it or perhaps the valve motor. Your video has taught me how the boiler operates!!! And the component about the override switch was also super helpful because my toggle won't push freely all the way to the right so it might need the new motor. Your video was great in time and being so succinct!! Thank you so much for taking the time to do this! People like you are contributors to me being able to keep and stay in my home of 40 years!!!!!!

[@johntube2525]

This is a great explanation of how a Valve Assembly works. Thank you Andrew! I have clicked like and subscribed. Keep up the good work! I replaced just the valve assembly motor even though the old motor was turning, I thought maybe it is a weak motor and is not pushing the micro end switch all the way in. Also, it is way easier to replace just the motor. With new motor, I still had no damper opening, no circulation pump and no boiler fire up, even though the motor was doing it’s job. I had robbed the motor from a brand new complete zone valve assembly. With new motor on and POWER OFF, I then tested the old micro end switch for continuity and when pushing the button ALL THE WAY IN, I got continuity. I then tested the brand new micro end switch on the brand new zone valve assembly and noticed I got continuity with the BUTTON ONLY PUSHED ABOUT ½ WAY IN. I decided to take the NEW motor off again so I could access the micro end switch screws and proceeded to replace the old micro end switch with the new one, even though the old one had continuity. Once the new micro end switch was in place, I put the OLD MOTOR back in place and wired up everything. I turned my thermostat way up and then turned on the power to the boiler and Walla, damper motor turned, circulation pump came on and the boiler fired up. So it was a bad Micro end switch. That zone is working again with old motor and just a new micro end switch. Thanks again!

[@KH-ni9ht]

I was curious to understand about how radiant heat zone controls works, if fail and how to fix. This video has answer for each and every steps very clearly explained by the author and presented in an exemplary manner with steady voice. Any layman can understand the way he explained. My hats off to this very talented man. Look forward his expertise in other videos.

[@subhashkulkarni4689]

This was very helpful to know that the valve itself rarely fails, it is the box above that may have issues. I was able to fix mine where the temp was overshooting by 6-7 deg over the set point. After spraying oil (carefully) over the gears I was able to rotate them without sticking, thereby solving this issue I had with the retracting spring.

[@AndrewWorkshop]

+Subhash Kulkarni Interesting, the gears must have been sticking.

[@Muchkneadedmassage]

Thanks for a clear and easy to understand video. Being a visual learner, I especially appreciated that you took the zone valve apart.

[@danmccurry3810]

Thanks for making this detailed informational video on this subject. My mother in-law had issues with this for years. After watching your clip in about an hour I zeroed in on why and where the problem existed.

[@akusantafe]

Thank you for an outstanding video. Very clear and helpful. In my case, the end switch was sticking when it had been released by the motor-activated lever. That is, the lever releases pressure on the end switch, but end switch button remains depressed and hot water keeps flowing to radiators. This single video enabled me to understand all I had observed!

[@Stalled69]

Aku SantaFe how did u fix it? Mine is doing that too!!

[@delxiv]

Finally know how a zone valve works and how easy it is to troubleshoot. Great video and thank you!

[@corncrasy]

This video is 7 years old yet still very helpful. Thanks!

[@stevencote5786]

My bad. It's Alternating Current. Not Direct Current. But in the end. The mechanical motor is propelled by electron flow. Which is Electricity.

[@roseparini4202]

This is one of the very best videos on any type of repair on anything, not just boiler/valves. Your explanations that co-ordinate with each of the components inside the valve allow a through understanding of how a valve works by taking the time to take the valve apart and explain further. This was so great because it didn't leave questions in my mind! I can move forward with installing a new end switch and interim used your demo for overriding from an operational valve to the defunct one so that zone has heat while I wait for the part. I do have a question. If the motor has power to it how would one know if the motor is short of getting the little arm on it up far enough to touch the end switch? I'm almost certain its the end switch because we replaced it but it isn't working and the motor has power. We thought perhaps the micro switch was placed just a fraction off of its designated position (which doesn't seem likely because the screws indicate where it is positioned in order to get them screwed back in. The other question is this: When soldering the end switch to the wires the iron touched the corner of the switch casing and although it barely melted the casing if this could ruin the switch? When pushing the little rocker arm with a paper clip the switch works and caused the boiler to engage. This is what made me wonder if the switch works with artificially getting it to complete the circuit to the boiler then could it be that despite the working motor could the little arm attached to it not be rotating far enough around to touch the end switch? Is there a way to determine whether it is or not? Thank you so much! I am a retired widow and without doing most of my own repairs I would not be able to stay in my home! You tube videos are the best ever in providing free knowledge that makes all the difference!!! It is such a cool way of helping each other during these horrific economic times in our country!!! My warmest regards and gratitude!!! 1

[@paulrivet8254]

I'm glad I stumbled across your video. When I turn up the thermostat for my upstairs it wouldn't turn on the furnace and after watching your video I did some trouble shooting and it was my end switch that is the problem. Had you not took apart the zone valve I wound never had known about that switch unless I called the repairman. You sir have saved me some money so thank you very much.

[@AndrewWorkshop]

+Paul Rivet Glad it helped!

[@americafirst7676]

Good job explaining how a zone valve works only thing I would possibly add to this is why you have zones valves in the first place , only reason why I say that is because I had friends ask me why they have them when they have a circulator .

[@michaelpoczynek]

Thanks for making his video. I have replaced 4 out of 4 of these on my boiler. I would love to see what the wiring looks like at the boiler/controller end(s). 😀

[@omfgimgettingpissed]

Ok so I turned my room stats down below ambient room temp, I then went and checked the zone valve, the hammer had returned to the off position and the end switch was now visible. I clicked the end switch on and off a few times with a small plastic straw. I then returned to the room stats and raised the temp until above ambient room temp. I then went back to the zone valve and the hammer had fully depressed the end switch, the boiler had fired up and the pump engaged. Many thanks for this very well put together video, you have just saved me a small fortune calling out a plumber. If I have to eventually change the zone valve, I can do that myself and it will only cost £47 for the part. 👍🏼🍺

[@mamapoint4823]

I' and my kids have been without heat in northern mn for weeks because of something this simple that my landlord has failed to fix...or at least show me I could do this! THANK YOU!!!!!

[@herrprepper2070]

Much obliged! Our lower level zone valve went out when it was 29 below outside. I manually opened the valve per your excellent video.

[@jayvee0404]

An excellent video clearly explaining everything so the layman can understand. This has been very helpful to me, so thank you so much Andrew for taking the time to do this.

[@mehrdadkeshmiri2337]

Thank you Andrew for your detailed explanation. That helped me to understand what was wrong with my valve system, and replace the faulty valve. Very useful video. Thanks.

[@T-Bone5160]

Hey, Andrew W "boss man." You nailed it for me. the "N" switch. 9:40-10:20 and a minor mention before that. That is the issue for me. Valve operating in response to the call for heat but boiler not igniting. Much appreciation. Blessings to you and your household.

[@brybrooks3648]

9 years old video cleared my confusion! The Best.

[@vmeas]

Thanks Andrew for giving me the confident to tackle on this repair myself. My valves should be here tomorrow. I have 1 bad vale that is completed corroded, which I will need professional help to replace. The other one is the end switch is not making the contact, valve will open, but not power to the boiler. Hopefully just replacing the motor will fix the problem. Thanks.

[@KatherineStage]

Thank you for helping me better understand the ins and outs of these. Very helpful!

[@richardbolz5303]

This was an outstanding demonstration project. It was well done and informative. Did not know about the end switch closing to allow the burner to com on.

[@joellebodin8740]

You are awesome! Thank you for taking what seems complex and breaking it down to make it SUPER easy to understand each little piece. I appreciate it.

[@franklindiaz4411]

Great job Andrew w. I really appreciate when people take their own time to make videos like this one .. many thanks comrade.

[@davidparker7696]

Great video. Clear, concise. I think you've addressed the exact problems I'm having with my system. Thanks!

[@WBIGTVBuffalo]

With my Honeywell unit V8043F, the end switch is designed to not activate if the unit is manually set to on. So for that circuit to heat, at least one other zone has to have a call for heat.

[@edrogers9530]

Very informative video. Been troubleshooting our 4 zone system. 3 out of 4 are good. I assumed it was a T stat but upon further testing. Isolated it to the powerhead. Just like you show in your vid about not hitting the end switch. Ours isn't either. The lever gears are chewed up and stripped. Trying to manually turn it on is futile. Its like its damaged. Even when I turn of the T stat, the manual turn on lever flops around. I have a new powerhead on the way. Hoping that solves the issue. The motors are brushless. Seen a few videos and they do mention that. Well done.

[@corazonplummer3388]

Very helpful video Andrew, thanks for making the time to make this video.

[@stevemittelman4068]

What an excellent presentation. Well done! Thank you so much, Andrew.

[@thesteadyanchor]

Just viewed your video, aside the lack of light it was awesome. Extremely helpful

[@timjorden8329]

Very helpful I had one zone not working too good. I could hear it opening when the thermostat was turned up but the boiler didn’t turn on and the circulation pump wasn’t going.

[@hpdavid1]

Andrew, great video and explanation of zone valves, much appreciated

[@sylvi73]

You saved me from freezing tonight!

[@onebadsavage26]

In one short video you sorted all my issues in wiring my new heating system. Thanks

[@tacrewgirl]

Wow, great video. Answers a lot of my questions. I think this is what is wrong with my heat.

[@StocksignsVideos]

Great video, Andrew. It really helped me out I owe you some kroketten next time I see you

[@jhaanda]

awesome video! helped me troubleshoot the failing valve

[@배성훈-v2s]

Thank you for a great video. First time turned my boiler after replacing the chamber blanket. and i put an old fassioned thermostat it works. But the other zone i put a battery powered used thermostat so my loom is cold. I will try as you demonstrating.

[@johnstewart8613]

Great explanation. Thanks for doing this.

[@Kingdom0324]

Thanks for the video. I was having trouble in my hydraulics course and didnt u derstand how an end switch works. Thanks for clarifying.

[@cleosuperone8879]

Amazing explanation. Great video. Thank you

[@brianmahoney154]

The motor is a shaded pole motor. They are used in bathroom fans too. Most motors would over amp and pop the fuse if they locked up like a zone valve motor does. But a shaded pole motor doesn't care.

[@allenwang7792]

a wonderful video explains the mechanism well.

[@jakev5408]

when i turn my thermostat off the heater (water furnace)continue to run hot, could it be that switch stuck on or completeing the circuit?

[@andresoropeza2084]

You are an absolute godsend, thank you sir!

[@1lilsosa]

Really well explained, thank you for the information I needed to help diag my heating issue.

[@rcdesmond]

I Agree with everyone that commented on how well this video is done.

[@NickMango]

This video just solved a more than 3 year old problem I’ve had with my oil burner heat. Thank you 🎉🎉 happy to be the 1000th Like too 👍

[@rchrdhzl]

I am learning that Zone valves are installed on the return as opposed to the supply where you have them(?). lower temps preserve the units longer...allegedly.

[@katherinesmith9602]

thanks i would like more of these

[@impsquared]

6:26 yes it is a check valve, flow in one direction, in the direction of the arrow!

[@robertjohnson2398]

excellent video, very educational and real time practical! thanks

[@rhysgeese1424]

Thanks for this great demo!

[@StevenChmielnicki]

Excellent work. Thank you.

[@to254]

Superb. You explained it very clearly .Thanks.

[@HipshotA]

Thanks very much. Very easy to follow and extremely helpful.

[@Pinoyphilly]

Andrew: which is better a normally open ZV or a normally closed ZV? Thanks. Video very informative. It could have been better if you have additional lights to illuminate the side of the ZVs

[@operatoroperator7443]

It's not about what's better, it's about what your system calls for. If you install the wrong one the boiler will run opposite of what it should. Just google the numbers on the switch so you can replace the switch with the proper part.

[@skippymud]

Awesome vid, Andrew. Thanks!

[@MrCiti211]

Thank you very much for advice and it truly helps a lot.. My valve is on auto when I crank the thermostat way up.. I manually place the valve button on but later on when shut my thermostat on off mode.. Then valve goes on the auto button then it never comes back on the valve on side even though it I turn the heat way up..

[@AndrewWorkshop]

+Lhagyal Serdok Sounds like the motorhead is bad, they are easy to change. Just get another valve and change it out. Not sure if they sell the motor on it's own so you might need to buy the whole valve and take the motor off. I would suggest before you do that tho to test the connection to make sure you are getting power to the valve before buying a new one.

[@miked2560]

Fantastic video!

[@theworldviewer]

Excellent instructional. I do have a question. The heating system was installed in my house back in 1989 when I added a second floor to my home and converted from forced air heat to baseboard hot water. We have always thought the heating system in our home was not “just right” and had the furnace on longer than it should to reach set temperature. The plumber installed three zones and all of the Honeywell valves are installed with the manual lever at the top and the arrow on the brass pipe is pointing towards the boiler in the opposite direction of the flow of water. Not knowing any better, I replaced a bad zone valve myself back in 2009 and installed it the same way. I’m thinking that the electronics are operating a ball valve and it might have a slight restriction for water flow in the wrong direction. I would appreciate your advice or from any qualified plumber. I have one valve that has been sticking in open position last heat season and am going to replace it - with the arrow pointing in the correct direction. I’m thinking that I should replace the other two in the arrow pointing up.

[@bigpardner]

Manual switch- when you manually open a valve as you do at 3:37, you mechanically open the pipe, and you send a signal to the boiler as would occur when the valve motor itself were activated and opened the pipe and moved the micro switch--- or not? I'm not sure. I have opened the valves in the past to purge air but I believe I always had the power to the boiler shut down.

[@andrewcpham]

Good stuff Andrew! My valve ball broke off so I removed it and now getting heat into my air handler. Question is why can’t I just leave it manually open without ball. Meaning I will always have hot water in my heating coil and when thermostat calls for heat the blower will blow and I’ll have heat. Seems I don’t really need the valve plate with the black ball. In summer I can just Close water switch to unit.

[@batoulbaterdouk4604]

Really appreciate the info!!!

[@samvivi7]

very clear and concise thank you!

[@michaelc1042]

Thank you for a very clear explanation of how a zone valve works, very much appreciated! Taking the controller apart took the mystery out of if for me; nice work!! QQ: do you have a video on how to wire up a zone to a controller board? I have a 6 zone controller board with relay switches. Each zone has it's own pump except one pump is used for two zones and I have two controller valves wired together for this one pump (return side plumbing). I disconnected the wiring to each zone and now I don't know how to wire the zones back the way they were. I have 4 wires coming out of each controller valve (2 black and 2 red). I remember one of the red wires from each controller were connected and the other red wire from each of the controllers were connected into one but I don't know where each of those reds should connect to (controller? 24vac?). Do the two blacks go directly to the 24vac transformer? I use a simple mercury thermostat and wondering if that should be wired directly to T terminals on the board, or should it act as a 24v switch so the controllers get 24vac when thermostat calls for heat? Sorry for the confusion, but if you did a wiring video and point me to it that would be a great help. Thank you!

[@paulp757]

Great video. Very informative. Nicely done. Thank you!

[@marksmith9989]

you answered all my questions! what's the voltage to test for (24VAC), how does the circulator and furnace come on (the end switch). Thank you!

[@janessagrant]

Very well done. Thank You.

[@vinces8974]

Very well explained thank you

[@juangarza5037]

Thankyou your video was very helpful..Great job on explaining the procedure

[@simonpatterson8798]

OMG, THANK YOU! That bypass is going to save my ass!

[@MrLuvOldies]

Thank you. Very Good Information.

[@davetobias3788]

Excellent presentation, thank you

[@angelaburdon9128]

Great video. Very helpful. Thank you so much!

[@venusfan]

My system looks just like that with 3 zones. Basement, 1st and 2nd floor. 7 years ago I asked the technician to make the basement connect to the 1st floor thermostat since I didn’t go down there that much. Fast forward now and I have an In law down there and temperature wise when it’s 72 degrees on the 1st floor it’s 65 degrees in the basement. She used an electric heater last winter and bill is crazy. I now want to connect that basement thermostat again so it can regulate the heat in the basement because the furnace is gas and a lot cheaper than electricity. I remember when I asked the technician to switch it the entire process took less than 30 seconds so I would like to find out how to do it myself. Any help would be greatly appreciated.

[@3158030Michael]

Thats was a great video! Thank you so much for your help!!!

[@jreyes7977]

Very helpful video. Thanks.

[@hugedabs5827]

Great explanation… but I can’t believe those solder joints made the video. Wiping the joints makes the install look so much better. 😂

[@johnjohn-ne8fw]

Nicely done ✅

[@lx2077bob26]

Excellent video....well done

[@rudyparra8461]

Great video, thank you for sharing the knowledge!

[@thejuckster]

THANK YOU!!! Great explanation.

[@speedster4410]

Great video. Very helpful 👍 kudos

[@menswearhous]

does it matter if one of my zone valves looks like it is upside down? the arrow is pointed in the right direction though.

[@theworldviewer]

I have the same question. The plumber who installed my heating system has the manual open/close lever at the top and the arrow on the pipe section is pointing in the towards the boiler, although I know that the hot water is being circulated in the correct direction.

[@angeldejesus65]

Great video.

[@omfgimgettingpissed]

Top video!! Gonna take this apart and see if I have a switch problem. Pipes are hot but the boiler isn't switching on and pump isn't engaging. Hope it's just the little switch not getting hit. If so I'll replace the whole powerhead. Thanks for the great video.

[@felixlaboy1453]

Great video buddy. May I ask ? I have a 2 zone system I notice this winter that I only get heat upstairs only if the heat on the first floor is on. I have a nest upstairs and downstairs. Please advice. Thanks for any help

[@mikeclay567]

very clear explanation thanks

[@jayram670]

Amazing! Thank you

[@garyha2650]

Where can I find a purely mechanical version? Unlike a car thermostat which opens (physically) on rise for water flow to the radiator for cooling, it would be close on rise. On top of that I'd like it to be adjustable. A friend wants to build a boiler using the campfire at a gold claim and I think automatic regulation from such a valve would reduce frustrations.

[@bapt1]

Thanks, andy. Incredibly useful. Saved me calling out a plumber. Much appreciated

[@danamueller4695]

Thank you! Very helpful.

[@MsHotGraphics]

Hello Andrew, Thank you for the video! Please answer my questions We have a condenser boiler. Just recently the water valve was replaced. Now one of the zones remain open (heat cannot turn off) and cannot be controlled by the thermostat. Is there a way to shut the zone entirely off? I actually don’t need heat for this zone. Replacing the water valve change the pressure to these zones and so damage the zone?

[@kingsburge8309]

That's really helpful and clear. Thanks a lot

[@L110508]

Hello Andrew, can you please answer 2 questions : -My system is gas boiler with some zone valves. The hot water tank is also controlled by a zone valve. When bleeding or purging the system, do I need to bleed the hot water tank's zone too? - To bleed a zone, I was told to just shut the valve on the pipe with the zone valve, connect a garden hose to the drain, manually turn on the zone valve, and open the drain. When doing this, do I only manually turn on one zone valve that I'm bleeding, or I have to let another zone on too to reduce the pressure (so bleeding one zone and turn on another zone without bleeding at the same time)?. Thank you.

[@jaybee1892]

Amazing video pal......but i have a huge problem!!!! My system is so backwards, my zone valves are actually in the apartments and not in the boiler room. So how do i know which valve goes to the floor im trying to drain.

[@mava5634]

very well explained

[@christakispaphitis635]

Where should the switch at the bottom usually be positioned ?. It clicks if pushed all the wall to the left. Is that where it should be, or slightly right ?