Electro-Plumbing Repair… of my home heat zones that won’t heat although the boiler is running fine!! 

I like how the plumber decided that the valves must be as close to the wall as possible, so that you need a special screwdriver to open them, instead of anywhere the the 3-4 foot of space between the valves and the boiler

Telling an electrical engineer they can't do something is like questioning a wizard's power.

As someone that does commercial HVAC controls for a living, it was interesting seeing you work through this problem.

As someone who has worked on everything from dehumidifiers to industrial boilers and refrigeration, I can say he missed his calling. Fantastic job again by Electroboom.

7:48 Amazing, resoldering a disconnect by running high voltage through the circuit!

the short circuit path is probably there in case all of the valves close, so you don't get a huge pressure spike and the water can continue to flow

My father and grandfather are electrical engineers and I can relate to the hierarchy, literally every problem is fixed by them

HVAC tech working on EE degree here, love the videos. This one brought me back to early days of my apprenticeship where I had to figure out the same issues. Having the nest controller makes things so much nicer

"Higher voltage is potentially more dangerous" this is the highly scientific and educational content that I've watched years of electroboom for. I wish they taught wisdom like this in schools.

I love how plumbing jumped to rocket science instantly 😂

I love how he always injures himself or other devices for our entertainment safely. A good man.

A word from the wise (and experienced). Honeywell zone valves are quite troublesome. I've had the gear on the motor strip out because it's made of soft material, the motors themselves get weak and wont go far enough to set the end switch. I use caleffi now and haven't had any more issues or callbacks. The actuator units have a lever that releases them from the body without opening the system. Honeywell has two small screws deep inside that make it tougher to change. Caleffi has a higher cv( flow ) rate

I love these kinds of videos, where he fixes stuff

8:57 "what are you burning?!?" -Medhi's family every day

This is so interesting my friend. How your investigation drove you to the reason why your AC motors failed at the first place. That s terrific!

Dear Mehdi, thank you for making these videos. I've learned so much in electrical engineering from your videos, while having a laugh from your content. Your content unironically makes my job in engineering easier.

As a mechanical designer, I have to admit: Electrical engineering is often basically some kind of sorcery to me. I mean... I get how a lightbulb works... but that's basically it.

Isn't it fun when something like this breaks down? You get all the fun of debugging an issue with an at this point pretty complicated device, all while dealing with the frustration of your heating or whatever other important thing not working...

Very cool. I'm an hvac tech ...ive never tore apart a zone valve that far. I fix these things all the time but still learned something today. Cool.

Every single mechanical engineer who watched his video is mad now. We are mad.

Whenever I see a big boiler, I always wonder how compact you could get it without taking away functionality. Then I realise that keeping it big and spread out is pretty key to keeping it easily repairable.

"WHAT ARE YOU BURNING?" Actually made my day, keep up the great work, iheMd!

Even with the voltage dropping when all motors are running, these motors would also work fine at 22VAC you could still drop the voltage from 31V to 27V, then a single motor would at least only get ~25-26V instead of 29-30

This was one of the best videos ive seen from you. Honestly really awesome to learn about every day powerpixies, that you normally wouldnt know about.

Fully agree, electrical engineers are on the top! ..we have unlimited access to black magic... 👀

This was actually fascinating, I'm finding your home electrical DIY videos to be excellent.

6:50 When he wet his skin to see if he would feel anything then he screamed in a British accent😂😭

I Love you mehdi! I designed particle accelerator electronics for 4 years, and me and my colleagues would watch your videos for inspiration. For example your Jakobs ladder was used as a 1000V power supply for a mock up injection kicker for ISIS Neutron and Muon Source in Rutherford. Keep up the good work, you might be helping more than you know.

glad to see the mech engineer trolling goes across the Atlantic ocean :')

I have the same kind of setup in my house except it's from the 80s and with only two zones, I had to replace the transformer and I pretty much ditched all the old electronics to make my own, now each zone is on a relay controlled by Home Assistant and I made my own thermostats powered by an ESP32. All the issues I had before were electrical too!

These videos are more entertaining than i’d ever have expected! Came here for a patio heater comparison and now I think i’ll stay a while.

The casual "What are you burning?" killed me lmfao

“Interesting how this plumbing problem turned out to be electrical” Sounds like whatever discipline of engineering that normally does HVAC did their job right, I wonder which types of engineers those are 🤔

As a plumber myself, Mehdi actually got most of the stuff right, just wandering who the hell did those pipes, they look so unorganized to me.

2:37 Mehdi is so Canadian 🇨🇦 🍁- “… and nothin’ aye?” 😂😂😂

9:00 Was the most genuine reaction I have seen from you yet, Mr. Explosion! Priceless!

That is an impressive heating system. I feel like a cave man with my propane furnace

I love how entertaining he makes these videos. Truly one of a kind channel. Mehdi makes learning fun. ❤️

Hi Medi, I’m a commercial engineer and I do a lot of pipework design - Re the pipework: The installer has tried to create a basic low loss header but (for many reasons) the primary pipework appears to be undersized and the connections for flow and return are too close together. Also there should be a by-pass between the circulator and the zone valves. I could write an essay on the correct way to do it… but if it’s working, please don’t start re-plumbing it! 😂😂😂

at 10:29 I'm like, "that is a stupid design". A few seconds later I was glad to hear you thought so too

As an offended Mechanical Engineer, I'm pleased to see that the problem was electrical as usual.

As an electrical engineer -- I feel validated ;)

I start getting anxiety as soon as the cover comes off and the more dangerous parts start getting yanked around. I know it's intentional, but it still gets me

Mehdi: Electrical engineers are at the top of the hierarchy, plumbers are at the bottom Mehdi two seconds later: *Points to plumbing* “I don’t know what this magical device is” 💀

It would be awesome to watch Mehdi fix the underlying issues that caused this problems. Run a dedicated 15 Amp line in the walls replace the transformer with a power regulator, or alternatively completely over engineer a system from the thermometers to the valves changing the signal to digital or at least DC

8:54 I had to laugh internally when I saw it smoking and Mehdi didn't notice ;) The angry (not scared at all) response to the smoke: "What are you burning?!?" (with a "Why do you allow yourself to burn?!?" between the lines)

At 5:58 get ready for some good Electroboom style jumpscare...!!

7:54 "and they say high voltage is bad" got me laugh soo hard

You know, I took an electrical engineering final yesterday, and it was nowhere near as fun as this channel

I love slowing down unexepected events to see if people were expecting them. 5:50 was completely genuine

I had this exact problem at my parents house a while back. The motors ran really really hot when they were on and a couple wouldn't work at all... Now I know why. Thanks for sharing your findings (also as an EE myself I died with the MechE joke...uh I mean fact)

Electrical engineers are basically plumbers... gotta make sure everything is flowing, no leaks, and if something breaks there's going to be a lot of damage to your house.

I never knew watching someone's frustrations could be so rewarding. Lol. Thanks for that , and the belly laughs too. Much love. God bless 🙏

10:58 This system resets itself to a known state; all valves automatically close completely upon loss of power, it's not possible to end up half-open. Using D/C motors and limit switches in the "closed" position could do the same, but then you need more I/O pins on the controller ($$), more switches ($), a decent power supply instead of just a cheap transformer ($$), more code to handle the "closed" switches (which means more potential bugs & more programming $$$$$)... It's the cheapest system that gets the job done and mostly doesn't fail before the warranty expires. Looks like a good engineering job to me! :D

Every video on this channel makes me remember that day when I was putting fire safety pallets into sockets in a school and got shocked doing this in front of a whole class. Electroboom is the same idea, but the scale is way up.

Absolutely one of the best teachers I’ve ever had

I mean, rocket science is basically plumbing explosions, so I think having plumbing and rocket science on the same level seems fair...

Watching your near misses helps calm me while I do simple electrical tasks around the house. As long as I verify the circuit is dead and be mindful of the potential of injury I feel much more confident I won't burn the house down.

Crazy to me how far your production value has come, been watching for years, super impressive. Best of luck to you!

You are one of my most favorite RU-vidrs. You showcase a brilliant combination of humor/ comedy with how-to knowledge. ⭐😇

Fail safe valves, what a concept! This design always uses the full travel of the valve and is very reliable on the 'wet' side. The proportional valves tend to be much less reliable, especially if the control system does not have routines that use the full travel regularly. As a former electronics engineer, who used (amoungst other things) to maintain the control system in a glasshouse comples with over 120 indiviual climate controlled compartments, I know a fair amount about these valves and their failure modes. Most of my callouts were to find that the control system was fine, but there was a mechanical problem, or that the control gear (the electricians responsibilty) was at fault. One proportional valve design that I liked, but was let down by a poor control board design, used a solenoid to pull the valve open, with the coil being phase angle controlled. The response was very non linear, but we had flow and return temperature sensors, so the non linearity would be taken out by the PID loop.

Maybe they just want the valves to close by themselves when you have a power outage, kinda like a fire door that is normally held open by an electro magnet ?

I love the timing ! Motor : .... [ just smoking for no available reasons... ] Medhi : WHAT ARE YOU BURNING !

I salute to this guy because he puts himself through pain and more pain and might get shocked multiple times just for us to learn things I salute to this guy

1:12 as a mechanical engineer my cold steel heart feels hurt

I really loved this video. Troubleshooting, fixing, explaining... felt like a mystery puzzle and I loved it.

I absolutely give plumbers a lot of credit. That is not easy work, and not fun either. I have a lot of respect for what they do (some, not all)

I like how they put the electrical box underneath the pipes too. Hopefully one of the pipes don't bust or start leaking right over it!

I think a follow up fixing/upgrading the power supply to run a constant 24v would be pretty cool

GreatScott is yelling at the screen at 11:54 for using those nuts instead of Wago blocks

The power cord cut in half killed me😂😂😂

The added complexity of something that used to be simple just furthers my need to live in a cave.

I work at a motor company. I've heard a bit of an urban legend that once, many years ago, there was a tiny strand of copper causing a short that stopped a motor from functioning. The fix? Shock the sh*t out it and burn out the short. Maybe that's what happened to you? Who knows

*looks in horror at wire plugged into 110VAC socket with bare wire nuts dangling in the air*

I could watch this man burn sh*t all day. The best (and funniest) education.

The "short-circuit" is the correct way to plumb that boiler. It is called primary-secondary pumping\piping. There are two circulator pumps. The primary pump circulates water through the boiler's heat exchanger. The secondary pump circulates the water through each of your zones for heating. This primary pump is actually located on the inside of your combi boiler. What I did notice is that the zone valves are not on the correct end of the zone piping. Zone valves should be installed on the return side of the piping so as to not to cause water hammer when the zones shut. Because the pump is creating head pressure and pumping into the zone valves, there will be a spike of pressure when the valves shut from the head pressure of the pump. This can result in a knocking noise whenever any of your zones shut. I would recommend moving the zone valves to the return side of the zones if possible. The voltage you are getting from the power supply should not really hurt those motors too much. Its pretty much a nominal voltage difference from what the motors are rated for. Most zone valve panels like the one you have output 27-26VAC to the valves. All the end switches on each zone valve are usually wired in parallel to the T-T (AKA thermostat) terminals on the boiler signaling the boiler to run. Each thermostat makes and breaks the 24V power going to each of the corresponding zone valve motors by disconnecting one leg coming from the secondary side of the transformer. If you continue to burn out that same motor I would recommend replacing the valve body and not just the motor. Usually what happens is mechanical resistance occurs at the valve stem over time from scale/buildup inside the valve. This scale/buildup will cause the motor to prematurely wear out over time. This advice is coming from a professional mechanical contractor/HVAC tech with 12yrs experience with hydronic/steam heating. Hope this helps you out.

dam, this is one of few videos that despite being 14mins long, finished in seconds.

2:00 Seems fair. Rocket science does involve a lot of extreme plumbing after all.

damn the overlay at 9:21 tricked me real well, you can for sure leave it like that !

2:00 This setup is a passive mixer; it reduces/balances temparature by joining the forerun and backrun of the loop at some point. Most of the time, there's also a reduction inside the plumbing where the two pipes join to reduce flow rate.

I love this rivality between mechanical and electrical engeneers !

Loved this Mehdi, really happy with all of these home DIY repair videos that just extend the EE knowledge to other areas. Great stuff. Thanks for encouraging me to repair things and to understand complex systems.

As an electrical engineering student, I absolutely agree with that dominance hierarchy.

Never forget, rocket science is just plumbing with extra physics involved

The pipework arrangement is based off what's called a Low Loss Header. I'm always amazed how folk in North America are so amazed by combi boilers. Viessmann and such have been around for many years in the UK. I've been to Viessmann's HQ in Germany for training courses too.

the electrical box at the end was the cherry on the pie. Can I say that I loved to see the horror?

11:09 24VDC 60HZ *laughs*

Fixed my landlord's A/C unit, a wire came loose that carried 30 VAC. Thanks to this video, I took a chance with my multimeter to mess around with 30 VAC and re-established the connection. Otherwise I'd would not have taken that opportunity and they'd be down $$150-400 calling a repair guy. Thanks Medhi. Not an electrical engineer. Studied chemical with a specialty in in biochemistry and some background in voltaics due the nature of my current work.

please release a short or a 2nd channel video fixing the plumber wiring!

The "shorted" hot water pipe is a bypass. It mixes super hot water from furnace with cold water. This way your radiators are safe to touch. You can think about this like voltage divider. Ofter there is a valve working like potentiometer so you can dial up output temperature.

THE MOTORS ARE AMAZING! 12:00

The switch in the valve is a "call for heat" signal to the boiler when the valve is open, so as long as the valve and it's corresponding thermostat/timer are both "calling for heat" then the boiler will fire up.

The bypass/short circuit path has a pressure relief valve in it. In case the water gets very hot and the syatem pressure increases, the bypass valve opens to inlet.

I suppose the motor fight against the spring and button all the time to have a fail-safe setup. If the power is lost or a motor dies, all valves close.

Letting an electrical engineer unsupervised will either result in fire or black magics, there is no other option

The "short circuit" Is what is called primary secondary piping. This piping arrangement decouples the flow rates from the boiler pump and the zone pump. You can override the zone valves with the little levers protruding from the side of the zone valves. Your zones have no flow valves and you do not have a variable speed pump to maintain pressure. In other words if all the zone valves are open the water will take the path of least resistance. add flow valves to each zone return...set the variable speed pump for 8 psi...open one zone at a time and adjust flow valve to obtain a 20 degree delta T. None of the trades you mentioned do this type of work properly. What you need is an HVAC hydronic tech. We are very few in the US but very plentiful in Europe.

when Mehdi does anything sudden I always flinch, not because I'm scared *of* him, but because I'm scared he's going to get an electric shock.

9:09, we're currently calculating this stuff in class. I feel so clever being able to understand that.

as a student studying chemical engineering i was going to complain that it didn't make it into the hierarchy, but then i remembered that chemical engineering is just extreme plumbing. so we did make it into the list, above mechanical engineers. score

6:50 "and it will heeurt" hahaha the hidden puns in your videos are great