The moment he realized the motor had been "fixed" by short circuting was exactly the same as a wizard opening a book of dark magic.

They either succeed or kill themselves trying to prove everyone wrong?

@@inurokuwarz i remember a trick to fix those christmas lights if one bulb is burnt out and you don't wanna try to track it down: hook it up to a taser or other high-voltage source and zap it. this burns and welds the broken filament or something in the broken bulb, so the circuit is closed again. of course, this is very hacky

@@inurokuwarz "And they say dark magic is bad"

@@Spooglecraft and he even discovered it on -accident- Research

It might have been two separate crews doing the work like the plumber who ran the pex around the house and then the HVAC boys installed the heater and valves and stuff and things.

Nice to see you here sir ;)

so they require their services again, if you dont have a special tool youre screwed

To be fair, all the plumbing is a shit show! So messy!

@@TheGazzap45 The wiring certainly is. OK, it's only 24V, but it's still crap.

Same here, it’s cool seeing how someone this smart troubleshoots something I’m very familiar with

HVAC, more like highway robbery!

Most likely not, far more likely dust causing a short circuit which at LV remained, but HV burnt it away.

@@mrtango1824 Dust isnt conductive enough to cause a short circuit at low voltage.

Arc welding!

@@Godspamit Could have also been a loose or oxidized connection that was open cicuit at 30V,but became shorted at 120V and the connection welded from the high current.

I'm guessing metal shavings from the constant operation

Or it could be one of the safety features when you ask for a low flow rate (valves almost closed). I think these type of units need at least some flow, else they could get dangerous

Yes, but it should be a restricted flow.

you have been promoted above Doctors.

So it's a flyback diode.

We have this bypass in chiller water cooled systems. It exists so the evaporator has a constant water flow even if there is no demand in the line.

@dejuren Yes. But it might hurt.

​@@dejuren1367you'd be shocked

That sounds like such a cool career/educational path. How old are you, if I may ask?

@@kerimgueney Since you haven't gotten a reply, here's the way I got into HVAC which is one of many possible paths. I was an electrical apprentice for a while, then got a job with an HVAC controls company installing control equipment. I've known plumbers that got into HVAC the same way. From there, experience and interest can move you into the refrigeration side or the controls side. I went the controls route, but it would have been just as easy to go in any direction, and most trades companies will cooperate with schools to complete your training at the same time. Basically start at the bottom and work your way up, following your interests.

@@zierlyn thank you. I appreciate the detailed response.

They haven't found a way yet considering how many dudes turn into mist on a yearly basis wrangling the damn stuff.

Hehe, _potential_ ly.

Wait till you realize that the majority of rocket science is just fancy plumbing.

Yeah. The fact that hot water and cold water pipes are just shorted seems like wizardry and rocket science.

@@SneeuwPoesjes get 2 liquids to the bottom of a tube uh huh, "Fancy" plumbing

Two words: Colin Furze

I have some electrical engineering degrees and don't know jack about plumbing. I just call the plumbing guys and pay them, and all is well.

I read that comment just as he gets to the explosion scene lol

Honeywell & M.K. electrical goods have become fairly unreliable over the last few yrs, but the M.K. prices have remained rather high. ( M.K. & Honeywell are the same same company)

Planned obsolescence.

Sure thing buddy I could say the same about caleffi, it does have a higher flow rate, but the inverse flow of ac to dc conversion with lower string coils per cubic metre has led to a lot of companies opting for honeywell systems. Not to mention the 8 year old who got electrocuted at 45 meters distance from a caleffi motor last spring which caused a black out in arkansas?

@@callmex5406 can you provide me with the data on this incident.

@@garyangelstad5212 obviously the news was taken off the internet after the company issued a media blackout. The courts were in on it.

That's why I liked this one more than others

That's weird, most of us like when he blows stuff.

Yeah, these are nice videos along when he builds (and blows up) something

Me too!

He fixes stuff?

Mehdi : What are you burning ?!?! The wire : idk man .

The only time I've taken one apart instead of just replacing the head was when I was a trainee and was instructed to "change the head on that valve". Still remember my bosses confusion 15 years later as to why was the old one in pieces in the box when at first he thought I was wasting time on pissing about. Difference between theoretical knowledge and practical knowledge.

Makes me wonder if they're using an older transformer made for 110 v hence why the higher output on 120 v... or maybe the plumbers that did this are dumb and got the wrong transformer?

@@bluerilius4362 Could also be a chinese transformer because they mostly rate stuff for 110 or 220 V, not for 115, 120, 230 or 240.

@@mernok2001 perhaps that may be

Lightbulbs are not that easy any longer.

I had the pleasure of being taught physics by a FermiLab scientist. She was smart enough, and I mean no disrespect she was very smart, to know when I needed conceptual vs practical answers to questions I had about capacitors, inductors, etc. Different people need different approaches to electrical engineering.

mechanical stuff we can actually see things in motion. 1 action cause another. electricity and electronic is like wizardry to me.

@@muzallisam5068 oscilloscopes are the prized possessions of electrical engineers. They make the invisible world of electricity visible.

Hey I work with an electrical engineer and he doesnt even have a simple understanding of how uneven pressing forces would create uneven pressures

As long as a child can fit inside we can keep the trai... boiler running forever

Basically the exact opposite of smartphone design!

That is why things with "industrial" grade tend to be big for seemingly no reason

@@QualityDoggo yet most people want them thinner and more complex lol.

Larger heat exchangers are generally more efficient as well.

Unless it's in winter and you have no heater left.

@@goku445 honestly that comment was like, at least 75% sarcasm. I'm not actually a fan of having to do this sort of thing :P

@@jonasdatlas4668 Right. I read too fast your comment. I actually enjoy fixing stuff, that's why my comment.

untill we let the magic smoke come out, then we have none :P

I have been installing complexed hydronic systems for 40 years. I would never let an electrician much less an electrical engineer wire any of my systems. lol

As a Mechanical Engineer, I'm tempted to ask "a friend" that I know to turn Medhi into a frog! ;) LOL! Of course I wouldn't really do that, but if my friend _did_ turn him into a frog, then he could redo some of Galvani's experiments with electricity & frogs. Seriously though, his troubleshooting was interesting and the repairs appear to have worked, at least until the too-high voltage kills more motors. I half expected him to replace the power supply with a regulated 24VAC PSU.

@@anthonyspadafora1384 What, because we'd be able to point out all the things you've been doing wrong for those last 40 years? :P ;) Sorry couldn't help myself

Hi

Mehdi*

@@eduardopereira1915 that was the joke yes.

@@Vesterian Ok.

But what was burning actually?

kzfaq.info6lrPUb5echQ

Michael Steeves, same here. And I'm certain Mehdi's heirarchy opinion is completely unbiased. 😅

As an astrophysicist I do not.

As mechanical engineer student i feel insulted. i did take extra electrical classes tho.

@@benjamin4321 and structural engineers are below janitors lmao

As an IT engineer I felt like I ducked in time.

You should, with your moniker, look at Big Clive's video on wood-burning art using high-voltage transformers. It would, er, relax you...

Lol i remember when I used to be like that

My thoughts exactly, I felt right at home. ;)

Same as "yellow chemistry bad" I'd imagine.

Every time I've hired a plumber they'll see something the last plumber did and go "Yeah that's garbage, did you get an idiot to fix it?"

@@inurokuwarz exactly

@@inurokuwarz Sounds like programmers too

@@inurokuwarz You wouldn't get it, its a plumber thing. Just believe us, we mean it.

@@inurokuwarz And then you tell him, that it was he who was called last time 🤣

Perhaps it has something to do with machines?

Mechanical and electrical 😊

@@jrisner6535 drain lines and furnace venting makes them plumbers too

Cryptographer you are, huh? 😉 Vulcan engineers? German? Japanese? Don't give me any Static, I am trying my best. How about any engineer that knows when to use a normally open circuit over closed, and vise versa?

They aren't engineers, they are architects!!!!

I'd love to know what was burning haha

@@Agent24Electronics agreed!!

kzfaq.infoH3hL08Ka-_4?feature=share

kzfaq.infoH3hL08Ka-_4?feature=share

Nice

Microcontrollers are the best thing since sliced bread.

@The Game Shorts 🅥 you've posted this link on every video I've seen last week. It's an ice cream recipe... You're spamming comment sections for an ice cream recipe..

Hahahaha made my day (mechanical engineer)

6:00

Reminds me of that one time he pulled the auto transformer and says it “””REDUCES””” the voltage

You can also probably get the motors rated for mains voltage and use the 28V to control a relay. Or just unwind a few turns from the transformer (or wind a few turns backward) so the voltage at full load is lower than 24V (use an autotransformer to find out the minimal voltage at which the valves still work and just use slightly higher voltage.

My radiators just have a mechanical thermostat on each one.

I worked on an old 5 zone system that had 5 circulating pumps. Expensive, but it has super redundancy. One of the zones had a high velocity pump. Then someone replaced it with a standard circulating pump. The zone for the bedrooms (which were at the far end of a sprawling house) was not keeping that end of the house warm in really cold weather.

yeah, and then when they move the new owners need an electrical engineer to fix everything that he over engineered because your average plumber/hvac guy isn't going to want to touch it.

That was honnestly disappointing when he said : "Done!" And we saw nothing. wtf

Cool

But I bet yours works.

This heating system is barely the minimum requirement in Europe!

@@MyNotSoHumbleOpinion Yeah, not at all

I have a kerosene furnace....

@@g3th_ then let's say in civilized Europe. in Italy every replacement of the heating system must be done in this way with at least a condensing or biomass boiler! Each new construction must instead have at least one hybrid system with a water heat pump, solar panels and photovoltaic panels!

I was just about to write the same :)

Correct. They also need to keep it simple with as few parts as possible as must be reliable for hundreds of operations.

Thats exactly why such design is used, im stunned this EE guy can't realize such simple concept...

Why does a valve needs to be closed during power outage? The water supply/circulation has stopped as the circulation pump has stopped too.

Why would the valves need to close by themselves during a power outage?

But the circulation pump would shut down in a power outage, who cares if the valve is open in a closed loop system? A simple check valve will stop any water reversing flow. These days (alleged chip shortage aside) micro-controllers are dirt cheap, most commercially available (heck, even hobbyist versions) have enough IO pins that can be multiplexed to work very cheaply. The coding cost is debatable as well, and entirely dependent on the number of units sold/installed. Here in Australia such water based heating systems are rare, so yeah, all components inc programming would be expensive, but I believe pretty common in the northern hemisphere so less of an issue. And your assumption of a decent power supply being more expensive than the potential "life of product" power drain of this cheap alternative could be argued. "mostly doesn't fail before the warranty expires" is cold comfort (pun intended) and a poor metric... good for the seller/manufacturer I guess, but this planned obsolescence is bad for the planet, as it needs yet more replacement parts to be made and consumed over the actual life of the entire installation.

so add bit of code or even circuit logic that upon restart, drive all valves to close/open for few second and then normally control them.

imo you really don't need much I/O Pins, just rs-flip-flops, a shift register and a timer. Heck, you could even use an fpga for all that. Implement a proprietary or public open source serial protocol and all you'd need are like two I/O pins at minimum, better yet four as twisted pairs for RX and TX.

Why not relays?

It wouldn't even need any electronics, just a single "horseshoe" rocker double pole switch would work

I like that doctors stayed on the same teir XD

i mean, also electrical engineering is basically plumbing for electrons XD

Was hopping down to look for exactly this comment, simpler mechanical design by leaving the motors live and if the system ever failed electrically the valves should close. Makes me wonder if there is an elegant way to reduce/eliminate the power use without losing the failsafe.

@@Loran425 Oh, there is a way: pneumatic actuators with spring return to closed. The obvious problem is the need for compressed air to operate the actuators.

@@Loran425 a small latch on the spring actuated by a small electrical current? Basically, add something that can be controlled with the smallest possible electrical circuit to reduce the power needed. Or, some failsafe that is sensitive to a state change in the electrical system. I don't know enough to imagine what that would be, probably some digital doohickey.

@@Loran425 internally piloted solenoid valve have much less power consumption and have exactly same behaviour as this.

@@Loran425 My old dishwasher door actuator uses a wax motor so you get it hot and it opens by thermal expansion. Without power the wax cools and contracts. It's not critical these valves open lightning fast so why not. All they are is a heater, wax that expands under heat, and a spring. On the plus side the valves would close suuuuper slow so as to never slam shut.

kzfaq.infoUgkxDSHMD50O3HOqk5imXehDZN3caF4WiqtT

kzfaq.infoH3hL08Ka-_4?feature=share

You can feel the sketchyness ooze through the screen

I didn't see any earthing either

that's why you don't let plumbers do electric work

No problem, it's ony Americam wimpy 110 volts, try getting away wiyj that on 240volts!

Seems like a no brainer

@Don't Read My Profile Photo i wont lol.

Normally there will be a thermostat in the boiler to regulate the output temperature. Pretty sure that loop is there to enable continuous flow even if all the heating circuit valves are closed.

It also make the return water a bit warmer when goes into the hot boiler parts and reduce temperature shock.

Lol what

It is a bypass, but not for the reason you mentioned. The closely spaced tees provide what we call ‘hydraulic separation’. By doing this, the water flow through the boiler remains constant, regardless of how many zones are turned on.

I doubt that its used to lower the temperature since its a gas boiler that can just turn on/off or modulate when necessary. Such a precaution is only required if you have a wood furnace or have a heater that heats up a seperate tank with the water inside. This would be one of the reasons why you would require a bypass here

The supervent closest to the bypass actually just removes air from the system, the pressure relief right next to it dumps water into a drain.

Why would it connect to the inlet? I think it should vent to atmosphere / drain instead. The pressure in the system can still rise otherwise.

@@marco23p it doesn’t. The big thing with Honeywell on the side just vents air that gets trapped in the system the pressure relief to the right of that just dumps water down the drain, which isn’t great as you’ll never know when it’s hitting pressure

if medhi was an aerospace engineer he would know that!! (taught in thermo 1)

Neither valve position is "safer" than that other tbh. It's is a legacy system that was designed for least possible complexity; voltage applied valve opens, voltage not applied valve shut. These would traditionally have been controlled by a simple bi-metallic strip style thermostat.

@@underdweller If the thermostat fails why would the boiler continue to run?

@@underdweller The heater needs electricity to turn on. If the motors don't have power the heater won't have it either.

@@danieljensen2626 The motors can lose power independent of the heater, or fail themselves just like what happened here.

Close but it's precisely because there is no power when the thermostat is *not* calling for service.

Speak for yourself 😂

It is. The most versatile of engineers

if you can pee you can plumb. mechanical engineers need to be above people that can pee

In electrical speak, they want the water lines supervised. Aka if there's a problem, they want someone to notice and fix it. In this case, the system is telling you there's a problem with the valve by cutting off your heat till you fix it. Fire alarm systems work in a similar manner, except they get nice and loud speakers and flashing lights to tell you something is wrong and you need to GTFO (or just the control panel starts to scream to get a tech in to fix it)

Plumbing except the leak will melt your eyeballs

Plumbing is just the base of it all apparently. Aren’t electrical engineers and electricians just electron plumbers?

So is it a really short single pipe heat exchanger?

@@im1random263 www.caleffi.com/sites/default/files/coll_attach_file/idronics_15_na.pdf This is a really well done article on this. Enjoy

@@im1random263 p.27

@@anthonyspadafora1384 🤔