A simple water heater is more clever than it seems

Pretty clever, ain't it?
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[stevebutters]

Your channel is why I work in hvac now instead of being like homeless or dead or something. Thanks for that!

[chevelleus]

I love how this guy can look around his house, point to literally any random thing like a light switch, toaster or hot water heater and give the most in depth and comprehensive explanation about it.

[ZeroPageX]

I just now learned about sacrificial anode rods! I wish I had known about them when I bought my house. Everyone always told me you just let the tank rust and replace it when it starts leaking (~10 years). First you had me ditch my dishwasher pods, now this! When I started watching your channel, I had no idea you would be saving me money! Great stuff!

[guitarstitch]

I know this is not a DIY or repair channel, but this video actually pointed me in the right direction to diagnose the cause of my short hot water supply. I have a 55 gallon water heater that would run cold just handwashing dishes or during anything but a quick shower. Additionally, I was getting bad smells from my tank. After watching this video, I realized that it was entirely possible I was only running on the top heating element.

Sure enough, I had 240v going to the bottom element with no current draw. Resistance measured in the kiloohms.

Thanks for inadvertently saving me a small fortune in needlessly replacing a water heater. $30 and I'm able to wash dishes while doing laundry, then go take ahower!

[supertoaster]

I built water heaters like this once. This doesn't matter, but the foam is injected with the lid off at just the right amount to expand by the time the lid is assembled on the line. The extra holes in the lid is just a multi-use design for many different tanks, such as tanks with multiple fittings for dual zone or aux floor heating.

[TimeBucks]

I cannot believe how good your videos are..

[TheMateo]

As a mech engineer working in industry, I have to say I love your channel. Sure we have understanding of the mathematical concepts in these vids but things like this I had no idea about. Please don't ever stop making videos like this.

[lcwhr]

Chiming in from France: it's completely common and very widespread here to have heaters only turn on during hours of lower cost power. There's a system that allows the power company, via the power meter, to send a signal to the heater to turn it on or off (and different neighborhoods are turned on at different hours). I guess a reason for all this is that France uses a lot of electrical water heaters, thus it's important to manage their load on the grid.

[javbw]

Late to the comments, I live in Japan with a water heater designed for rate metering and families. It heats the water to 90c during the night and saves it in a giant outdoor tank, distributing the almost boiling water to a reasonable pre-set temp by mixing It with cold water, essentially storing “hot water concentrate” to use to make way more “hot water” than it could ever store - providing enough hot water for 4-5 people for the whole day with some buffer. A control panel lets you ask to make more on demand (guests), and also, separately, manages filling and reheating bathtub water for bathing. It uses 9-12 KW of very cheap power at night, not drawing power the rest of the day in normal operation. This system was installed in ~2006.

[KOrgan]

Beyond the amount of effort you put into your videos for 11 out of 12 months, I want to thank you for including captions in your videos. It really helps me out.

[facurojas]

18:05 I discovered this by accident, we went on holidays for two weeks on summer and we turned off our water heater, when we came back, at the following morning both my parents had a shower and later at night I did, and I've noticed that after five minutes the water was getting unusually cold, turns out we forgot to turn on the heater, and it still had hot water for almost 3 showers, only being FOURTY (40) litters (10, 5 gallons) I was amazed

[EEVblog]

They are called Twin Element hot water tanks here in Australia, and are marketed as such. They don't seem to be that common here. The majority are single bottom element types, probably because of our generally warmer climate. Yes, tank stratification is an interesting topic, it made calcs in my recent whiteboard video on heat pump hot water tanks pretty much just a guess without knowing the actual water flow rates and in/out temps.

[philballphotography]

I just changed my anode a few weeks ago. A plumber let me in on the secret after a water heater needed to be replaced in my house years ago.
Couple of things to note: If your water heater is in a space with a fairly low ceiling you may not be able to get the original factory installed anode out without cutting it in half while you remove it. They are quite long. Easy job for an angle grinder, might be difficult to do with a hacksaw! use some vice grips to hold the bottom half and stop it from falling back into the tank. You can buy flexible ones to replace them for these situations. Every 5 years is a good rule of thumb, but this does depend on your water quality, things like chlorine and mineral content will affect the rate of corrosion. When I swap the anode I write on the side of the tank with a sharpie the date I did it so I can refer back to it. At 5 years mine still had a good bit of life left in it but I swapped it anyway because I was already that far into the job. You might need a hefty 1-1/16" socket to remove the anode and sadly the factory will usually tighten them down super tight, the first time I removed mine I needed to use an impact gun to shift it, you might think a breaker bar would work but water heaters are usually not fixed down well enough, you could end up damaging something.
If you plan to do this you need to turn the water off and drain the tank. You might think you only need to drain a tiny bit out but remember your output is connected to the house, if you're in there with the anode out and someone opens a hot tap upstairs gravity will allow the water in the pipes to drop down and fill the tank. Make sure you drain plenty of water out. You might as well drain enough to remove any sediment which is good practice anyway - some people would say to do that annually.

Even if you have to buy the right socket - anodes cost around $30. Compare that to the cost of new water heaters... with installation, removal of the old one and any damage they do when they leak? could be a 4 digit number pretty easily. Use this math to convince yourself or others that you're actually saving money when you go buy an angle grinder and an impact gun.

fun tip. The drain valve on most modern water heaters has a thread that allows typical garden hoses to connect to it, this can help simplify the draining process so you dont need a lot of buckets.

[SkywalkerAni]

The engineering of water heaters is fascinating- the MythBusters did some experiments with them and found that while they can fail, it takes some real effort to do so.

[crazycgames]

I just installed a heat-pump water heater this past weekend and the change in energy usage is crazy (like 10-12kWh of power a day down to 2.5), and I have it sucking in and blowing out air to the same place. Not great for all areas (I'm in FL, so it helps cool my house down now, too), but wow I'm impressed. Just crazy that i did it and saw your newest video (which apparently I'm 3 weeks late to, lol)!

[TheLivirus]

This channel is so damn awesome, showing the magic behind the conveniences we take for granted.

[christopherzehnder]

This is hands down one of the best channels on YouTube. You restore some of the wonder I felt as a child who liked to take things apart and figure out how they worked. I really appreciate the level of research and thought you put into each video.

[applechoco]

I don't know if anyone's ever said this before, but THANK YOU for making the captions line up exactly with what's being said (in addition to sneaking in a haha funny or two)! I hate having to pause to read frame-long walls of text that aren't even being spoken, and since I use captions for the sake of auditory processing, I can hear all the minor mismatches and just end up irritated. Thank you for doing our eyes and ears a service!

[markeverett]

As a plumber, I have to say this was a great explanation of operation and details of design. If you get the chance, pull an old thermostat and high limit off an electric tank so that you can see how they work. They're very simple but interesting as well.

[TVhyrus]

I inspect failed water heaters for a living. You happen to have one of the most reliable models I've ever seen. I've seen some of those GE (which were made by rheem) go 20 years.