[Solidify]

Yesterday my tenant rang saying she had no hot water. I went to her water heather (each tenant has one) and reset the red button where the screw terminals are exposed. I heard a click and then I heard water start flowing again inside the tank and half an hour later, the water was discharging hot water again. I tested the resistance of both elements with my DVM and they both checked out at 20.4 ohms (3000W tank at 240v), which is fine according to what I referenced. So both elements are OK.

However, I should mention that when I first arrived at the tank before resetting the button, I saw signs of water leakage all over the garage floor and severe oxidization and condensation inside the connection terminals. These tanks (all four of them) are stored in my garage, right beside the garage door.

I checked under the tank but I can't spot leaking. Either it's just condensation leaking or it's leaking very very slowly over time from somewhere. I also can't spot the date on the tank to see how old it is (nor can I remember).

The tank works now though. I'm just wondering what's the problem. Did the condensation make it trip the breaker that I had to reset?

 

[Solidify]

.....

 

[TimPa]

its possible that the wet floor was a result of water coming from the safety valve,located on the side near the top. they open up when too much pressure in the tank is a result from the unit overheating the water. maybe the contactor stuck closed??

or, its a leaky tank...

 

[Solidify]

its possible that the wet floor was a result of water coming from the safety valve,located on the side near the top. they open up when too much pressure in the tank is a result from the unit overheating the water. maybe the contactor stuck closed??

or, its a leaky tank...

The shape of the water stain on the ground is too perfectly around the circumference of the tank for it to have come from the safety valve. My garage is also pitched towards the right of the tank where there is a sewer so if that were the case, no only would the water marks be more towards the right of the tunk, under the safety valve, but they wouldnt have spread towards the left of the tank.

The wet mark really seems to point to the tank leaving from under since the water mark is perfectly around the tank.

How do I troubleshoot this if I can't spot the leak and the water is hot now and everythinf works?

 

[Jump-start]

Thermostat is stuck. Being that the water heater looks like its leaking uncontrollably it needs to be replaced.

 

[mpoulton]

The red button is a thermal limit switch. If the surface of the tank gets too hot, that device trips and shuts off the power. It should never trip unless something is wrong. I would guess that the water damage to the thermostats caused one of them to stick on, and the heater continued to heat until the safety switch tripped.

There is definitely something wrong with this heater. The water appears to have been flowing down the inside of the shell from the top. You can see rust streaks near the top of the upper thermostat, so the water must be coming from above that area. Check the connections on the top of the heater and see if you can find evidence of the leak up there.

Regardless of where the water came from, it would be a good idea to replace the thermostats. They've obviously been wet and are probably corroded. That's likely the reason the unit overheated and it will probably continue to malfunction in the future. You also mentioned that you could hear water "flowing" in the tank after you reset the safety cutoff. Most likely that was the sound of the water boiling around the heating element. That can be normal, but is often a sign of excessive mineral deposits on the elements which shorten their life. Consider descaling the unit or pulling the elements for inspection/replacement while you're changing the thermostats.

 

[Solidify]

The red button is a thermal limit switch. If the surface of the tank gets too hot, that device trips and shuts off the power. It should never trip unless something is wrong. I would guess that the water damage to the thermostats caused one of them to stick on, and the heater continued to heat until the safety switch tripped.

There is definitely something wrong with this heater. The water appears to have been flowing down the inside of the shell from the top. You can see rust streaks near the top of the upper thermostat, so the water must be coming from above that area. Check the connections on the top of the heater and see if you can find evidence of the leak up there.

Regardless of where the water came from, it would be a good idea to replace the thermostats. They've obviously been wet and are probably corroded. That's likely the reason the unit overheated and it will probably continue to malfunction in the future. You also mentioned that you could hear water "flowing" in the tank after you reset the safety cutoff. Most likely that was the sound of the water boiling around the heating element. That can be normal, but is often a sign of excessive mineral deposits on the elements which shorten their life. Consider descaling the unit or pulling the elements for inspection/replacement while you're changing the thermostats.

There are no signs or leaking or corossion at the top of the tank. I dont want to replace the thermostats if theres still a leaking issue and it was ruin them again ($$$). Also, the tank is between 8-10yrs old. How can I determine where the leak is coning from and if it warrants replacing the tank in its entirety, considering I dont see any corossion or leaking at the top?

 

[Oso954]

It is definately leaking. You got 8-10 years out of it. I would not mess with it, I would just replace it.

3000w 40 gallon heaters w/6 yr warranty are pretty much bottom line. From what I see, Moffat brand seems to be sold primarily by Canadian Tire. The comments there on older units and warranty are not very favorable.

It might be a good time to do a visual inspection on the other 3 units there.

Also, when was the last time you drained them and any other water heaters in your complex ?

 

[TheEplumber]

Looking at the water stains in your image- I suspect a union or nipple at the top of the tank is leaking. This is flowing of the top and down to the thermo and element.

 

[Solidify]

I know I should take up that pratice but I never drain them. I`ll start doing that regularly from this point on.

3000w 40 gallon heaters w/6 yr warranty are pretty much bottom line.

OK, so I`ll replace the water heater. Which would you recommend in that case?

Edit:

Looking at the water stains in your image- I suspect a union or nipple at the top of the tank is leaking. This is flowing of the top and down to the thermo and element.

I inspected it from the top and I don't see a visual issue. I'll just replace it. I'll replace the disconnect box for this water heater at the same time, since it's still running on fuses (I'll take this opportunity to upgrade it to a breaker box).

 

[Oso954]

I would compare the features on the units that are available in your area.
A 4500 watt unit is going to give you a faster recovery time than a 3000w unit.

Insulation is another factor. Your old unit is probably an r8. I would be looking for R16 minimum and consider R24 depending on how cold that garage gets.
An alternative would be adding water heater blankets.

In some cases, the differance between a 6yr warranty unit and a 12 year warranty unit is only the length of the anode rod. If you are checking anode rods periodically, and replacing them when needed, the price differential isn't worth it. But if you are trying to minimize the maintenance time, I would buy the longer warranty unit.

Speaking of the anode rods, I would pull the rod on the unit you are replacing during or after replacement. You will learn how to do it. It will also give you an idea of how corrosive your water is. Changing the anode rods on the other units of similar age (or even a few years younger) would most likely lengthen their service life. In some cases it will double it.

I would talk with the plumbing supply companies in your area to see what they recommend. I like units where I can pick up parts locally. I think paying more than a big box price is worth having parts and/or service. Who knows, if you tell them you have a multi unit complex, they might give you a break as compared to a single family homeowner.

 

[Solidify]

If you are checking anode rods periodically, and replacing them when needed, the price differential isn't worth it.

Ive never done that hihi

Yep, Ill def take that old one apart to get a better idea of how it works. I don`t know how to solder so I think ill have to call a plumber to make the new connections, since my piping is all copper. Even if I wanted to do pex, id have to rent the tool and then solder the adapter

 

[Solidify]

Scratch that, I just realized I can buy a pex to copper adapter with a compression fitting snd save on calling a plumber.

 

[Solidify]

Is this what I would be replacing my old fused disconnect with?:

http://www.renodepot.com/en/safety-switch-1334054

 

[taylorjames]

Leakage is not a good sign for the water heater as it can hurt the heater efficiency. That's why it is mandatory to get it fixed using the help of experienced professionals.

 

[Solidify]

Leakage is not a good sign for the water heater as it can hurt the heater efficiency. That's why it is mandatory to get it fixed using the help of experienced professionals.

Mandatory using the help of experienced professionals as per which regulation? I know I can't do my own electrical work in Quebec but I wasn't aware that it was mandatory to call a plumber to replace my water heater...

 

[beenthere]

Leakage is not a good sign for the water heater as it can hurt the heater efficiency. That's why it is mandatory to get it fixed using the help of experienced professionals.

Perhaps in your country its mandatory. But not in most countries.

 

[Solidify]

Why do some water heaters have elements with different wattages? How do I know which wattage my elements should use?

 

[Oso954]

The current water heater (3000w) has a recovery rate about 16 gallons an hour.
A 4500w will have a recovery rate of about 22 gallons an hour.
Quicker recovery means fewer complaints relating to no hot water.

As long as you have a 30amp circuit for each heater, I would use the 4500w.

 

[Solidify]

So if the circuit breaker that controls the water heater is 30A, I can use 4500W heating elements if I'd like to?

And if so, if I buy a water heater that comes factory installed with a 3000W upper and lower heating element, and the maximum rating is 4500W, may as I eventually replace both elements with 4500W elements (assuming the circuit breaker is atleast 30A)?