[Thurman]

Not sure whether this would be electrical or plumbing so I posted in general.

Got a call to a lady's home with complaint of no hot water. The unit was outside, not covered, and looked like a disasater waiting to happen. I could find nothing wrong with this unit. There was power to both legs of the unit and the ground was tied in correctly.

With the power off and the elements disconnected I had 12.3 Ohms on each element, that should show a good element or so I was taught years ago.

The thermostat tested correctly with the VOhM meter also. Power restored to the elements and all testing shows power to the elements and power going through each element. But still no hot/warm water.

The homeowner tells me that she has talked to a plumber about installing a new unit but the plumber does not wire in water heaters. So I go out to wire in the new unit. First--make sure the tank is full, it is.

Second--check to make sure I have the wiring correct, and I did. Once the unit is wired up and power is on it, everything checks out O.K. The new elements were checked again and all seems well. One strange thing is that I do not hear the noise normally associated with a unit starting up, that sort of "frying" sound from within the tank.

With these newer tanks I'm not sure I will hear this. After thirty minutes or so there is no warm water. This morning she calls to tell me that there is still no warm/hot water from the new unit.

This is not my first water heater wiring but certainly the most puzzling. I'm thinking I'll kill the power to the tank, drain the tank, and inspect the new elements just to be sure. Please--any other ideas? Thanks, David

 

[64pvolvo1800]

Not sure whether this would be electrical or plumbing so I posted in general. Got a call to a lady's home with complaint of no hot water. The unit was outside, not covered, and looked like a disasater waiting to happen. I could find nothing wrong with this unit. There was power to both legs of the unit and the ground was tied in correctly. With the power off and the elements disconnected I had 12.3 Ohms on each element, that should show a good element or so I was taught years ago. The thermostat tested correctly with the VOhM meter also. Power restored to the elements and all testing shows power to the elements and power going through each element. But still no hot/warm water. The homeowner tells me that she has talked to a plumber about installing a new unit but the plumber does not wire in water heaters. So I go out to wire in the new unit. First--make sure the tank is full, it is. Second--check to make sure I have the wiring correct, and I did. Once the unit is wired up and power is on it, everything checks out O.K. The new elements were checked again and all seems well. One strang thing is that I do not hear the noise normally associated with a unit starting up, that sort of "frying" sound from within the tank. With these newer tanks I'm not sure I will hear this. After thirty minutes or so there is no warm water. This morning she calls to tell me that there is still no warm/hot water from the new unit. This is not my first water heater wiring but certainly the most puzzling. I'm thinking I'll kill the power to the tank, drain the tank, and inspect the new elements just to be sure. Please--any other ideas? Thanks, David

. Power to both legs, or power ACROSS the legs? Sounds like you may be seeing 120 but no 240.

 

[joecaption]

Have you tryed opening up the drain to see if hot water comes out?
Does any water come out of the faucets, or does it come out and it's just not hot?
Be sure the power is shut off at the circuit breakers. Disconnect one of the two wires from the heating element. Now using an ohm meter measure the resistance between the two terminals.

If the heating elements are good then you will get a reading of less than 50 ohms. If the heating element is burned out the meter will read infinity, or open circuit.

The meter should also give you an open circuit reading between the terminals and the metal housing of the water heater element.

 

[Thurman]

@ "64pvolvo1800" : Power to each leg is 120vAC as tested against the ground wire. Yes, testing across both legs gives me 220vAC. This is at the connection to the unit, and at the top of the thermostat. Each leg at the element is 120vAC as tested to each screw and the tank, both screws are 220vAC on each element.
@ " joecaption" : Yes I have checked the bottom drain after 30 minutes and it is cold water. Yes water comes out of both faucets at the kitchen sink, hot water side is cold, and cold is cold. Each of the new elements were tested for Ohms with both wires disconnected from the elements. Both elements tested at 12.8 Ohms. Each element was tested by using each screw and testing to the tank for a short--not a short. My next thing to do is to find my darn lost Ohm meter (clamp meter) and test for current draw on the wiring. Thanks for the ideas, David

 

[joecaption]

I suggest your post be moved to plumbing so do not give up yet. Later today when people come home from work someone may come up with an idea.

 

[Biarski]

I suggest your post be moved to plumbing so do not give up yet. Later today when people come home from work someone may come up with an idea.

I'd be surprised if it were plumbing related, since the water is flowing, but I'm no plumber. I would suggest test for voltage at the elements when the thermostat goes from "off" to 130 or whatever you set it at. You should see it go from 0 to 220 and back as the thermostat calls for heat. With a new tank I'm not surprised that everything checks out. Since the problem didn't change from the old to the new, the problem likely exists in the incoming wiring. The most frustrating part is that it's not really all that complicated. Not sure what else to check not being there... please post your findings

 

[64pvolvo1800]

@ "64pvolvo1800" : Power to each leg is 120vAC as tested against the ground wire. Yes, testing across both legs gives me 220vAC. This is at the connection to the unit, and at the top of the thermostat. Each leg at the element is 120vAC as tested to each screw and the tank, both screws are 220vAC on each element.
@ " joecaption" : Yes I have checked the bottom drain after 30 minutes and it is cold water. Yes water comes out of both faucets at the kitchen sink, hot water side is cold, and cold is cold. Each of the new elements were tested for Ohms with both wires disconnected from the elements. Both elements tested at 12.8 Ohms. Each element was tested by using each screw and testing to the tank for a short--not a short. My next thing to do is to find my darn lost Ohm meter (clamp meter) and test for current draw on the wiring. Thanks for the ideas, David

Well in review, watts = heat, watts = volts x amps, amps = 220/12 or about 20,
So 220v * 20a = ~4400w x 2 elements is 8800watts of power that's going somewhere! So yeah, grab your clamp and check it out. If you have voltage on the elements and resistance meeting voltage, then power should be consumed and turned to heat. I suspect a faulty breaker that is passing no current.
Did you have the thermostat calling for heat when you checked voltage on the elements?

 

[Thurman]

"64pvolvo1800"---You're pretty close with your call. The old, and new, elements are 4500 watts each and they are tied to a 30 amp dual breaker to get the 220vAC. It's raining as if Noah is coming soon here now so tomorrow morning will be the amp draw test. One thing I keep going back to is the fact that they have had hot water for over a year with the old unit and then "poof", the hot (or even warm water) suddenly stopped. I think I failed to mention that I pulled the elements from the old unit after it was replaced for inspection and could barely pull the bottom element out due to the calcium/lime build-up on it. That's very common around here though. The top element had some coating but not too bad.

 

[rjniles]

Are you measuring 240 across the element? Or 120 from each element terminal to ground?

 

[paintdrying]

New heater is same as old, you would think there is a weakness in the breaker. It tests with the meter but when the call is made for power the breaker craps out. What does a new breaker cost? Are those dual breakers a known problem. I spent a few years working on very complicated jaguars, many times the performance problems were so simple you could not believe you missed it.

 

[Javiles]

Are you measuring 240 across the element? Or 120 from each element terminal to ground?

i see this all the time from pro plumbers and electricians.. :no:

 

[Biarski]

The breaker might be bad and it could still read 220v, but then it ought to also trip under load... It's probably only about $10 or so depending on the brand.

 

[rjniles]

If you are reading 240 across the heating element, the breaker is not bad.

 

[COLDIRON]

Any hot water from the TP when flipped? Hot water piped correctly and not cut off or valved off somewhere? Did the customer tell you everything ? Like what the people did before you. Thermostat opening to soon or acting up. I'd be real suspicious of that thermostat/limit even though the readings were good.

 

[64pvolvo1800]

Just for kicks and giggles, take the old elements and run 220 to each and plug in briefly. See it they each heat up. That will confirm that the problem is electrical and not plumbing. You have to be losing the 220 TO the element or else they HaVE to heat. Physics

 

[Thurman]

O.K., now the unit has sat for three (3) full days with power on it and when I got there today--NO warm/hot water from the tank. Not at the T&P valve, not at the drain valve, and not at the kitchen sink. Power (220vAC) at the incoming feed to the panel, power after the breaker, power to the thermostat, power to each element but NO warm/hot water. Checked each element once again with Ohm meter---12.8 Ohms, good element. Turned power back on and got amp readings: Top element shows 22 amps on each wire on the element. Bottom element: 22 amps on each wire going to the bottom element. Only thing I know left to do is to remove the elements for inspection, then put the juice to each one for just a very short time to see if they get warm. They should at least get warm shouldn't they "64pvolvo1800"? Physics in play here. There was only one problem with doing this: The person who lives here has no idea where the well is and there is no breaker within the inside panel identified as "WELL". She thinks the well is on her Uncle's land next door. Major decision time here: I have to tell her I have done all I know how to do, she should get her Uncle involved as it is his property, he paid the guys to put the new water heater in and I am done with this one.

 

[64pvolvo1800]

Wait a minute, three days and rated current, that heat is going somewhere. Is there water? Is the pipe on the know hot at least? The elements should've grenaded by now without water, so this must be a flow issue. Very interestissue you got there. No doubt it is not the heater but a plumbing issue after all.

 

[COLDIRON]

Is it tied to an Energy saving device from the POCO? Is there timers anywhere in the system?

Even with no flow there would be heat, the water in the tank would heat up .

Put a amperage readout analyzer on the circuit for 24 hours see what you get.

I know, I know it's really getting complicated.

 

[DidIDoThat]

May sound simple, but have you pushed the " reset " button ?

 

[rjniles]

I hate to keep asking but are you measuring 240 across the top element? If you are and it is not heating, the element is bad.