h/w heater probs

nking

40g hot water heater no hot water:
we went on a servce call yesterday for, no hot water. i sent one of my guys. he replaced the lower element and left. i got a call back today for no hot water again. i went over myself and checked the unit. i tested the voltage from the breaker i had 240V, then i checked the voltage going through both elements, the top 240V the bottom 000V. i then shut the breaker off and tesed continuity in both elements i had 13-14 on my tester for both elements. i also grounded my tester and checked both sides of both elements and they all read 120V. i still have no hot water and just to boot i changed out both thermostats. any suggestions or advice would be appericated, thanks

frenchelectrican

Did you check the connection at the top of water heater ?? from time to time I will find a loose connection there due your DVM meter can read the voltage but not engough load to shunt it out.

Few case the upper limit switch can be tripped or have bad connections.

13 ohms is about right for 4500 watt element and with cold tank the upper thermost will turn on the upper element and leave the lower one off until the upper one get warm then switch over to lower element.

However one warning if you have TOU { time of use or off peak system } it will get tricky to deal with it.

and I know you mention service call and is one of your guys is qualifed electrician ?? this part is pretty strict on code and safety.

Merci.
Marc

AllanJ

Normally only one element comes on a time.

A small number of heavy duty heaters (with heavy duty wiring and usually time of use meter/switching) may put power on both elements.

With time of use switching there will be no power at the junction box where power comes in (top of the heater) during peak hours.

If you got 240 volts at the top element and 000 volts at the lower element then the heater should have been working.

Heaven forbid, per chance was the power turned on before water was gushing from a hot water faucet upstairs, that is, before proving that the tank was full first? Running any water heater when it is not full will cause damage, possibly in less than a minute, and in the case of a burned out element you can still measure 240 volts across it with the power on.

__________________
The disadvantages of crab apple trees. In summer, the apples are too sour to pick and eat. In winter the birds come and leave dropping all over the place.

nking

i figuered it out guys, i had a bad thermostat right out of the box. so yesteryday when i changed the lower one the new one was no good. good note some new parts are defective, thanks to those who commented!