OPERATION & SERVICE
Heating Element Amperage Test
This test should be considered as a first diagnostic procedure for the common service complaints of no hot water or not enough hot water. The heating element amperage test shown on this page is the best procedure to quickly determine which (if any) heating elements are not working properly.
1Secure power to the water heater at the main breaker or disconnect switch.
2Ensure tank temperature is less than 100°F/38°C - dump water to lower tank temperature if necessary.
3Surface Mount Control Models - raise the temperature settings to ensure a call heat is active for all heating elements. Press the red reset button firmly on all thermostat/ECO controls then raise the temperature setting on all thermostat/ECO controls to 140°F or higher - see page 18.
4Restore power to the water heater.
5Electronic Control Models - adjust the temperature settings to ensure a call heat is active for all heating elements. Raise the Operating Set Point in the Temperatures Menu to 140°F or higher. Set all Heating Element Bank Differentials in the Temperatures Menu to 2°F - see pages 52 and 53.
6Using a clamp style AC amp meter: set the amp meter to an AC amperage range just above the expected amperage (100 AC amp range initially). Measure and record the amperage at all heating elements by clamping the jaws of the meter around ONLY one of the wires to each heating element. See the image below. Heating element amp readings should be approximately the same for all heating elements. The normal operating amps for all heating elements is provided in the Heating Element Amperage table on page 22 or it can be calculated using ohms law as explained on page 11.
Service Note: Check all power circuit wiring to the heating element(s) on any element drawing zero or low amps - see the wiring diagram on the water heater. On Electronic Control Models check the contactors on any heating element(s) drawing zero or low amps - see pages 29 - 33. Perform the Heating Element Voltage and Heating Element Resistance & Ground tests (see pages 24 - 26) on any heating elements drawing zero amps or any heating element drawing less than normal operating amps.
If the measured amp draw on any element is considerably less or more than the normal operating amps ensure the voltage and KW rating of those heating elements is the correct value for the water heater being serviced - see Heating Element Ratings and Heating Element Configurations on page 21.
Measuring amperage on an electric heating element. Make sure the jaws of the AC amp meter are clamped around ONLY ONE WIRE to the heating element being tested. Clamping around more than one wire often gives a false zero amp reading.
DO NOT TOUCH THE ENDS OF ANY
HEATING ELMENTS WHILE PERFORMING
THIS TEST
Be extremely careful as there will be high voltage present at the wiring terminals on all heating elements during this test.
Servicing should only be performed by a Qualified Service Agent
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