SERVICE PROCEDURE RE-ILine Voltage & High Limit (ECO)Testing
WARNING
High voltage exposure. Use caution whenmaking voltage checks to avoid personal injury.
Line Voltage Testing
Illustration 2 Illustration 3
1. Turn “OFF” power to water heater.
2. Remove access cover(s) from front ofwater
heater. Remove insulation and plastic cover
from thermostat.
3. Setmulti-meter to volts AC.
4. Turn power “ON” to water heater.
5. Check voltage across terminals L1 & L3
of upper thermostat (see illustration 2).
A) Rated voltage IS present, power to the water
heater is okay.
B) Rated voltage NOT present, Check circuit breaker
at service panel.
ECO reset
button
1. Check voltage across terminals L1 & L4 upper thermostat (see illustration 3).
A) Rated Voltage IS present, ECO is okay.
B) R ated voltage NOT present, proceed to step 2.
2. Turn power “OFF” to water heater and firmly press ECO reset button on thermostat. Turn power “ON” and recheck
voltage across terminals L1 & L4 of upper thermostat
(see illustration 3).
A) Rated voltage IS present, the ECO has previously opened indicating the water in the tank, at
some point did overheat, check the following:
1. Thermostat must be in full contact with tank.
2. Be sure heating elements are not shorted to gr ound (see page 9).
3. Proper thermostat operation (see procedures beginning on page 10).
B) Rated voltage NOT present, water in tank may be over heated.
1. If water is hot, turn “OFF” power to water heater and flow water through tank to cool below set point
of upper thermostat. Recheck voltage per s tep 1.
2. If water is cool, Replace upper thermostat.
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High Limit (ECO) Testing
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