Double Element, Non-Simultaneous, Single Phase
Operation (continued).
Not Enough Hot Water (continued).
7. Check voltage acrossterminal L4 of upper
thermostat and terminal1 of lower thermostat
(see illustration11).
A) Rated voltage NOT present,
- check wire connection between thermostats.
B) Rated voltage IS present, okay, go to step 8.
8. Adjust lower thermostat to highest setting. Water temperature in
tank must be belowthe lower thermostat setting for this test.
9. Check voltage acrossterminal L4 of upper
thermostat and terminal2 of lower thermostat (see illustration 12).
A) Rated voltage NOT present, replace lower thermostat.
B) Rated voltage IS present, thermostat is ok.
WARNING
High voltage exposure. Use caution to avoid
personal injury during this procedure.
Illustration 11
Illustration 12
WARNING
Be sure thermostats are reset to their original
temperature settings as found prior to
thermostat testing
Page 18
SERVICE PROCEDURE RE-III
Residential Thermostat Testing
Water Temperature In Tank Is Above Thermostat Setting.
1. This procedureassumes Line voltage, ECO and elements are in working
order.
2. Adjust upper and lower thermostatsto the lowest setting.
3. Turn power “ON” to water heater and set multi-meter to “Volts AC”.
4. Check acrossterminals L4 and T2 of upper thermostat
(see illustration 8 on page 17).
A) Rated voltageIS present, replace upper thermostat.
B) Rated voltageNOT present, upper thermostat is okay. Go to step
5 below.
C) Lower than rated voltage IS present,recheck for grounded upper
element (see page 15).
5. Check acrossterminals L4 and 2 of lower thermostat (see illustration 12).
A) Rated voltageIS present, replace lower thermostat.
B) Rated voltageNOT present, lower thermostat is okay.
C) Lower than rated voltage IS present,recheck for grounded lower
element (see page 15).
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