18
Double Element, Non-Simultaneous, Single Phase
Operation (continued).
Not Enough Hot Water (continued).
7. Check voltage across terminal L4 of upper
thermostat and terminal 1 of lower thermostat
(see Figure 11).
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 below the lower thermostat setting for this test.
9. Check voltage across terminal L4 of upper
thermostat and terminal 2 of lower thermostat (see Figure 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.
Figure 11
Figure 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 procedure assumes Line voltage, ECO and elements are in working
order.
2. Adjust upper and lower thermostats to the lowest setting.
3. Turn power “ON” to water heater and set multi-meter to “Volts AC.”
4. Check across terminals L4 and T2 of upper thermostat
(see Figure 8 on page 17).
A) Rated voltage IS present, replace upper thermostat.
B) Rated voltage NOT 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 across terminals L4 and 2 of lower thermostat (see Figure 12).
A) Rated voltage IS present, replace lower thermostat.
B) Rated voltage NOT present, lower thermostat is okay.
C) Lower than rated voltage IS present, recheck for grounded lower
element (see page 15).
