Service Manual

SERVICE PROCEDURE ACE-IV
High Limit Control Testing
High Limit Control (ECO) Operation
1. Determine if Hi-Limit has actuated. This can be done by simply
depressing the reset buttons. If you hear and/or feel
a small click, the switch has actuated.
2. Use caution and turn power on to water heater and observe
heating cycle following the Hi-Limit Heating Cycle flow chart.
Switch Contacts:
Normally closed.
Open on rise @ 196°F ±4°F
Manual Reset.
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DANGER
High voltage exposure. To avoid
hazard to Life or property, be sure
power is turned OFF to water heater
while performing this procedure.
N
Is water temp
over 196°F
N
Observe heating cycle.
Does switch open?
Switch OK
Is water temp
over 196°F
Replace switch
N
Y
Y
1. STOP, DANGER! Turn power “OFF” to water heater.
2. Water temperature must be below 196°F ±4°F
3. Remove Hi-Limit switch from control panel. It is not necessary
to remove immersion bulb from tank at this time. See
general controls layout on page 4 for location.
4. Disconnect wire leads to Hi-Limit Control.
5. Depress reset buttons to insure switch contacts are closed.
6. Set multi-meter to Ohms setting, Check continuity Thru circuit A & B as shown in the illustrations below.
- Continuity IS present, Switch is okay.
- Continuity NOT present, Replace switch.
High Limit Control Continuity Testing
High Limit Heating Cycle Flow Chart
NOTE
Disconnect
Wire Leads to Control
Circuit “A” Continuity Testing Circuit “B” Continuity Testing
Y
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