Resistance; Testing The Cooling Unit In Bypass Mode; Replacing The Cooling Unit - Dometic DM2652 Service Manual

Americana and New Generation Refrigerators
4. Disconnect the LP gas supply line from the gas valve
and cap the gas line.
5. Remove the nut and screws securing the gas valve to
the burner housing.
6. Slide the gas valve out from the burner housing.
7. Remove the screws securing the burner housing to
the back of the refrigerator and remove the burner
housing.
8. Perform these steps in reverse with a new burner
housing to complete the replacement.
9. Verify there are no LP gas leaks. Refer to "Performing a
Gas Leak Test" on page 30 for more details.
8.4 Testing the Climate Control
Heater for Resistance
1. Disconnect the unit from all power sources (120 VAC
and 12 VDC).
2. Depending on the model of the refrigerator, flip up
the lower control module cover (New Generation
and some DMR702 models) or locate and remove the
screw securing the cover to the refrigerator wall.
3. Refer to the "Wiring Diagrams" on page 15 to
locate the wiring to the climate control heater.
4. Set the multi-meter to the Ohms resistance setting.
5. Attach the leads of the multi-meter to the terminal
ends of the wires to the climate control heater.
The reading should be between 22–26 Ohms. If the
reading is out of specification, it indicates a faulty wire
to the climate control heater.
I Consult the operating manual for the multi-meter
for specific device function.
EN
8.5 Testing the Cooling Unit in
Bypass Mode
The temperature outside the refrigerator must be
I
warmer than 50°F (10°C).
1. Prepare the thermistor for the test determined by the
model of the refrigerator.
– New Americana, perform the steps in "Replacing
the Thermistor" on page 45 to remove the
thermistor.
– New Generation, perform the steps in "Replacing
the Thermistor" on page 45 to install a spare
thermistor and position the thermistor to hang out
of the lower access door.
2. Set the refrigerator to electric.
3. Place a bottle of water in the fresh food compartment.
4. Let the refrigerator run in this state for 6-8 hours.
5. Use a substance thermometer to test the temperature
of the water in the bottle.
The temperature in the fresh food compartment
should read within ANSI specifications (43 °F (6 °C)
or lower). If the reading is out of specification, it
indicates a blocked cooling unit.

8.6 Replacing the Cooling Unit

1. Perform the steps in "Removing the Refrigerator from
an Enclosure" on page 30.
2. Remove the handles (if needed) and lay the
refrigerator face down on a protected surface.
3. Remove the screws securing the outside frame of the
cooling unit to the box of the refrigerator.
4. Remove the electric heating element(s) from their
pockets in the cooling unit and set aside to re-use.
5. Pull the flue baffle from the top of the burner tube of
the defective cooling unit and set aside to re-use.
I Replacement cooling units do not come with a
replacement flue baffle. The flue baffle must be
transferred from the defective cooling unit to the
new cooling unit.
Service Procedures
31