Dometic
®
MANUAL
Refrigerators
33
5C. GAS THERMOSTAT
(RM2804 & RM2604 ONLY)
On the LP gas mode, full line pressure is directed
through the thermostat to the burner until the thermostat
senses that the refrigerator cabinet has reached proper
cooling temperature. At that time an internal valve closes
and redirects the gas flow through the by-pass screw.
This reduces the amount of LP gas going to the burner
assembly. The gas flow remains in this “by-pass” mode
until the thermostat senses that the refrigerator cabinet
needs more cooling. Again, the thermostat directs LP
gas flow through the thermostat at full line pressure until
the cabinet temperature is sufficient. The thermostat is
calibrated by the manufacturer so that at mid-range the
cabinet temperature should be approximately 40 de-
grees Fahrenheit. To check the calibration of the
thermostat, place a container of water in the cabinet of
the refrigerator and operate at mid-range setting until the
thermostat is satisfied. Then, check the temperature of
the water. It should be approximately 40 degrees. We do
not recommend any calibration in the field. If calibration
is not correct, replace the thermostat. To check the
thermostat for proper gas flow, set the thermostat to
maximum and check the gas pressure at the pressure
test port. It should be line pressure, between 11 to 12
inches water column. If you have less than 11 inches of
water column pressure, the next step would be to shut
off the gas supply and remove the by-pass screw. Then
install a by-pass screw that does not have the small o-
ring on it. Next, turn on the gas supply and take a
reading. If the manometer now reads 11 inches of water
column, the thermostat is defective and must be re-
placed. If the by-pass screw test shows no change in
pressure, the problem lies in the filter, the shut-off valve
or the gas supply. Shut off the gas supply, remove the
by-pass screw, replace it with a proper one that has an
o-ring and turn the gas on.
NOTE: Check for leaks with an approved LP gas leak
solution whenever any part of the gas system has been
worked on.
6C. DUAL THERMOSTAT
LP GAS MODE
On the LP gas mode, full line pressure is directed
through the thermostat to the burner until the thermostat
senses that the refrigerator cabinet has reached proper
cooling temperature. At that time an internal valve closes
and redirects the gas flow through the bypass screw.
This reduces the amount of LP gas going to the burner
assembly. The gas flow remains in this “bypass” mode
until the thermostat senses that the refrigerator
7C. FLAME INDICATOR METER
(On Top Mounted Controls Only)
The flame indicator meter is basically a DC volt meter. It
reads DC millivolts coming from the thermocouple. If the
millivolts from the thermocouple are 5 millivolts or more,
the red needle in the meter should be in the green
section.
If the blue wire to the meter is shorted to ground or if the
blue and red wires are shorted together, a flame failure
condition could result.
8C. FILTER
A filter is located in the inlet fitting to the thermostat. It
protects the internal valve portion of the thermostat by
collecting any particles and/or oil that could get into the
LP gas line. The filter can become saturated and cause
a restriction to gas flow. This could cause a lack of
cooling on gas mode. If you suspect a restriction, first
verify the thermostat and bypass screw are good. If
these components are good, and filter is restricted,
replace thermostat.
9C. ELECTRIC THERMOSTAT
(For RM2804 & RM2806 Only)
It is an electric only thermostat. On 2-way models it
controls the AC heating element. On 3-way models it
controls the DC heating element as well as the AC
heating element. The thermostat regulates the cabinet
temperature by making and breaking the heat source
circuit. The internal mechanism breaks contact (continu-
ity) when adequate cabinet temperature has been
reached. Check the thermostat for continuity or use a
jumper wire with insulated clips and bypass the thermo-
stat.
NOTE: Care should be used. Do not short to thermostat
casing. Also remove the jumper after testing is com-
pleted.
If the above test allows the refrigerator to operate,
replace the thermostat.
To Next Page
Loading...
Need help?
General
