Bryant 3163 service manual Diagnosing Cooling Problems, Diagnostic Procedures

Diagnosing Cooling Problems

Read this information before attempting to perform service on this refrigerator. Understand the service procedures before performing the service.

WARNING

Always apply the safety precautions on page 1 and the precautions listed below. Failure to follow these safety precautions can result in substantial property damage, severe personal injury, or death.

•Never bend, drop, drill, weld, or hammer the cooling unit. Doing so can cause the cooling unit to rupture, releasing chemicals under high pres- sure. Contact with these chemicals may cause severe burns to the eyes or skin.

•Never attempt to repair or recharge the cooling unit. A defective cooling unit must be replaced.

Diagnostic Procedures

1.Make sure the cooling problem occurs while op- erating the refrigerator in each mode of opera- tion. If not, the cooling problem is not the cooling unit. Refer to Trouble Shooting sections to deter- mine cause for insufficient cooling on identified mode of operation.

2.Make sure the interior venting is not obstructed and is providing air circulation across the cooling unit’s absorber coils and condenser fins.

3.Make sure the 12 VDC ventilation fan is func- tional. The fan will operate whenever the vehi- cle’s interior temperature reaches 85° or higher.

See pictorial and trouble shooting guide on pages 17 & 18.

4.An off-level situation, if the infraction is marginal, will allow the refrigerator to continue to operate at a reduced level of cooling until the refrigerator is leveled. Greater off-level situations will stop the refrigerant circulation and cease cooling. Normal vehicle leveling to provide comfort for the occu- pants is within the refrigerator’s operating limits. The refrigerator’s operating limits are 3 degrees off-level front-to-back and 6 degrees off-level side-to-side. Operating the refrigerator outside of these operating limits for an extended time will cause irreparable damage to the cooling unit.

5.Check the input voltages and gas pressure to insure correct heat input and voltage limits. The specifications are as follows:

a.120 VAC - 108 VAC min. to 132 VAC max.

b.12 VDC - 11.5 VDC min. to 15.4 VDC max.

c.Gas - 10.5" W.C. min. to 11" W.C.

Correct input voltages and propane gas supply are critical for the cooling unit to function properly.

6.Check the area of the cooling unit for refrigerant leaks. The smell of ammonia is a positive sign of a refrigerant leak. When an ammonia smell is detected, the cooling unit must be replaced. An- other sign of a refrigerant leak is the appearance of a yellow powder in the vicinity of the cooling unit. When this powder is observed, the cooling unit must be replaced.

7.Check the absorber coils; the bottom coil will be warm and the top coil will be cooler. If the coils are cold and the cooling units flue enclosure is too hot to touch, there is a blockage in the cooling unit and the cooling unit must be replaced.

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