Trane RAUC-C20, Installation Operation & Maintenance

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SS-SVX09A-EN 107
Service & Maintenance
[ ] Verify that all wire terminal connections are tight.
[ ] Generally inspect the unit for unusual conditions (e.g., loose access panels, leaking piping
connections, etc.)
[ ] Make sure that all retaining screws are reinstalled in the unit access panels once these checks
are complete.
Condensing Unit
WARNING
Rotating Components!
Disconnect all electric power, including remote disconnects before verifying proper fan rotation.
Follow proper lockout/tagout procedures to ensure the power can not be inadvertently
energized. Failure to disconnect power could result in fan turning on unexpectedly resulting in
death or serious injury.
[ ] Manually rotate the condenser fans to ensure free movement and check motor bearings for wear.
Verify that all of the fan mounting hardware is tight.
[ ] Verify that all wire terminal connections are tight.
[ ] Inspect the condenser coils for dirt and foreign debris. If the coils appear dirty, clean them
according to the instructions described in the “Coil Cleaning” section.
[ ] Inspect the compressor and condenser fan motor contactors. If the contacts appear severely
burned or pitted, replace the contactor. Do not clean the contacts.
[ ] Check the compressor oil level. (Compressors "Off")
Coil Cleaning
Regular coil maintenance, including annual cleaning, enhances the unit’s operating efficiency by
minimizing:
compressor head pressure and amperage draw;
evaporator water carryover;
fan brake horsepower, due to increase static pressure losses;
airflow reduction.
At least once each year, or more often if the unit is located in a “dirty” environment, clean the
evaporator and condenser coils using the instructions outlined below. Be sure to follow these
instructions as closely as possible to avoid damaging the coils.
To clean refrigerant coils, use a soft brush and a sprayer (either a garden pump-up type or a high-
pressure sprayer). A high-quality detergent is also required; suggested brands include “SPREX
A.C.”, “OAKITE 161”, “OAKITE 166” and “COILOX”. If the detergent selected is strongly alkaline (ph
value exceeds 8.5), add an inhibitor.
1. Remove enough panels from the unit to gain access to the coil.
2. Protect all electrical devices such as motors and controllers from any over spray.
3. Straighten any bent coil fins with a fin comb.
4. Mix the detergent with water according to the manufacturer’s instructions. If desired, heat the
solution to 150oF maximum to improve its cleansing capability.