Coil Cleaning - Trane RRU150F N Series Installation, Operation And Maintenance Manual

Maintenance

Coil Cleaning

WARNING
Hazardous Chemicals!
Failure to follow this safety precaution could result in
death or serious injury. Coil cleaning agents can be
either acidic or highly alkaline and can burn severely if
contact with skin or eyes occurs.
Handle chemical carefully and avoid contact with skin.
ALWAYS wear Personal Protective Equipment (PPE)
including goggles or face shield, chemical resistant
gloves, boots, apron or suit as required. For personal
safety refer to the cleaning agent manufacturer's
Materials Safety Data Sheet and follow all
recommended safe handling practices.
Units with Formed Coil Bends
The outdoor coils on all air conditioning equipment will
need periodic cleaning. The construction of the outdoor
coils of the units is somewhat different than normally
anticipated. On multi-row coils, starting from the coil
manifold end, construction consists of a section (slab) of
multi-row fins up to the coil bend and a section of single
row fins in and after the bend. The single row fins are held
apart by a piece of formed sheet metal acting as the end
support. This construction was adopted to make it
possible to clean the outdoor coil without removing the
roof of the unit. To thoroughly clean these coils the
following procedure can be used:
WARNING
Hazardous Voltage w/Capacitors!
Failure to disconnect power and discharge capacitors
before servicing could result in death or serious injury.
Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/
tagout procedures to ensure the power cannot be
inadvertently energized. Verify with an appropriate
voltmeter that all capacitors have discharged.
1. Ensure that power to the unit is turned "OFF".
2. Remove the outdoor section access panel.
3. Remove small access panel on top of outdoor coil
section to expose the separated coils.
4. Straighten coil fins with fin rake if necessary.
5. Use a soft brush to remove base debris from both sides
of the coil.
6. The coil is now ready for the cleaning application: The
wash solution is best applied first in reverse direction
of the airflow by back flushing in a downward direction
and then in the direction of the airflow in a downflow
direction.
7. Washing the coil in a downward fashion through the
outdoor coil access panel opening located over the
42
separated coil fins will flush any debris from between
the rows of fin.
8. Turn power back on to the unit.
This procedure can be followed annually if needed to
maintain adequate condenser airflow. Chemicals
Required: High Quality Detergent.
Note: If the detergent is strongly alkaline (more than
8.5 pH) after mixing, it must contain an inhibitor.
Suggested detergent brand is "COILOX" (part
number CHM00051).
Evaporator and General Coil Cleaning
Procedures for Slab Coils
WARNING
Hazardous Voltage w/Capacitors!
Failure to disconnect power and discharge capacitors
before servicing could result in death or serious injury.
Disconnect all electric power, including remote
disconnects and discharge all motor start/run
capacitors before servicing. Follow proper lockout/
tagout procedures to ensure the power cannot be
inadvertently energized. Verify with an appropriate
voltmeter that all capacitors have discharged.
1. Disconnect unit power.
2. Remove enough panels and parts to gain access to the
coil.
3. Straighten coil fins with a fin rake if necessary.
4. Use a soft brush to remove loose debris from both
sides of the coil.
5. Mix detergent with water according to the
manufacturers instructions.
The mixed solution may be heated to a maximum of 150°F
to improve its cleansing action.
NOTICE
Equipment Damage!
Do not heat the detergent-and-water solution above
150°F. Hot liquids sprayed on the exterior of the coil will
raise the coil's internal pressure and could cause it to
burst.
6. Place the mixed solution in the sprayer. If a high-
pressure sprayer is used, note the following:
a. Minimum nozzle spray angle of 15°.
b. Spray perpendicular to the coil face.
c. Keep the nozzle at least 6 inches from the coil.
d. Do not exceed 600 psi.
7. Spray the leaving side of the coil first, then the entering
air side. Allow the solution to stand on the coil for
5 minutes.
8. Rinse both sides of the coil with cool, clean water.
RRU-SVX02F-EN