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RT-SVX074A-EN
terminal connections, as well as damaged wire
insulation. Make any necessary repairs.
•
Verify that the electric heat system operates properly.
Coil Cleaning
Regular coil maintenance, including annual cleaning,
enhances the unit’s operating efficiency by minimizing the
following:
•
Compressor head pressure and amperage draw
•
Evaporator water carryover
•
Fan brake horsepower
•
Due to increase static pressure losses
•
Airflow reduction
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.
At least once each year, or more often if the unit is located
in a “dirty” environment, clean the condenser coils using
the instructions outlined below. Be sure to follow these
instructions as closely as possible to avoid damaging the
coils.
Note:
For units equipped with hail guards follow removal
procedure listed below.
Hail Guard Removal
•
Remove shipping screws (ones without washers).
•
Lift hail guards up so screws with washers go to top of
keyhole.
•
Remove hailguard by sliding washer head screw
through keyhole.
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.
Microchannel (MCHE) Coils
NOTICE
Coil Damage!
Failure to follow instructions below could result in
coil damage.
DO NOT use any detergents with microchannel
condenser coils.
Use pressurized water or air ONLY, with pressure no
greater than 600psi.
For additional information regarding the proper
microchannel coil cleaning procedure, refer to RT-
SVB83*-EN
Due to the soft material and thin walls of the MCHE coils,
the traditional field maintenance method recommended for
Round Tube Plate Fin (RTPF) coils does not apply to
microchannel coils. Moreover, chemical cleaners are a risk
factor to MCHE due to the material of the coil. The
manufacturer does not recommend the use of chemical
cleaners to clean microchannel coils. Using chemical
cleaners could lead to warranty claims being further
evaluated for validity and failure analysis.
The recommended cleaning method for microchannel
condenser coils is pressurized water or air with a non-
pinpoint nozzle and an ECU of at least 180 with pressure
no greater than 600 psi. To minimize the risk of coil
damage, approach the cleaning of the coil with the
pressure washer aimed perpendicular to the face of the coil
during cleaning.
Note:
For more details on microchannel coil cleaning,
please refer to bulletin RT-SVB83*-EN.
Hail Guard Reinstallation
Reinstall hail guards by aligning the keyholes over the
washer screw heads, and slide into place. If your
installation requires seismic or special wind load
compliance, reinstall shipping screws.
Hot Gas Reheat Additional Oil
NOTICE
Compressor Damage!
Use of incorrect refrigerant and oil could result in
compressor damage and improper unit operation.
Use only refrigerant and oil specified on the unit
nameplate.
Additional refrigerant oil has been added in the factory for
all Hot Gas Reheat units. If major components (MCHE coil,
valve assembly, etc.) are replaced or serviced, the
following steps must be taken:
1. Measure the amount of oil removed during servicing.
2. When recharging the unit after servicing, replace the
amount of oil removed, as measured in step 1. Verify oil
added is the correct type.
Summary of Contents for Precedent THJ072
Page 59: ...RT SVX074A EN 59 Notes...
