Maintenance
44
RT-SVX45F-EN
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.
Note:
For units equipped with hail guards follow removal
procedure listed below.
Hail Guard Removal
•
Unlatch hail guard.
•
Pull the top of the hail guard outward until the fastener
studs are free of the retaining nuts.
•
Lift the hail guard from the lower retaining bracket and
set aside.
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 service
bulletin 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.
Note:
For more details on Microchannel coil cleaning,
please refer to bulletin RT-SVB83*-EN.
Round Tube Plate Fin (RTPF) Coils
WARNING
Hazardous Chemicals!
Failure to follow all safety instructions below 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 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.
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 BUT DO NOT EXCEED 150ºF maximum to
improve its cleansing capability.
WARNING
Hazardous Pressures!
Failure to follow safety precautions below could result
in coil bursting, which could result in death or serious
injury. Coils contain refrigerant under pressure. When
cleaning coils, maintain coil cleaning solution
temperature under 150°F to avoid excessive pressure in
the coil.
5. Pour the cleaning solution into the sprayer. If a high-
pressure sprayer is used:
a. do not allow sprayer pressure to exceed 600 psi.
b. the minimum nozzle spray angle is 15 degrees.
c. maintain a minimum clearance of 6" between the
sprayer nozzle and the coil.
d. spray the solution perpendicular (at 90 degrees) to
the coil face.
6. Spray the leaving-airflow side of the coil first; then
spray the opposite side of the coil. Allow the cleaning
solution to stand on the coil for five minutes.
7. Rinse both sides of the coil with cool, clean water.
8. Inspect both sides of the coil; if it still appears to be
dirty, repeat Steps 6 and 7.
9. Reinstall all of the components and panels removed in
Step 1 and any protective covers installed in step 2.
Note:
For units equipped with hail guards follow
reinstallation procedure listed below.
