Carrier 50LC 14, Service And Maintenance Instructions

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3. Divide that number by the number of pulley turns open
from full closed.
This number is the change in pitch datum per turn open.
EXAMPLE
• Pulley dimensions 2.9 to 3.9 (full close to full open)
• 3.9 – 2.9 = 1
• 1 divided by 5 (turns from full close to full open)
• 0.2 change in pulley diameter per turn open
• 2.9 + 0.2 = 3.1-in. pulley diameter when pulley closed one
turn from full open
COOLING
Evaporator Coil
The evaporator coil is traditional round-tube, plate-fin technol-
ogy. Tube and fin construction is of various optional materials
and coatings (see Appendix A). Coils are multiple-row. On two
compressor units, the evaporator coil is a face split design,
meaning the two refrigerant circuits are independent in the
coil. The bottom portion of the coil will always be circuit A,
with the top of the coil being circuit B.
Coil Maintenance and Cleaning Recommendation
Routine cleaning of coil surfaces is essential to maintain proper
operation of the unit. Elimination of contamination and remov-
al of harmful residues will greatly increase the life of the coil
and extend the life of the unit. The following maintenance and
cleaning procedures are recommended as part of the routine
maintenance activities to extend the life of the coil.
REMOVE SURFACE LOADED FIBERS
Surface loaded fibers or dirt should be removed with a vacuum
cleaner. If a vacuum cleaner is not available, a soft non-metal-
lic bristle brush may be used. In either case, the tool should be
applied in the direction of the fins. Coil surfaces can be easily
damaged (fin edges can be easily bent over and damage to the
coating of a protected coil) if the tool is applied across the fins.
NOTE: Use of a water stream, such as a garden hose, against a
surface loaded coil will drive the fibers and dirt into the coil. This
will make cleaning efforts more difficult. Surface loaded fibers
must be completely removed prior to using low velocity clean wa-
ter rinse.
PERIODIC CLEAN WATER RINSE
A periodic clean water rinse is very beneficial for coils that are
applied in coastal or industrial environments. However, it is
very important that the water rinse is made with very low ve-
locity water stream to avoid damaging the fin edges. Monthly
cleaning as described below is recommended.
ROUTINE CLEANING OF EVAPORATOR COIL SURFACES
Monthly cleaning with Totaline environmentally sound coil
cleaner is essential to extend the life of coils. This cleaner is
available from Carrier Replacement parts division as part
number P902-0301 for one gallon container, and part number
P902-0305 for a 5 gallon container. It is recommended that all
round tube coil cleaner as described below. Coil cleaning
should be part of the unit’s regularly scheduled maintenance
procedures to ensure long life of the coil. Failure to clean the
coils may result in reduced durability in the environment.
Avoid the use of
• coil brighteners
• acid cleaning prior to painting
• high pressure washers
• poor quality water for cleaning
Totaline environmentally sound coil cleaner is non-flammable,
hypoallergenic, non-bacterial, and a USDA accepted biode-
gradable agent that will not harm coil or surrounding compo-
nents such as electrical wiring, painted metal surfaces, or insu-
lation. Use of non-recommended coil cleaners is strongly dis-
couraged since coil and unit durability could be affected.
Totaline Environmentally Sound Coil Cleaner Application
Equipment
• 2 1 /
2
gallon garden sprayer
• water rinse with low velocity spray nozzle
Totaline Environmentally Sound Coil Cleaner Application
Instructions
1. Proper eye protection such as safety glasses, gloves and
protective clothing are recommended during mixing and
application.
2. Remove all surface loaded fibers and dirt with a vacuum
cleaner as described above.
3. Thoroughly wet finned surfaces with clean water and a
low velocity garden hose, being careful not to bend fins.
4. Mix Totaline environmentally sound coil cleaner in a
2 1 /
2
gallon garden sprayer according to the instructions
included with the cleaner. The optimum solution tempera-
ture is 100°F (38°C).
NOTE: Do NOT use water in excess of 130°F (54°C), as the enzy-
matic activity will be destroyed.
5. Thoroughly apply Totaline environmentally sound coil
cleaner solution to all coil surfaces including finned area,
tube sheets and coil headers.
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal injury,
death and/or equipment damage.
This system uses R-410A refrigerant, which has higher
pressures than R-22 and other refrigerants. No other refrig-
erant may be used in this system. Gage set, hoses, and re-
covery system must be designed to handle R-410A refriger-
ant. If unsure about equipment, consult the equipment man-
ufacturer.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in accelerated cor-
rosion of unit parts.
Harsh chemicals, household bleach or acid or basic clean-
ers should not be used to clean outdoor or indoor coils of
any kind. These cleaners can be very difficult to rinse out of
the coil and can accelerate corrosion at the fin/tube inter-
face where dissimilar materials are in contact. If there is
dirt below the surface of the coil, use the environmentally
balanced coil cleaner.
CAUTION
UNIT DAMAGE HAZARD
Failure to follow this caution may result in reduced unit
performance or unit shutdown.
High velocity water from a pressure washer, garden hose,
or compressed air should never be used to clean a coil. The
force of the water or air jet will bend the fin edges and in-
crease airside pressure drop.