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SERVICE
Perform the procedures outlined below periodically, as indicated.
An annual "checkup" is recommended by a licensed refrigeration
mechanic. Recording the performance measurements of volts,
amps, and water temperature differences (both heating and cool-
ing) is recommended. This data should be compared to the infor-
mation on the unit's data plate and the data taken at the original
startup of the equipment.
Periodic lockouts almost always are caused by air or water flow
problems. The lockout (shutdown) of the unit is a normal protec-
tive measure in the design of the equipment. If continual lock-outs
occur, call a mechanic immediately and have them check for: wa-
ter flow problems, water temperature problems, air flow problems
or air temperature problems. Use of the pressure and temperature
charts for the unit may be required to properly determine the
cause.
IMPORTANT: When a compressor is removed from this unit,
system refrigerant circuit oil will remain in the compressor. To
avoid leakage of compressor oil, the refrigerant lines of the
compressor must be sealed after it is removed.
IMPORTANT: All refrigerant discharged from this unit must be
recovered without exception. Technicians must follow industry
accepted guidelines and all local, state and federal statutes for the
recovery and disposal of refrigerants.
CAUTION
To avoid the release of refrigerant into the atmosphere, the
refrigerant circuit of this unit must only be serviced by
technicians which meet local, state and federal proficiency
requirements.
WARNING
To prevent injury or death due to electrical shock or contact
with moving parts, open unit disconnect switch before
servicing unit.
Filters
Filter changes or cleanings are required at regular intervals. The
time period between filter changes will depend upon the type of
environment the equipment is used in. In a single family home that
is not under construction, changing or cleaning the filter every
60 days may be sufficient. In other applications such as motels,
where daily vacuuming produces a large amount of lint, filter
changes may need to be as frequent as biweekly. See Fig. 2-5 for
replacement filter sizes.
IMPORTANT: Units should never be operated without a filter.
Water Coil
Keep all air out of the water coil. Check open loop systems to be
sure the well head is not allowing air to infiltrate the water line.
Always keep lines airtight.
Inspect heat exchangers regularly, and clean more frequently if the
unit is located in a "dirty" environment. The heat exchanger
should be kept full of water at all times. Open loop systems should
have an inverted P trap placed in the discharge line to keep water
in the heat exchanger during off cycles. Closed loop systems must
have a minimum of 15 psig during the summer and 40 psig during
the winter.
Check P trap frequently for proper operation.
IMPORTANT: To avoid fouled machinery and extensive unit
clean-up, DO NOT operate units without filters in place.
DO NOT use equipment as a temporary heat source during
construction.
Condensate Drain Pans
The condensate drain should be checked annually by cleaning and
flushing to ensure proper drainage.
Check condensate drain pans for algae growth twice a year. If al-
gae growth is apparent, consult a water treatment specialist for
proper chemical treatment. Applying an algaecide every 3 months
will typically eliminate algae problems in most locations.
Refrigerant System
Verify air and water flow rates are at proper levels before servic-
ing. To maintain sealed circuitry integrity, do not install service
gauges unless unit operation appears abnormal.
Check to see that unit is within the superheat and subcooling tem-
perature ranges. If the unit is not within these ranges, recover and
reweigh in refrigerant charge.
Compressor
Conduct annual amperage checks to ensure that amp draw is no
more than 10% greater than indicated on the serial plate data.
Fan Motor Lubrication
The fan motor was properly lubricated at the time of manufacture.
Lubricate the fan motor(s) with SAE-20 (Society of Automotive
Engineers) non-detergent electric oil.
Fan Bearing Lubrication
Inspect the fan bearings for proper lubrication every 6 month or
2500 hours of operation, whichever comes first. Standard units
have grease fittings on the fan shaft bearings, located on each side
of the blower wheel. Lubricate bearings with a lithium-based
grease (NLGI Grade 2).
Condensate Drain Cleaning
Clean the drain line and unit drain pan at the start of each cooling
season. Check flow by pouring water into drain. Be sure trap is
filled to maintain an air seal.
Air Coil Cleaning
Remove dirt and debris from evaporator coil as required by condi-
tion of the coil. Clean coil with a stiff brush, vacuum cleaner, or
compressed air. Use a fin comb of the correct tooth spacing when
straightening mashed or bent coil fins.
Condenser Cleaning
Water-cooled condensers may require cleaning of scale (water de-
posits) due to improperly maintained closed-loop water systems.
Sludge build-up may need to be cleaned in an open water tower
system due to induced contaminants.
Local water conditions may cause excessive fouling or pitting of
tubes. Condenser tubes should therefore be cleaned at least once a
year, or more often if the water is contaminated.
Proper water treatment can minimize tube fouling and pitting. If
such conditions are anticipated, water treatment analysis is recom-
mended. Refer to the Carrier System Design Manual, Part 5, for
general water conditioning information.
Follow all safety codes. Wear safety glasses and rubber gloves
when using inhibited hydrochloric acid solution. Observe and
follow acid manufacturer's instructions. Failure to follow
these safety precautions could result in personal injury or
equipment or property damage.
58
CAUTION
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