American Standard YHC033A, Установка, эксплуатация и обслуживание

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Return Air Smoke Detector Maintenance
Airflow through the unit is affected by the amount of dirt and
debris accumulated on the indoor coil and filters. To insure
that airflow through the unit is adequate for proper sampling by
the return air smoke detector, complete adherence to the main-
tenance procedures, including recommended intervals be-
tween filter changes, and coil cleaning is required.
Periodic checks and maintenance procedures must be per-
formed on the smoke detector to insure that it will function
properly. For detailed instructions concerning these checks
and procedures, refer to the appropriate section(s) of the
smoke detector Installation and Maintenance Instructions
provided with the literature package for this unit.
Cooling Season
[ ] Check the unit’s drain pans and condensate piping to en-
sure that there are no blockages.
[ ] Inspect the evaporator and condenser coils for dirt, bent
fins, etc. If the coils appear dirty, clean them according to
the instructions described in “Coil Cleaning” later in this
section.
[ ] Manually rotate the condenser fan(s) to ensure free
movement and check motor bearings for wear. Verify that
all of the fan mounting hardware is tight.
[ ] Inspect the F/A-R/A damper hinges and pins to ensure
that all moving parts are securely mounted. Keep the
blades clean as necessary.
[ ] Verify that all damper linkages move freely; lubricate with
white grease, if necessary.
[ ] Check supply fan motor bearings; repair or replace the
motor as necessary.
[ ] Check the fan shaft bearings for wear. Replace the bear-
ings as necessary.
[ ] Check the supply fan belt. If the belt is frayed or worn, re-
place it. Refer to the “Fan Belt Adjustment” section for belt
replacement and adjustments.
[ ] Verify that all wire terminal connections are tight.
[ ] Remove any corrosion present on the exterior surfaces of
the unit and repaint these areas.
[ ] Generally inspect the unit for unusual conditions (e.g.,
loose access panels, leaking piping connections, etc.)
[ ] Make sure that all retaining screws are reinstalled in the
unit access panels once these checks are complete.
[ ] With the unit running, check and record the: ambient tem-
perature; compressor suction and discharge pressures
(each circuit); superheat (each circuit);
Record this data on an “operator’s maintenance log” like the
one shown in Table 8. If the operating pressures indicate a
refrigerant shortage, measure the system superheat. For
guidelines, refer to the “Compressor Start-Up” section.
Maintenance
Note: Do Not release refrigerant to the atmosphere!
If adding or removing refrigerant is required, the
service technician must comply with all federal,
state and local laws.
Heating Season
[ ] Inspect the unit’s air filters. If necessary, clean or replace
them.
[ ] Check supply fan motor bearings; repair or replace the
motor as necessary.
[ ] Inspect both the main unit control panel and heat section
control box for loose electrical components and terminal
connections, as well as damaged wire insulation. Make
any necessary repairs.
[ ] Clean burner area, verify gas heat system operates prop-
erly.
Coil Cleaning
Regular coil maintenance, including annual cleaning, en-
hances the unit’s operating efficiency by minimizing: com-
pressor head pressure and amperage draw; evaporator wa-
ter 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 (ei-
ther 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.