Carrier 50ZH024-060 - Manual (Page 16)

Inspect air filter(s) at least once each month and replace
(throwaway-type) or clean (cleanable-type) at least twice dur-
ing each cooling season or whenever the filters become clogged
with dust and lint.
Replace filters with the same dimensional size and type as
originally provided, when necessary.
Unit Top Removal (Outdoor-Coil Side)
NOTE: When performing maintenance or service proce-
dures that require removal of the unit top, be sure to
perform all of the routine maintenance procedures that re-
quire top removal, including coil inspection and cleaning,
and condensate drain pan inspection and cleaning.
Only qualified service personnel should perform mainte-
nance and service procedures that require unit top removal.
Refer to the following top removal procedures:
1. Remove 7 screws on unit top cover surface. (Save all screws.)
2. Remove 2 screws on unit top cover flange. (Save all screws.)
3. Lift top from unit carefully. Set top on edge and make
sure that top is supported by unit side that is opposite
duct (or plenum) side.
4. Carefully replace and secure unit top to unit, using screws
removed in Steps 1 and 2, when maintenance and/or serv-
ice procedures are completed.
Indoor Blower and Motor — For longer life, oper-
ating economy, and continuing efficiency, clean accumu-
lated dirt and grease from the blower wheel and motor
annually.
Disconnect and tag electrical power to the unit before
cleaning the blower wheel. Failure to adhere to this warn-
ing could cause personal injury or death.
To clean the blower wheel:
1. Access the blower assembly as follows:
a. Remove top access panel.
b. Remove 3 screws that hold blower orifice ring to blower
housing. Save screws.
c. Loosen setscrew(s) which secure wheel to motor shaft.
2. Remove and clean blower wheel as follows:
a. Lift wheel from housing. When handling and/or clean-
ing blower wheel, be sure not to disturb balance weights
(clips) on blower wheel vanes.
b. Remove caked-on dirt from wheel and housing with a
brush. Remove lint and/or dirt accumulations from wheel
and housing with vacuum cleaner, using a soft brush
attachment. Remove grease and oil with a mild
solvent.
c. Reassemble blower into housing. Place upper orifice
ring on blower to judge location of the blower wheel.
Blower wheel should be approximately 0.2-in. below
bottom of orifice ring when centered correctly. Be sure
setscrews are tightened on motor and are not on round
part of shaft.
d. Set upper orifice ring in place with 3 screws removed
in Step 1.
e. Replace top access panel.
Outdoor Coil, Indoor Coil, and Condensate Drain
Pan —
Inspect the outdoor coil, indoor coil, and conden-
sate drain pan at least once each year. Proper inspection and
cleaning requires the removal of the unit top. See Unit Top
Removal section above.
The coils are easily cleaned when dry; therefore, inspect
and clean the coils either before or after each cooling sea-
son. Remove all obstructions (including weeds and shrubs)
that interfere with the airflow through the outdoor coil.
Straighten bent fins with a fin comb. If coated with dirt or
lint, clean the coils with a vacuum cleaner, using a soft brush
attachment. Be careful not to bend the fins. If coated with oil
or grease, clean the coils with a mild detergent-and-water
solution. Rinse coils with clear water, using a garden hose.
Be careful not to splash water on motors, insulation, wiring,
or air filter(s). For best results, spray outdoor-coil fins from
inside to outside the unit. Be sure to clean between the coils.
Be sure to flush all dirt and debris from the unit base.
Inspect the drain pan and condensate drain line when in-
specting the coils. Clean the drain pan and condensate drain
by removing all foreign matter from the pan. Flush the pan
and drain tube with clear water. Do not splash water on the
insulation, motor, wiring, or air filter(s). If the drain tube is
restricted, clear it with a ‘‘plumbers snake’’ or similar probe
device. Ensure that the auxiliary drain port above the drain
tube is also clear.
Outdoor Fan
Keep the outdoor fan free from all obstructions to en-
sure proper cooling operation. Never place articles on
top of the unit. Damage to unit may result.
1. Shut off unit power supply.
2. Remove outdoor-fan assembly (grille, motor, motor cover,
and fan) by removing screws and flipping assembly onto
unit top cover.
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig. 21A and 21B.
5. Tighten setscrews.
6. Replace outdoor-fan assembly.
Electrical Controls and Wiring — Inspect and check
the electrical controls and wiring annually. Be sure to turn
off the electrical power to the unit.
Remove the top panel to locate all the electrical controls
and wiring. Check all electrical connections for tightness.
Tighten all screw connections. If any smoky or burned con-
nections are noticed, disassemble the connection, clean all
the parts, restrip the wire end and reassemble the connection
properly and securely.
After inspecting the electrical controls and wiring, re-
place all the panels. Start the unit, and observe at least one
complete cooling cycle to ensure proper operation. If dis-
crepancies are observed in operating cycle, or if a suspected
malfunction has occurred, check each electrical component
with the proper electrical instrumentation. Refer to the unit
wiring label when making these checkouts.
NOTE: Refer to the Sequence of Operation section on
page 15, as an aid in determining proper control operation.
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