Carrier WEATHERMASTER 48/50Z030-105 - Manual (Page 125)

125
SERVICE
Service Access — All unit components can be reached
through clearly labeled hinged access doors. These doors are
not equipped with tiebacks, so if heavy duty servicing is need-
ed, either remove them or prop them open to prevent accidental
closure.
Each door is held closed with 3 latches. The latches are
secured to the unit with a single 1 /
4
-in. –20 x 1 /
2
-in. long bolt.
See Fig. 34.
To open, loosen the latch bolt using a 7 /
16
-in. wrench. Pivot
the latch so it is not in contact with the door. Open the door. To
shut, reverse the above procedure.
NOTE: Disassembly of the top cover may be required under
special service circumstances. It is very important that the ori-
entation and position of the top cover be marked on the unit
prior to disassembly. This will allow proper replacement of the
top cover onto the unit and prevent rainwater from leaking into
the unit.
COMPRESSORS
Sizes 030-050 — Access to the compressors is through the
doors on the condenser end of the unit. This door also provides
access to the discharge and suction service valves, the crank-
case heaters, and the high-pressure and low-pressure switches.
Compressor no. 1 is always the compressor on the left when
facing main control box.
Sizes 055-105 — The oil pump end (compressor access) of
each compressor is readily accessible from sides of unit. Access
the motor end of the compressor through the condenser end of the
unit or by removing compressor.
LIQUID SERVICE VALVES, FILTER DRIERS, AND
SIGHT GLASSES
Sizes 030-050 — Access to these components is through the
access panel on the right side of the unit. See Fig. 35. There is
also a Schrader port in each suction line that is accessible
through this same panel. When charging unit, route service line
through the round holes and replace panel to minimize air
bypass.
Sizes 055-105 — Access to these components is from the side
of the unit.
SUPPLY-FAN MOTORS, PULLEYS, AND BELTS — Ac-
cess to these components is through the 2 doors labeled FAN
SECTION on each side of the unit.
POWER EXHAUST MOTORS, PULLEYS, AND BELTS —
Access to these components is through the door below the side
economizer hoods on both sides of the unit. See Fig. 36.
RETURN AIR FILTERS — Access to these filters is through
the door marked FILTER SECTION.
UNIT CONTROL BOX — Access to this component is
through the doors marked ELECTRICAL SECTION on the
condenser end of the unit.
GAS HEAT SECTION (48Z Only) — Access to the gas heat
section is through the door labeled HEAT SECTION on the
right side of the unit (when facing return air end). See Fig. 37
and 38.
All gas system components are in the gas section.
MAIN BURNERS (48Z Only) — At the beginning of each
heating season, inspect for deterioration due to corrosion or
other causes. Observe the main burner flames and adjust if nec-
essary. See Gas System Adjustment section on page 131.
FLUE GAS PASSAGEWAYS (48Z Only) — The flue col-
lector box and heat exchanger cells may be inspected by
removing heat exchanger access panel, flue box cover, and
main burner assembly (Fig. 39). Refer to Main Burners
Removal and Replacement section on page 131 for burner
removal sequence. If cleaning is required, remove heat
exchanger baffles and clean tubes with a wire brush.
Use caution with ceramic heat exchanger baffles. When in-
stalling retaining clip, be sure the center leg of the clip extends
inward toward baffle. See Fig. 40.
COMBUSTION-AIR BLOWERS (48Z Only) — Clean peri-
odically to assure proper airflow and heating efficiency.
Inspect blower wheel every fall and periodically during heat-
ing season. For the first heating season, inspect blower wheel
bi-monthly to determine proper cleaning frequency.
To inspect blower wheel, remove heat exchanger access
panel. Shine a flashlight into opening to inspect wheel. If clean-
ing is required, remove motor and wheel assembly by remov-
ing screws holding motor mounting plate to top of combustion
fan housing (Fig. 41). The motor and wheel assembly will slide
up and out of the fan housing. Remove the blower wheel from
the motor shaft and clean with a detergent or solvent. Replace
motor and wheel assembly.
ECONOMIZER DAMPER MOTOR(S) — On units so
equipped, the economizer motor(s) is located in the mixing
box section. Access to it is through the door labeled FILTER
SECTION.
CONDENSER FANS AND FAN MOTORS — Remove the
wire fan guard on top of the unit to gain access to the condenser
fans and motors.
INLET GUIDE VANE MOTOR — The inlet guide vane mo-
tor is located on the evaporator-fan sled on the side opposite the
fan motor. See Fig. 42A and 42B. Access is through the door
labeled FAN SECTION.
25% OUTDOOR-AIR DAMPER — Access to adjust the
damper is through the hoods. Remove filters to gain access into
unit to adjust linkage arms.
MODULATING POWER EXHAUST DAMPER MOTOR —
The modulating power exhaust damper motor is located in the
return-air end of the unit.
The motor is accessed through the small door below the side
economizer hoods on the left side of the unit. See Fig. 36.
RETURN-AIR FILTERS — Access to these filters is through
the door marked FILTER SECTION. Filters in upper and low-
er bag filter tracks can only be removed from the right side of
the unit.
IMPORTANT: After servicing is completed, make sure
door is closed and relatched properly, and that the
latches are tight. Failure to do this can result in water
leakage into the indoor-air section of the unit.
IMPORTANT: When replacing panel, be sure to prop-
erly secure it in order to prevent water from being drawn
into the unit.