Seasonal Maintenance; Return Air Filters; Removing The Return Air Filters; Re-Installing The Access Panel - Carrier WeatherMaster 50HCQ04-12 Service And Maintenance Instructions

Seasonal Maintenance

These items should be checked at the beginning of each season
(or more often if local conditions and usage patterns dictate):
AIR CONDITIONING/HEAT PUMP
• Ensure outdoor fan motor mounting bolts are tight
• Ensure compressor mounting bolts are tight
• Inspect outdoor fan blade positioning
• Ensure control box is clean
• Check control box wiring condition
• Ensure wire terminals are tight
• Check refrigerant charge level
• Ensure indoor coils are clean
• Check supply blower motor amperage
ELECTRIC HEATING
• Inspect power wire connections
• Ensure fuses are operational
• Ensure manual-reset limit switch is closed
ECONOMIZER OR OUTSIDE AIR DAMPER
• Check inlet filters condition
• Check damper travel (economizer)
• Check gear and dampers for debris and dirt
AIR FILTERS AND SCREENS
Each unit is equipped with return air filters. If the unit has an
economizer, it will also have an outside air screen. If a manual
outside air damper is added, it will also have an inlet air screen.
Each of these filters and screens will need to be periodically re-
placed or cleaned.

RETURN AIR FILTERS

CAUTION
EQUIPMENT DAMAGE HAZARD
Failure to follow this CAUTION can result in premature
wear and damage to equipment.
DO NOT OPERATE THE UNIT WITHOUT THE RE-
TURN AIR FILTERS IN PLACE.
Dirt and debris can collect on heat exchangers and coils
possibly resulting in a small fire. Dirt buildup on compo-
nents can cause excessive current used resulting in motor
failure.
Return air filters are disposable fiberglass filters. Access to the
filters is through the lift-out filter access panel located on the
rear side of the unit, above the indoor coil access panel. See
Fig. 2.

Removing the Return Air Filters

1. Grasp the bottom flange of the upper panel.
2. Lift up and swing the bottom out until the panel disen-
gages and pulls out.
3. Reach inside and remove filters from the filter rack.
4. Replace filters as required with similar replacement filters
of same size.

Re-Installing the Access Panel

1. Slide the top of the panel up under the unit top panel.
2. Slide the bottom into the side channels.
3. Push the bottom flange down until it contacts the top of
the lower panel (or economizer top).

Outside Air Hood

Outside air hood inlet screens are permanent aluminum-mesh
type filters. Check these for cleanliness. Remove the screens
when cleaning is required. Clean by washing with hot low-
pressure water and soft detergent and replace all screens before
restarting the unit. Observe the flow direction arrows on the
side of each filter frame.

Economizer Inlet Air Screen

This air screen is retained by filter clips under the top edge of
the hood. See Fig. 3.
To remove the filter, open the filter clips. Re-install the filter by
placing the frame in its track, then closing the filter clips.
DIVIDER
BAROMETRIC
RELIEF
Fig. 3 — Filter Installation

Manual Outside Air Hood Screen

The Manual Outside Air Hood Screen is secured by three
screws and a retainer angle across the top edge of the hood. See
Fig. 4.
SCREWS
Fig. 4 — Screens Installed on Outdoor-Air Hood
(Sizes A07, D08-09 Shown)
Remove the screen by loosening the three screws in the top re-
tainer and move the retainer up until the filter can be removed.
4
17 1/4"
OUTSIDE
AIR
HOOD
CLEANABLE
ALUMINUM
FILTER
FILTER
FILTER
CLIP