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4
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
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.
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 — 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.
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.
17 1/4”
DIVIDER
BAROMETRIC
RELIEF
CLEANABLE
ALUMINUM
FILTER
FILTER
HOOD
FILTER
CLIP
OUT
S
IDE
AIR
SCREWS
Summary of Contents for 50HCQ04---12
Page 86: ...86 APPENDIX E WIRING DIAGRAMS cont Fig C 50HCQA04 A05 Control Wiring Diagram 575 3 60...
Page 88: ...88 APPENDIX E WIRING DIAGRAMS cont Fig E 50HCQ 06 Control Wiring Diagram 575 3 60...
Page 93: ...93 APPENDIX E WIRING DIAGRAMS cont Fig J 50HCQ 04 05 06 Power Wiring Diagram 208 230 1 60...
Page 94: ...94 APPENDIX E WIRING DIAGRAMS cont Fig K 50HCQ 04 05 06 Power Wiring Diagram 208 230 3 60...
Page 95: ...95 APPENDIX E WIRING DIAGRAMS cont Fig L 50HCQ 04 05 06 Power Wiring Diagram 460 3 60...
Page 96: ...96 APPENDIX E WIRING DIAGRAMS cont Fig M 50HCQ 04 05 06 Power Wiring Diagram 575 3 60...
Page 100: ...100 APPENDIX E WIRING DIAGRAMS cont Fig Q 50HCQ 12 Power Wiring Diagram 208 230 3 60...
Page 101: ...101 APPENDIX E WIRING DIAGRAMS cont Fig R 50HCQ 12 Power Wiring Diagram 460 3 60 575 3 60...
Page 102: ...102 APPENDIX E WIRING DIAGRAMS cont Fig S 50HCQ PremierLink Control Diagram...
Page 103: ...103 APPENDIX E WIRING DIAGRAMS cont Fig T 50HCQ RTU Open Control Diagram...