Unit Arrangement And Access; General; Maintenance; Routine Maintenance - Carrier WeatherMaster 48HC04 Service And Maintenance Instructions

IMPORTANT: OPERATIONAL TEST ALERT
Failure to follow this ALERT can result in an unnecessary
evacuation of the facility.
Pressing the controller's test/reset switch for longer than
seven seconds will put the duct detector into the alarm state
and activate all automatic alarm responses.
IMPORTANT: Lockout/tag-out is a term used when elec-
trical power switches are physically locked preventing
power to the unit. A placard is placed on the power switch
alerting service personnel that the power is disconnected.

UNIT ARRANGEMENT AND ACCESS

General

Figures 1 and 2 show general unit arrangement and access
locations.
FILTER ACCESS PANEL
Fig. 1 — Typical Access Panel Locations
COMPRESSOR
(08-09 only)
Fig. 2 — Blower Access Panel Location

MAINTENANCE

Routine Maintenance

These items should be part of a routine maintenance program, to
be checked every month or two, until a specific schedule for each
can be identified for this installation.
Quarterly Inspection (and 30 days after initial start)
• Return air filter replacement
• Outdoor hood inlet filters cleaned
• Belt tension checked
• Belt condition checked
• Pulley alignment checked
• Fan shaft bearing locking collar tightness checked
COMPRESSOR
ACCESS PANEL (04-07 only)
OUTDOOR-AIR OPENING AND
INDOOR COIL ACCESS PANEL
BLOWER
ACCESS
PANEL
FLUE OPENING
CONTROL BOX
• Condenser coil cleanliness checked
• Condensate drain checked

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
• Condenser fan motor mounting bolts tightness
• Compressor mounting bolts
• Condenser fan blade positioning
• Control box cleanliness and wiring condition
• Wire terminal tightness
• Refrigerant charge level
• Evaporator coil cleaning
• Evaporator blower motor amperage
HEATING
• Heat exchanger flue passageways cleanliness
• Gas burner condition
• Gas manifold pressure
• Heating temperature rise
ECONOMIZER OR OUTSIDE AIR DAMPER
• 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 econ-
omizer, it will also have an outside air screen. If a manual outside
air damper is added, an inlet air screen will also be present.
Each of these filters and screens will need to be periodically re-
placed or cleaned.

RETURN AIR FILTERS

EQUIPMENT DAMAGE HAZARD
Failure to follow this CAUTION can result in premature wear
and damage to equipment.
DO NOT OPERATE THE UNIT WITHOUT THE RETURN
AIR FILTERS IN PLACE.
Dirt and debris can collect on heat exchangers and coils possi-
bly resulting in a small fire. Dirt buildup on components can
cause excessive current used resulting in motor failure.
Return air filters are disposable fiberglass media type. Access to
the filters is through the small lift-out panel located on the rear
side of the unit, above the evaporator/return air access panel. (See
Fig. 1.)
To remove the 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 extract the filters from the filter rack.
4. Replace these filters as required with similar replacement
filters of same size.
3
CAUTION