Carrier 50JZ ÐDefrost Mode, ÐEmergency Heat Mode, Maintenance and Service, Routine Maintenance

Table 1ÐIndoor-Air Filter Data

UNIT SIZE	024	030	036	048	060
50JZ (50HZ)
RETURN-AIR	20º x 20º	20º x 20º	20º x 24º	24º x 30º	24º x 30º
FILTERS (mm.)
	(508 x 508)	(508 x 508)	(508 x 609.6)	(609.6 x 762)	(609.6 x 762)
Throwaway

Step 4ÐDefrost Mode

When your heat pump is providing heat to your home or office and the outdoor temperature drops below 45°F/7.2°C, moisture may begin to freeze on the surface of the coil. If allowed to build up, this ice would impede airflow across the coil and reduce the amount of heat absorbed from the outside air. So, to maintain energy-efficient operation, your heat pump has an automatic defrost mode.

The defrost mode starts at a preset time interval of 30 minutes, although, it may be reset to 60, 90 or 120 minutes. Defrost will start at the preset time only if the ice is sufficient to interfere with normal heating operation.

After the ice is melted from the coil, or after a maximum of 10 minutes in defrost mode, these units automatically switch back to normal heating operation.

Do not be alarmed if steam or fog appears at the outdoor unit during defrost mode. Water vapor from the melting ice may condense into a mist in the cold outside air.

During certain weather conditions such as heavy snow and freezing rain it is not uncommon for ice to build up on the unit grille. This is normal for these weather conditions. Do not attempt to remove the ice from the unit grille. This condition will not affect the proper function of the unit and will clear within a few days.

Step 5ÐEmergency Heat Mode

This allows your supplemental heating source to keep your home or office warm until your heat pump can be serviced.

MAINTENANCE AND SERVICE

This section discusses maintenance that should be performed by your dealer and care you, as the owner, may wish to handle for your new heat pump.

ROUTINE MAINTENANCE

All routine maintenance should be handled by skilled, experienced personnel. Your dealer can help you establish a standard proce- dure.

For your safety, keep your unit area clear and free of combustible materials, gasoline, and other flammable liquids and vapors.

To assure proper functioning of your unit, flow of condenser air must not be obstructed from reaching the unit. Minimum clearance from the top of the unit is 48 in./1219 mm. Clearance of at least 36 in./914 mm is required on sides except the power entry side (42 in./1067 mm clearance) and the duct side (12 in./305 mm mini- mum clearance).

MAINTENANCE AND CARE FOR THE EQUIPMENT OWNER

1.TURN OFF ELECTRICAL POWER TO YOUR UNIT BEFORE SERVICING OR PERFORMING MAINTE- NANCE. ELECTRIC SHOCK COULD CAUSE SERI- OUS INJURY OR DEATH.

2.When removing access panels or performing maintenance functions inside your unit, be aware of sharp sheet metal parts and screws. Although special care is taken to keep sharp edges to a minimum, be extremely careful when handling parts or reaching into the unit.

Air Filters

The air filter(s) should be checked at least every 3 or 4 weeks and changed or cleaned whenever it becomes dirty. Dirty filters produce excessive stress on the blower motor and can cause the motor to overheat and shut down. Table 1 indicates the correct filter size for your unit. Refer to Fig. 2 to access the filters.

ACCESS PANEL

FILTER ACCESS

PANEL*

*For accessory filter rack.

C99094

Fig. 2ÐFilter Access Panel-Vertical Supply Shown

To replace or inspect filters (or accessory filter rack when supplied):

Before proceeding with those things you might want to maintain yourself, please carefully consider the following:

1.Remove the filter access panel using a 5/16-in. (7.9 mm) nut driver or wrench.

2.Remove the filter(s) by pulling it out of the unit. If the filter(s) is dirty, clean or replace with a new one.

When installing the new filter(s), note the direction of the airflow arrows on the filter frame.

If you have difficulty locating your air filter(s) or have questions concerning proper filter maintenance, contact your dealer for instructions. When replacing filters, always use the same size and type of filter that was supplied, originally, by the installer.

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