Carrier 48XL Maintenance, Air Filter, Indoor Fan and Motor, Limit Switch, Burner Ignition

MAINTENANCE

To ensure continuing high performance, and to minimize the possibility of premature equipment failure, periodic maintenance must be performed on this equipment. This packaged unit should be inspected at least once each year by a qualified service person. To troubleshoot unit, refer to Table 10, Troubleshooting Chart.

NOTE TO EQUIPMENT OWNER: Consult your local dealer about the availability of a maintenance contract.

PERSONAL INJURY AND UNIT DAMAGE HAZARD

Failure to follow this warning could result in personal injury or death and possible unit component damage.

The ability to properly perform maintenance on this equipment requires certain expertise, mechanical skills, tools and equipment. If you do not possess these, do not attempt to perform any maintenance on this equipment, other than those procedures recommended in the Owner's Manual.

ELECTRICAL SHOCK HAZARD

Failure to follow these warnings could result in personal injury or death:

1.Turn off electrical power to the unit before performing

any maintenance or service on this unit.

2.Use extreme caution when removing panels and parts.

3.Never place anything combustible either on or in contact with the unit.

[]NIT OPERATION HAZARD

Failure to follow this caution may result in equipment damage or improper operation.

Errors made when reconnecting wires may cause improper

and dangerous operation. Label all wires prior to disconnecting when servicing.

The minimum maintenance requirements for this equipment are as follows:

1.Inspect air filter(s) each month. Clean or replace when necessary.

2.Inspect indoor coil, drain pan, and condensate drain each cooling season for cleanliness. Clean when necessary.

3.Inspect indoor fan motor and wheel for cleanliness each cooling season. Clean when necessary.

4.Check electrical connections for tightness and controls for proper operation each cooling season. Service when necessary.

5.Check for restrictions on inducer outlet. Clean flue hood.

6.Inspect burner compartment before each heating season for rust, corrosion, soot or excessive dust.

7.Inspect all accessories. Perform any service or maintenance to the accessories as recommended in the accessory instructions.

Air Filter

IMPORTANT: Never operate the unit without a suitable air filter in the return-air duct system. Always replace the filter with the

same dimensional size and type as originally installed. See Table 1 for recommended filter sizes.

Inspect air filter(s) at least once each month and replace (throwaway-type) or clean (cleanable-type) at least twice during each cooling season and twice during the heating season, or whenever the filter becomes clogged with dust and lint.

Indoor Fan and Motor

NOTE: All motors are pre-lubricated. Do not attempt to lubricate these motors.

For longer life, operating economy, and continuing efficiency, clean accumulated dirt and grease from the blower wheel and motor annually.

Inducer Blower

NOTE: All motors are pre-lubricated. Do not attempt to lubricate these motors.

Clean periodically to assure proper airflow and heating efficiency. Inspect blower wheel every fall and periodically during the heating season. For the first heating season, inspect blower wheel bi-monthly to determine proper cleaning frequency.

Limit Switch

Remove unit access panel to gain access to the limit switch. The limit switch is located above the indoor blower housing.

NOTE: On small chassis units, a second limit switch is located beside the indoor blower housing.

Burner Ignition

[]nit is equipped with a direct spark ignition 100 percent lockout system. Ignition module is located in the control box. Refer to additional information in the Start-Up & Troubleshooting section for Status Code information.

Main Burners

At the beginning of each heating season, inspect for deterioration or blockage due to corrosion or other causes. Observe the main burner flames and adjust, if necessary.

EQUIPMENT DAMAGE HAZARD

Failure to follow this caution may result in equipment damage or improper operation.

When servicing gas train, do not hit or plug orifice spuds.

Removal of Gas Train

To remove the gas train for servicing:

1.Shut off main gas valve.

2.Shut off power to unit.

3.Remove unit access panel.

4.Disconnect gas piping at unit gas valve.

5.Remove wires connected to gas valve. Mark each wire.

6.Remove ignitor and sensor wires at the ignitor module.

7.Remove the mounting screw that attaches the burner rack to the unit base.

8.Slide the burner rack out of the unit.

9.To reinstall, reverse the procedure outlined above.

Inducer Pressure Switch

Inspect pressure switch connections. Inspect pressure switch tube for cracks or restrictions. Replace if needed.

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