Foundation™ (RT-SVX069A-EN) Rooftop Units: Monthly Maintenance

Cooling Season

• Check the unit’s drain pans and condensate piping to ensure that there are no blockages.

• Inspect the evaporator and condenser coils for dirt, bent fins, etc. If the coils appear dirty, clean them according to the instructions described in “Coil Cleaning” later in this section.

• Manually rotate the condenser fans to ensure free movement and check motor bearings for wear. Verify that all of the fan mounting hardware is tight.

• Inspect the F/A-R/A damper hinges and pins to ensure that all moving parts are securely mounted. Keep the blades clean as necessary.

• Verify that all damper linkages move freely; lubricate with white grease, if necessary.

• Check supply fan motor bearings; repair or replace the motor as necessary.

• Check the fan shaft bearings for wear. Replace the bearings as necessary.

• Check the supply fan belt(s). If the belts are frayed or worn, replace them. Refer to the “Fan Belt Adjustment-Belt Drive Units,” p. 36 for belt replacement and adjustments.

• Verify that all wire terminal connections are tight.

• Remove any corrosion present on the exterior surfaces of the unit and repaint these areas.

• Generally inspect the unit for unusual conditions (e. g., loose access panels, leaking piping connections, etc.)

• Make sure that all retaining screws are reinstalled in the unit access panels once these checks are complete.

• With the unit running, check and record the: ambienttemperature; compressor suction and discharge pressures (each circuit); superheat (each circuit); Record this data on an “operator’s maintenance log” like the one shown in Table 6, p. 24. If the operating pressures indicate a refrigerant shortage, measure the system superheat. For guidelines, refer to “Compressor Start-Up,” p. 20.

With the unit running, check and record the following:

• ambient temperature

• compressor oil level (each circuit)

• compressor suction and discharge pressures (each circuit)

• superheat and subcooling (each circuit)

Heating Season

• Inspect the unit’s air filters. If necessary, clean or replace them.

• Check supply fan motor bearings; repair or replace the motor as necessary.

• Inspect both the main unit control panel and heat section control box for loose electrical components and terminal connections, as well as damaged wire insulation. Make any necessary repairs.

• Verify that the electric heat system operates properly.

Regular coil maintenance, including annual cleaning enhances the unit’s operating efficiency by minimizing the following:

• Compressor head pressure and amperage draw

• Evaporator water carryover

• Fan brake horsepower

• Static pressure losses

• Airflow reduction