York Rooftop Unit Y12AC04C1LABAB

Ensure power is disconnected from the unit

Verify that the unit is not in operation before starting maintenance

Pipe Plugs Removal and Cleaning

Remove both pipe plugs at each end shell

Clean out any hardened grease or foreign matter from the pipe plug openings

Replace one plug on each end with a clean grease fitting

Ensure power is disconnected from the unit

Do not lubricate bearings with the unit in operation

Check motor for accumulations of dust blocking cooling slots

Check drive components for issues

Check that all mounting bolts are tight

Replace defective parts as required

Label all wires prior to disconnection

Verify outdoor fan motors are permanently lubricated

Is lubrication desired for outdoor fan motors?

Verify vendor motors are factory lubricated for 10-year life

Verify proper operation after servicing

Review the installation for any errors, leaks, or undesirable system effects

Ensure blower speed changes are made by qualified personnel

Enter the PD of the standard sheave

Calculate the PD of the new sheave using the formula: (Specified CFM/Measured CFM) X PD of standard sheave

Select the new motor sheave based on the calculated PD and reference tables

Is the unit equipped with power exhaust fans or a return air fan?

Belt Tension Adjustment Procedure

Loosen the four bolts holding the motor base to the channels

Adjust the belt by turning nuts 'A' (see detail 'B')

Apply a perpendicular force to one belt at the midpoint of the span using a belt tension checker

Enter the deflection distance obtained (in inches)

Select the fan type and motor horsepower

Is the belt tension within the recommended deflection force range?