York Rooftop Unit ZH150C00D5B1BAA1A1

1. Remove the dot plugs from the duct panel (see Figures 12 and 13 for location)

2. Insert eight inches of 1/4 inch metal tubing into the airflow on both sides of the indoor coil

The tubes must be inserted and held in a position perpendicular to the air flow so that velocity pressure will not affect the static pressure readings

3. Use an Inclined Manometer or Magnehelic to determine the pressure drop across a dry evaporator coil

Measuring the pressure drop across a wet coil under field conditions could be inaccurate

To assure a dry coil, the compressors should be de-activated while the test is being run

CAUTION: Only qualified personnel should make blower speed changes, strictly adhering to the fan laws.

Before making any blower speed changes review the installation for any installation errors, leaks or undesirable systems effects that can result in loss of airflow.

Even small changes in blower speed can result in substantial changes in static pressure and BHP.

BHP and AMP draw of the blower motor will increase by the cube of the blower speed.

Static pressure will increase by the square of the blower speed.

Enter the measured CFM at unit start-up.

Enter the existing datum diameter (DD) of the variable pitch motor sheave.

Enter the new datum diameter (DD) calculated using the formula: Required CFM / Measured CFM × Existing DD = New DD.

CAUTION: This procedure requires trained personnel with PPE!

PROCEDURE FOR ADJUSTING BELT TENSION

Loosen the four bolts holding the motor base to the channels

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

Enter the deflection distance from the normal position

Check the belt tension at least two times during the first 24 hours of operation

Any re-tensioning should fall between the minimum and maximum deflection force values

After adjusting, retighten the bolts holding the motor base to the channel

Sign off on the belt tension adjustment

Warning: Follow NFPA 72 requirements for smoke detector maintenance

Upload a photo of the cleaned smoke detector

Enter any issues found during the maintenance

Sign off on the smoke detector maintenance

After installation has been completed

1. Check the electrical supply voltage being supplied

Be sure that it is the same as listed on the unit nameplate

2. Set the room thermostat to the off position

3. Turn unit electrical power on

4. Set the room thermostat fan switch to on

5. Check indoor blower rotation