York Single Package Air Conditioner ZJ102C24R4B5EAA1A1

Verify that the unit is properly phased at the factory.

Is the blower rotating in the correct direction?

Is the compressor rotating in the correct direction?

Measure the amperage of the scroll compressor.

Are the suction and discharge pressures similar?

Is the scroll compressor producing a high noise level?

Ensure main manual shut-off valve is closed and all power to the unit is shut off

Open the union fitting just upstream of the unit gas valve and downstream from the main manual shut-off valve in the gas supply line

Remove the screws holding each end of the manifold to the manifold supports

Disconnect wiring to the gas valves and spark igniters

Remove the manifold & gas valve assembly

Inspect and/or replace orifices

Remove the heat shield on top of the manifold supports to access burners

Ensure burners are level and seated at the rear of the gas orifice

Check that all filters are in place and clean

Are the filters clean and in good condition?

Clean or replace filters if necessary

Ensure filters are installed ahead of evaporator coil

Are the filters properly installed?

Is the unit operating with filters properly installed?

Connect a manometer to the outlet pressure port on the gas valve

Remove plastic cap covering HI and LO pressure adjustment screws

Second Stage Pressure Adjustment

Set thermostat to call for second stage heat and start furnace

Adjust second stage (HI) manifold pressure using a screwdriver

Enter the second stage manifold pressure reading

Use special pipe dope for assembly

Clean piping of dirt and scale by hammering on the outside of the pipe

Blow out loose particles from the pipe

Ensure all gas lines external to the unit have been purged of air