York Single Package Air Conditioner ZF120N24R5B1BAA1A1

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

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

Loosen six nuts (top and bottom) A

Ensure nuts (C) are not loosened

Use belt tension checker to apply perpendicular force and obtain 4mm deflection distance

Record the deflection force applied

Re-tighten nuts (A) after adjustment

Enter the number of times belt tension was checked in the first 24 hours

Verify that the ZF120-150 unit is properly phased at the factory.

Is the compressor rotating in the correct direction?

Is the scroll compressor drawing normal amperage?

Are the suction and discharge pressures normal?

Is the noise level of the scroll compressor normal?

Is the electrical connection to the unit correctly phased?

Check that all filters are installed ahead of the evaporator coil

Inspect filters for dirt and debris

Clean or replace dirty filters with the same size and type

Ensure the unit is not operated without filters properly installed

Verify panel latches are properly positioned to maintain an airtight seal

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