York Single Package Cooling Unit ZE036H12B2A1ABA1A1

Loosen six nuts (top and bottom) A

Ensure nuts (C) are not loosened

Measure deflection distance using belt tension checker

Enter the deflection force applied

Re-tighten nuts (A) after adjusting

Record the first deflection force measurement

Check the number and size of filters needed for the unit

Verify that filters are installed ahead of evaporator coil

Inspect filters for dirt and debris

Replace filters if cleaning is not sufficient

Ensure panel latches are properly positioned to maintain an airtight seal

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

Blow out loose particles from the piping.

Have all gas lines external to the unit been purged of air?

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

Remove screws holding the manifold to the burner supports

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

Remove the gas piping closure panel

Disconnect wiring to the gas valves and spark ignitors

Remove the manifold-burner gas valve assembly by lifting up and pulling back

Reverse the procedure to replace the assemblies ensuring burners are level and seated at the rear of the heat exchanger