York Predator Z series Installation Instructions Manual

Contents

5370596-YIM-C-051842 Johnson Controls Ducted SystemsNOTE: De-energize the compressors before taking any testmeasurements to assure a dry evaporator coil.4. The CFM through the unit can be determined from thepressure drop indicated by the manometer by referring toFigure 28. In order to obtain an accurate measurement, becertain that the air filters are clean.5. To adjust Measured CFM to Required CFM, see SUPPLYAIR DRIVE ADJUSTMENT.6. After readings have been obtained, remove the tubes andreplace the dot plugs.7. Tighten blower pulley and motor sheave set screws afterany adjustments. Re-check set screws after 10-12 hrs. runtime is recommended.Method Two1. Drill two 5/16 inch holes, one in the return air duct as closeto the inlet of the unit as possible, and another in the supplyair duct as close to the outlet of the unit as possible.2. Using the whole drilled in step 1, insert eight inches of 1/4inch metal tubing into the airflow of the return and supplyair ducts of the unit.NOTE: The tubes must be inserted and held in positionperpendicular to the airflow so that velocity pressurewill not affect the static pressure readings.3. Use an Inclined Manometer or Magnehelic to determinethe pressure drop across the unit. This is the ExternalStatic Pressure (ESP). In order to obtain an accuratemeasurement, be certain that the air filters are clean.4. Determine the number of turns the variable motor sheaveis open.5. Select the correct blower performance table for the unitfrom Tables 17 and 18. Tables are presented for side anddownflow configuration.6. Determine the unit Measured CFM from the BlowerPerformance Table, External Static Pressure and thenumber of turns the variable motor sheave is open.7. To adjust Measured CFM to Required CFM, see SUPPLYAIR DRIVE ADJUSTMENT.8. After reading has been obtained, remove the tubes andseal holes.9. Tighten blower pulley and motor sheave set screws afterany adjustments. Re-check set screws after 10-12 hrs. runtime is recommended.NOTE: With the addition of field installed accessories repeatthis procedure.Figure 28: Dry Coil Delta PFailure to properly adjust the total system air quantitycan result in extensive blower damage.Failure to properly adjust the total system air quantitycan result in extensive blower damage.8501050125014501650185020502250245026500 0.02 0.04 0.06 0.08 0.1 0.12Air Flow (CFM)Dry Coil Delta P (IWG)037049, 061