Greenheck Fan MSCF-BI, MSCF-FC manual Sequence of Operation Electric Heater

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Sequence of Operation - Electric Heater

1.Electric heaters are divided in to equally sized steps. For example, a 60 kW heater with 3 steps will have 20 kW per step. The thermostat and step controller will control these steps.

2.120 Volt power from the control center (when supplied) or by others with out a control center, is delivered to the electric heater for the step controller. This power must be interlocked with the supply fan, so when the fan is off, the heater control power is off.

3.A step control with the thermostat set to 70ºF the heater will be off with a temperature sensing above 70ºF. As the temperature varies the steps turn on and off to hold the setpoint discharge temperature. The colder the discharge temperature becomes the more steps the controller will energize.

4.With a step controller, in addition to the fan interlock mentioned in Step 2, the heater has an airflow switch to prove that airflow is established before energizing the steps. The heater also has an automatic resetting highlimit switch and manual resetting highlimit switch set above the automatic switch to protect from overheating.

5.For more detailed information on your specific controller, please review the controller spec sheet supplied with the heater.

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Model MSCF Modular Small Cabinet Fan 15

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Contents General Safety Information Installation, Operation and Maintenance ManualUnpacking Inspection and Maintenance during StorageService Clearance ReceivingUnit Layout Table of ContentsMounting Instructions Hanging InstructionsExternal Mounting Isolation Mscf Mounting Dimensions Modular ConstructionHorizontal Hanging Dimensional Data WeightsFilter Sizes and Quantity Coil Dimensions Airflow From the center connection Inlet and exits from First suction header on the entering air sideCoil is circuited to the top distributor. With Airflow from left to right, the fluid enters the coilSystem Start-Up Symptom Possible Cause Corrective Action TroubleshootingDirect Expansion DX Coils Start-Up of Coil ModuleHot Water and Chilled Water Steam CoilsFreezing Conditions entering air below 35F Drain Pan / Drain TrapTraps ControlsCalculation of Line Currents amps Installation of Electric Heater optionalElectrical Wiring Instructions Sizing of Supply ConductorsSequence of Operation Electric Heater Yearly Fan MaintenanceTwo Weeks after Start-Up Every Three 3 MonthsCoil Maintenance Drain Pan MaintenanceStart-Up Documentation Maintenance Log Maintenance Log Warranty