Greenheck Fan PVE-35, PVE-55 manual Parts List Sequence of Operation, Basic Unit, Summer Operation

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Parts List

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Sequence of Operation

Basic Unit

The PVe units are prewired such that when a call for outside air is made (via field supplied 24 VAC control signal wired to unit control center), the supply and exhaust fan are energized and optional motorized dampers open. The PVe is normally slaved (24 volt) to the roof top air handler. When the roof top air handler starts, the auxiliary contactor in the air handler closes to start the PVe.

Summer Operation

1. Supply blower

2

Outdoor air is preconditioned (temperature is decreased) by the transfer of energy from the cooler, drier, exhaust air via the aluminum heat exchanger. The preconditioned air is typically mixed with return air going back to the air handler for final conditioning.

• Forward curved fan

• Adjustable motor mount for belt tensioning

• Adjustable sheaves for speed control

2. Vibration isolators (quantity 4 per blower)

• Neoprene

3. Aluminum plate heat exchanger

4. Supply weatherhood with 2-inch aluminum mesh filter

5. Exhaust weatherhood with birdscreen

6. Supply and exhaust air filter racks for

2-inch pleated, 30% efficient filters

7.Electrical control box (standard features)

Single point power

Disconnect interlocked with access door

Motor starters for the supply and exhaust blower

24 VAC, control circuit with terminal strip Not depicted on this image

8.Exhaust blower

Forward curved fan

Adjustable motor mount for belt tensioning

Adjustable sheaves for speed control

Economizer Operation: Refer to Economizer Application/Operation section.

Winter Operation

Outdoor air is preconditioned (temperature is increased) by the transfer of energy from the warmer, more humid exhaust air via the aluminum heat exchanger. The preconditioned air is typically mixed with return air going back to the air handler for final conditioning.

Frost Control Operation: Refer to Frost Control Application/Operation section.

Other Accessories:

Dirty Filter Sensor: Refer to Optional Accessories section

CO2 Sensor: Refer to Optional Accessories section

VFD on Blowers: VFDs on blowers are often used as part of a demand control ventilation system. This type of system takes advantage of varying occupancy through the use of CO2 sensors to monitor space CO2 levels. If CO2 levels are low in the space, the VFD will operate the blowers at minimum airflow required by code. As the space occupancy increases and CO2 levels increase, the VFD will increase the amount

of fresh outdoor air being brought in to offset the CO2 levels in the space (exhaust airflow is increased proportionally as outdoor airflow increases). As CO2 levels come back down, the airflow will decrease back to minimum requirements.

Model PVe Heat Recovery Unit 25

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Contents Models PVe-20 PVe-35 PVe-45 PVe-55 General Safety InformationReceiving Inspection and Maintenance during StorageUnpacking HandlingSupplemental Installation Operation and Maintenance Manuals Table of ContentsInstallation Basic OperationLifting Installation StagesLifting with a Crane Lifting with a ForkliftRoof Curb and Rail Mounting Service ClearancesRoof Curb Mounting Curb Dimensions and WeightsDuctwork Connections Rail Mounting / Layout Access Panel Description and LocationDrain Trap Dimensional DataElectrical Information Electric Heater Application/Operation Typical Control Center ComponentsFrost Control Application/Operation Optional AccessoriesEconomizer Application/Operation Timed Exhaust frost controlFactory Set Points Variable Frequency Drives for Energy Recovery BlowersDrive Operation Modulating Control for FAN Speed Typical Wiring Diagram Dirty Filter Sensor Service OutletCO2 Sensor Vapor Tight LightsIndicator Lights powered by the ER Unit Remote Control Panel and Wiring SchematicsDay Timer or On/Off Switch Hand/Off/Auto SwitchDrawing Terminal Strip Labels Sensors Mounted by FactoryStart-Up Checklist Pre Start-Up Checklist check as items areStart-Up General Start-Up InformationOptional Accessories section Optional Accessories ChecklistEconomizer Application / Operation section Variable Frequency Drives sectionUnit Start-Up Vibration Maintenance Overview Lubrication Routine MaintenanceDampers Fan BeltsInternal Filter Maintenance External Filter MaintenanceDoor Seal Maintenance Fan Wheel & FastenersOther Accessories Parts List Sequence of OperationBasic Unit Summer OperationTest and Balance Report Troubleshooting AirflowDesign Airflow Measured AirflowSymptom Possible Cause Corrective Action Troubleshooting UnitTroubleshooting Unit Maintenance Log Maintenance Log Maintenance Log Warranty