Greenheck-fan VSU Make-Up Air Unit with Direct-Fired Gas Heater Manual de usuario Pagina 1

1Model VSU Make-Up Air UnitInstallation, Operation and Maintenance ManualPlease read and save these instructions. Read carefully before attempting to

10Model VSU Make-Up Air®Installation of Electrical WiringIMPORTANTBefore connecting power to the unit, read and understand the following instructions

11Model VSU Make-Up Air®Installation of Direct Gas PipingDetermine the Supply Gas RequirementsThe unit’s direct gas nameplate states the requirements

12Model VSU Make-Up Air®Vent Line SolenoidTo BurnerVent LineTo OutdoorsFrom SupplySafetyShut-off ValvesOptional Vent LineWARNINGNEVER test for a gas l

13Model VSU Make-Up Air®Unit Model Number _______________________________ (e.g. VSU-H20)Unit Serial Number _______________________________ (e.g. 1

14Model VSU Make-Up Air®NOTEThe most accurate way to measure the air volume is by using a pitot traverse method downstream of the blower. Other method

15Model VSU Make-Up Air®Set-Up Optional ComponentsAdjust the settings on the optional components. See the unit’s specific wiring diagram located on the

16Model VSU Make-Up Air®IMPORTANTProper air velocity over the burner is critical on direct-fired gas units. If the air velocity is not within the unit

17Model VSU Make-Up Air®IMPORTANTSetting the maximum firing rate during mild weather conditions may cause the high limit to trip out during extreme co

18Model VSU Make-Up Air®IMPORTANTIf the flame signal is not above 1.25 VDC and steady, consult the troubleshooting section.Flame Signal Check - Pilot

19Model VSU Make-Up Air®Building Pressure Control — a variable frequency drive is controlled according to input from a pressure sensing device.Turn bo

2Model VSU Make-Up Air®Inspection and Maintenance during StorageWhile in storage, inspect fans once per month. Keep a record of inspection and mainten

20Model VSU Make-Up Air®Operation - Recirculating Units (optional)NOTEBlower Start-Up, as shown on page 14, should be performed before the blower is r

21Model VSU Make-Up Air®Direct Gas Burner Sequence - Pilot Ignition1. Supply Fan Contact Closed• Power passes to the supply fan and heat switch2. H

22Model VSU Make-Up Air®Blower Does Not OperateTroubleshootingProper supply power at main disconnectCheck main voltage.Reference: Start-Up - Blower,

23Model VSU Make-Up Air®Motor OverampsTroubleshootingAir volume too high?Adjust drives or increase external static pressure as needed.Reference: Star

24Model VSU Make-Up Air®Insufficient AirflowTroubleshootingDamper(s) not fully opened?Adjust damper linkage(s), or replace faulty actuator(s).Damper act

25Model VSU Make-Up Air®Excessive Noise or VibrationTroubleshootingSheaves aligned?Align sheaves.Reference: Maintenance - Routine, V-Belt Drives, pg.

26Model VSU Make-Up Air®Heater Does Not Operate (Pilot Ignition)Does not attempt to light (No visible spark)Troubleshooting24 VAC between terminals W1

27Model VSU Make-Up Air®Heater Does Not Operate (Pilot Ignition)Attempts to light, but no pilot (visible spark)TroubleshootingGas pressure between the

28Model VSU Make-Up Air®Heater Does Not Operate (Pilot Ignition)Visible pilotTroubleshootingFlame signal greater than 1.25 VDCMeasure the flame signalw

29Model VSU Make-Up Air®Heater Does Not Operate (Direct Spark)Does not attempt to light (No visible spark)Troubleshooting24 VAC between terminals W1 a

3Model VSU Make-Up Air®Table of ContentsGeneral Safety Information ...1Receiving, Handling and Storage ...2Product Over

30Model VSU Make-Up Air®Heater Does Not Operate (Direct Spark)Attempts to light, but no flame (Visible spark)TroubleshootingCheck inlet gas pressure.Re

31Model VSU Make-Up Air®Maintenance - RoutineCAUTIONLock-out the gas and the electrical power to the unit before performing any maintenance or service

32Model VSU Make-Up Air®BearingsThe bearings for the fans are carefully selected to match the maximum load and operating conditions of the specific cla

33Model VSU Make-Up Air®Burner DifferentialPressure SensorHigh Gas PressureSwitch (optional)Low Gas PressureSwitch (optional)Manual PilotShut-Off Valv

34Model VSU Make-Up Air®Typical Gas Train Layout with Direct Spark IgnitionThis is a typical gas train. The gas train in your unit may be different.Re

35Model VSU Make-Up Air®Control Center LayoutDirty Filter SwitchReference13 2226 28272015214178293516231718191425101211624 1. Supply Motor Starter —

36470654 • VSU, Rev. 2, April 2013 Copyright 2013 © Greenheck Fan CorporationGreenheck’s Model VSU catalog provides additional information describing

4Model VSU Make-Up Air®SubassembliesFilter Section / Vertical Mounting StandThe filter section of the unit is factory installed in the mounting stand a

5Model VSU Make-Up Air®Burner, Blower and Control Center SectionThe burner section, blower section and control center of the unit are all combined int

6Model VSU Make-Up Air®Burner SubassemblyThe burner subassembly consists of the gas train with its controls, valves, pressure regulator, burner(s), an

7Model VSU Make-Up Air®Burner/Blower SectionUse a crane and a spreader bar hooked to the factory lifting lugs (shown below) to lift and center the uni

8Model VSU Make-Up Air®Complete InstallationA typical horizontal discharge installation is shown. Gas and/or electrical lines can be connected at this

9Model VSU Make-Up Air® 5. Fasten three (3/8 in. x 1-1/2 in.) hex head bolts into the side of the platform base. Secure each bolt with two (3/8 in.)