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Set-Up Optional Components
Adjust the settings on the optional components. See the unit’s specific wiring diagram located on the access door or the unit.
•Heating Inlet Air Sensor
Typical setting:
•Building Freeze Protection
Typical setting: 5 minutes; 45ºF
•Dirty Filter Gauge
Typical setting: Settings vary greatly for each unit. (see Reference section for adjusting information)
Start-Up - Direct Gas
important
For proper unit function and safety, follow the
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This
Check the Supply Gas Pressure
Check the supply gas pressure and compare it with the unit’s nameplate pressure requirements. Adjust the supply regulator as needed until the supply gas pressure is within the specified range. The direct gas nameplate is located on the outside of the unit on the control center side.
Minimum and maximum gas pressures for maximum output
MAX BTU/HR
BTU/H MAX
NORMAL MANIFOLD
PRESSURE“ WC PRESSION DÕADMISSION
NORMALE
MIN GAS
PRESSURE“ WC PRESSION DE GAZ
MIN BURNER
PRESSURE DROP“ WC PERTE MIN DE PRESSION
DANS LE BRULEUR
TYPE OF GAS
NATURE DU GAZ
EQUIPPED FOR | AGAINST |
| SCFM |
CONCU POUR | CONTE |
MIN BTU/HR
BTU/H MIN
MIN GAS PRESSURE
FOR MAX OUTPUT“ WC PRESSION DE GAZ MIN
POUR PUISSANCE MAX
MAX GAS
PRESSURE“ WC PRESSION DE GAZ
MAX
MAX BURNER
PRESSURE DROPPSI PERTE MAX DE PRESSION
DANS LE BRULEUR
DESIGN ∆T | F | |
∆T NORMALE | ||
| ||
|
| |
| EXTERNAL STATIC PRESSURE | |
| “ WC | |
| PRESSION STATIQUE EXTERIEURE |
Type of gas
Direct Gas Nameplate
Check the Pilot Gas Pressure
Check the pilot gas pressure. The recommended gas pressure is 3 in. wg. Adjust the pilot regulator as needed. See the Gas Train Layout in the Reference section for the location of the pilot pressure test port and pilot regulator.
Check the Optional High and Low Gas Pressure Switches
Check the settings on the high and low gas pressure switches. The high gas setting is typically 8 in. wg (2 kPa) and the low gas setting is typically 3 in. wg (0.7 kPa). The switches are set at the factory and should not need adjustment. Adjust the settings if needed. See the Gas Train Layout in the Reference section for the high and low pressure switch location.
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The purpose of the high and low gas pressure switches is to automatically shut down the burner if the inlet gas pressure is too low for the burner to safely light, or if the manifold pressure is too high for the burner to operate properly.
Model VSU
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