Carrier 48PG16 Check Unit Operation and Make Necessary Adjustments, Panel and Filter Locations

ECONOMIZER HOODS

CONDENSER COIL ACCESS

PANEL

OUTDOOR AIR SCREENS (HIDDEN)

BAROMETRIC		FILTER	GAS SECTION
RELIEF DAMPER
		ACCESS DOOR	ACCESS DOOR
HOODS
ELECTRICAL	BASEPAN	CONTROL BOX
	CONNECTIONS
OPTIONS		AND COMPRESSOR
	ACCESS PANEL
PANEL		ACCESS DOOR

Fig. 1 — Panel and Filter Locations

INDUCED

DRAFT

MOTOR

MAIN GAS

VALVE

HEAT	COMBUSTION	MAIN
EXCHANGER	FAN HOUSING	BURNER
SECTION		SECTION

Fig. 2 — Typical Gas Heating Section

Step 4 — Check Unit Operation and Make Necessary Adjustments

NOTE: Gas pressure must not be less than 5 in. wg or greater than 13 in. wg at the unit connection.

1.Remove pressure tap plug from manifold pipe and connect a pressure gage or manometer.

2.Turn on electrical supply.

3.Open the manual shutoff valve on the gas supply pip- ing. Check pipe connection to main gas valve for leaks.

4.Set the switch on the main gas valve to the ON position.

5.Call for high stage heat (W2 energized). The unit may require several ignition attempts due to trapped air in the manifold pipe.

6.When main burners ignite check orifice fittings for leaks. Repair if necessary.

Never use a match or other open flame to check for leaks. Use a soap and water solution. Fire or serious injury could result.

If unit is equipped with a 2-stage gas valve, ensure valve has energized second stage (high fire) before adjusting manifold pressure. Improper manifold pressures may cause explosion or injury.

7.Verify that manifold pressure is between 2.7 and 3.0 in. wg while in high fire (W2 energized). Readjust pressure if necessary.

This unit is designed to operate at 3.0 in. wg (± 0.3 in. wg) manifold pressure at high fire. Exceeding this pressure will cause explosion or injury.

8.Shut down unit by turning down thermostat (units with electro-mechanical control) or putting unit in Service Test mode (units with ComfortLink™ control), shut- ting off manual gas valve, and shutting down power to unit.

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