Bryant 580F Perfect Humidity System Charging, IX. GAS Valve Adjustment, Natural Gas, Main Burners

NOTE: Dimensions are in inches.

Fig. 40 — Condenser Fan Adjustment, 580F180, 210, 300

NOTE: Dimensions are in inches.

Fig. 41 — Condenser Fan Adjustment, 580F240

								BOTH CIRCUITS
				ALL OUTDOOR FANS MUST BE OPERATING
(DEG F)	140
VALVE	120
			ADD		CHARGE		IF ABOVE CURVE
LIQUIDAT	100
TEMPERATURELIQUID
	80
	60								REDUCE CHARGE IF BELOW CURVE
	40
		100				150	200			250	300	350	400
	50

LIQUID PRESSURE AT LIQUID VALVE (PSIG)

Fig. 42 — Cooling Charging Chart

C. To Use the Cooling Charging Chart

Use the above temperature and pressure readings, and find the intersection point on the cooling charging chart. If inter- section point on chart is above line, add refrigerant. If inter- section point on chart is below line, carefully recover some of the charge. Recheck suction pressure as charge is adjusted.

NOTE: Indoor-air cfm must be within normal operating range of unit. All outdoor fans must be operating.

The TXV (thermostatic expansion valve) is set to maintain between 15 and 20 degrees of superheat at the compressors. The valves are factory set and should not require re-adjustment.

D. Perfect Humidity™ System Charging

The system charge for units with the Perfect Humidity option is greater than that of the standard unit alone. The charge for units with this option is indicated on the unit nameplate drawing. To charge systems using the Perfect Humidity dehumidification package, fully evacuate, recover, and re-charge the system to the nameplate specified charge level. To check or adjust refrigerant charge on systems using the Perfect Humidity dehumidification package, charge per the standard subcooling charts. The subcooler MUST be deenergized to use the charging charts. The charts reference a liquid pressure (psig) and temperature at a point between the condenser coil and the subcooler coil. A tap is provided on the unit to measure liquid pressure entering the sub- cooler (leaving the condenser).

IX. GAS VALVE ADJUSTMENT

A. Natural Gas

The gas valve opens and closes in response to the thermostat or limit control.

When power is supplied to valve terminals D1 and C2, the main valve opens to its preset position.

The regular factory setting is stamped on the valve body (3.3 in. wg).

To adjust regulator:

1.Set thermostat at setting for no call for heat.

2.Turn main gas valve to OFF position.

3.Remove 1/8-in. pipe plug from manifold or gas valve pressure tap connection. Install a suitable pressure- measuring device.

4.Set main gas valve to ON position.

5.Set thermostat at setting to call for heat.

6.Remove screw cap covering regulator adjustment screw (see Fig. 43).

7.Turn adjustment screw clockwise to increase pres- sure or counterclockwise to decrease pressure.

8.Once desired pressure is established, set thermostat setting for no call for heat, turn off main gas valve, remove pressure-measuring device, and replace 1/8-in. pipe plug and screw cap.

X.MAIN BURNERS

For all applications, main burners are factory set and should require no adjustment.

A.Main Burner Removal

1.Shut off (field-supplied) manual main gas valve.

2.Shut off power to unit.

3.Remove unit control box access panel, burner section access panel, and center post (Fig. 4-6).

4.Disconnect gas piping from gas valve inlet.

5.Remove wires from gas valve.

6.Remove wires from rollout switch.

7.Remove sensor wire and ignitor cable from IGC board.

8.Remove 2 screws securing manifold bracket to basepan.

9.Remove 2 screws that hold the burner support plate flange to the vestibule plate.

10.Lift burner assembly out of unit.

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