Bryant 580F installation instructions Ix. Cooling, To Shut Off Unit, X. Main Burners, Xi. Heating

The suction and discharge pressure levels should now move to their normal start-up levels.

NOTE: When the compressor is rotating in the wrong direc- tion, the unit makes an elevated level of noise and does not provide cooling.

IX. COOLING

Set space thermostat to OFF position. To start unit, turn on main power supply. Set system selector switch at COOL posi- tion and fan switch at AUTO. position. Adjust thermostat to a setting below room temperature. Compressor, outdoor fan and evaporator motor start on closure of contactor.

Check unit charge. Refer to Service, Refrigerant Charge sec- tion, page 48.

Reset thermostat at a position above room temperature. Compressor will shut off. Evaporator fan will shut off after 30-second delay.

To Shut Off Unit

Set system selector switch at OFF position. Resetting ther- mostat at a position above room temperature shuts unit off temporarily until space temperature exceeds thermostat setting.

X. MAIN BURNERS

Main burners are factory set and should require no adjustment.

TO CHECK ignition of main burners and heating controls, move thermostat set point above room temperature and ver- ify that the burners light and evaporator fan is energized. After ensuring that the unit continues to heat the building, lower the thermostat setting below room temperature and verify that the burners and evaporator fan turn off. (Fan will turn off only if fan selector switch is in the AUTO. position.)

Refer to Table 34A and 34B for the correct orifice to use at high altitudes.

XI. HEATING

1.Purge gas supply line of air by opening union ahead of gas valve. If gas odor is detected, tighten union and wait 5 minutes before proceeding.

2.Turn on electrical supply and manual gas valve.

3.Set system switch selector at HEAT position and fan switch at AUTO. or ON position. Set heating temper- ature lever above room temperature.

4.The induced-draft motor will start.

5.After a call for heating, the main burners should light within 5 seconds. If the burner does not light, then there is a 22-second delay before another 5-second try. If the burner still does not light, the time delay is repeated. If the burner does not light within 15 min- utes, there is a lockout. To reset the control, break the 24-v power to W1.

6.The evaporator-fan motor will turn on 45 seconds af- ter the burners are ignited.

7.The evaporator-fan motor will turn off 45 seconds af- ter thermostat temperature is satisfied.

8.Adjust airflow to obtain a temperature rise within the range specified on the unit nameplate.

NOTE: The default value for the evaporator-fan motor ON/ OFF delay is 45 seconds. The Integrated Gas Unit Controller (IGC) modifies this value when abnormal limit switch cycles occur. Based upon unit operating conditions, the ON delay can be reduced to 0 seconds and the OFF delay can be extended

to 180 seconds. When one flash of the LED is observed, the evaporator-fan ON/OFF delay has been modified.

If the limit switch trips at the start of the heating cycle dur- ing the evaporator ON delay, the time period of the ON delay for the next cycle will be 5 seconds less than the time at which the switch tripped. (Example: If the limit switch trips at 30 seconds, the evaporator-fan ON delay for the next cycle will occur at 25 seconds.) To prevent short-cycling, a 5-second reduction will only occur if a minimum of 10 minutes has elapsed since the last call for heating.

The evaporator-fan OFF delay can also be modified. Once the call for heating has ended, there is a 10-minute period dur- ing which the modification can occur. If the limit switch trips during this period, the evaporator-fan OFF delay will increase by 15 seconds. A maximum of 9 trips can occur, extending the evaporator-fan OFF delay to 180 seconds.

To restore the original default value, reset the power to the unit.

To Shut Off Unit

Set system selector switch at OFF position. Resetting heat- ing selector lever below room temperature will temporarily shut unit off until space temperature falls below thermostat setting.

Table 34A — Altitude Compensation* — Standard Units

	74,000 AND 115,000 BTUH		150,000 BTUH
ELEVATION	NOMINAL INPUT		NOMINAL INPUT
	Natural	Liquid	Natural	Liquid
(ft)	Gas	Propane	Gas	Propane
	Orifice	Orifice	Orifice	Orifice
	Size†	Size†	Size†	Size†
0-2,000	33	43	30	37
2,000	36	44	31	39
3,000	36	45	31	40
4,000	37	45	32	41
5,000	38	46	32	42
6,000	40	47	34	43
7,000	41	48	35	43
8,000	42	49	36	44
9,000	43	50	37	45
10,000	44	50	39	46
11,000	45	51	41	47
12,000	46	52	42	48
13,000	47	52	43	49
14,000	48	53	44	50

*As the height above sea level increases, there is less oxygen per cubic foot of air. Therefore, heat input rate should be reduced at higher altitudes.

†Orifices available through your Bryant distributor.

Table 34B — Altitude Compensation* — Low NOx Units

	60,000 AND 90,000 BTUH		120,000 BTUH
ELEVATION	NOMINAL INPUT		NOMINAL INPUT
	Natural	Liquid	Natural	Liquid
(ft)	Gas	Propane	Gas	Propane
	Orifice	Orifice	Orifice	Orifice
	Size†	Size†	Size	Size†
0-2,000	38	45	32	42
2,000	40	47	33	43
3,000	41	48	35	43
4,000	42	49	36	44
5,000	43	49	37	45
6,000	43	50	38	45
7,000	44	50	39	46
8,000	45	51	41	47
9,000	46	52	42	48
10,000	47	52	43	49
11,000	48	53	44	50
12,000	49	53	44	51
13,000	50	54	46	52
14,000	51	54	47	52

*As the height above sea level increases, there is less oxygen per cubic foot of air. Therefore, the input rate should be reduced at higher altitudes.

†Orifices are available through your local Bryant distributor.

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