Bryant 355CAV Start-Up,Adjustment And Safety Check, General, Select Setup Switch Positions

2.Locate heat tape between sides of condensate trap back. (See Fig. 46.)

3.Use wire ties to secure heat tape in place. Wire ties can be positioned in notches of condensate trap sides. (See Fig. 46.)

4.Wrap field drain pipe with remaining heat tape, approximately 1 wrap per ft.

5.When using field-supplied heat tape, follow heat tape manufacturer’s instructions for all other installation guidelines.

START-UP, ADJUSTMENT AND SAFETY

CHECK

Step 1 — General

1.Furnace must have a 115-v power supply properly connected and grounded.

NOTE: Proper polarity must be maintained for 115-v wiring. If polarity is incorrect, control status indicator light flashes rapidly and furnace does not operate.

2.Thermostat wire connections at terminals R, W/W1, G, and Y/Y2 must be made at 24-v terminal block on furnace control.

3.Natural gas service pressure must not exceed 0.5 psig (14- in. wc), but must be no less than 0.16 psig (4.5-in. wc).

4.Blower access panel must be in place to complete 115-v electrical circuit to furnace.

!CAUTION

UNIT MAY NOT OPERATE

Failure to follow this caution may result in intermittent unit operation or performance satisfaction.

These furnaces are equipped with a manual reset limit switch in burner box. This switch opens and shuts off power to the gas valve if an overheat condition (flame rollout) occurs in burner enclosure. Correct inadequate combustion-air supply or improper venting condition before resetting switch. DO NOT jumper this switch.

Before operating furnace, check flame rollout manual reset switch for continuity. If necessary, press button to reset switch.

Step 2 — Select Setup Switch Positions

Air Conditioning (A/C) Setup Switches

The air conditioning setup switches are used to match furnace airflow to cooling unit used.

To set the desired cooling airflow:

1.Remove main furnace door and blower access panel.

2.Locate A/C setup switches on furnace control. (See Fig. 33.)

3.Determine air conditioning tonnage used.

4.Use Fig. 47 or wiring schematic to determine proper setup position of A/C switches. (See Fig. 48 and Fig. 49.)

NOTE: Excessive airflow caused by improper A/C switch setup may cause condensate blowoff in cooling mode.

5. Replace main furnace door and blower access panel.

NOTE: EAC-1 terminal is energized whenever blower operates. HUM terminal is only energized when blower is energized in heating.

Continuous Fan (CF) Setup Switches

The CF setup switches are used to select desired airflow when thermostat is in continuous fan mode or to select low-cooling airflow for two-speed cooling units. This setup feature allows

continuous fan airflow or low-cooling airflow to be adjusted. To set desired continuous fan airflow or low-cooling airflow:

1.Remove main furnace door and blower access panel.

2.Locate CF setup switches on furnace control. (See Fig. 33.)

3.Determine desired continuous fan airflow or low-cooling airflow.

4.Use Fig. 47 or wiring schematic to determine proper setup position of CF switches. (See Fig. 48 and Fig. 49.)

5.Replace main furnace door and blower access panel.

AIR CONDITIONING (A/C) OR CONTINUOUS-FAN (CF)

AIRFLOW SELECTION CHART

BASED ON 350 CFM/TON (SETUP SWITCH SW1-5 OFF)

SETUP SWITCH SW3 POSITIONS

MODEL

SIZE

060, 3.5T080	DEF.	525 2		700	875	1050 1	1225	1225	1225
5T080, 100	DEF.	700 2		875	1050	1225	1400	1750 1	1750
120	DEF.	700		875 2	1050	1225	1400	1750 1	2100
BASED ON 400 CFM/TON (SETUP SWITCH SW1-5 ON)
MODEL			SETUP SWITCH SW3 POSITIONS
SIZE
060, 3.5T080	DEF.	600 2		800	1000	1200 1	1400	1400	1400
5T080, 100	DEF.	800 2		1000	1200	1400	1600	2000 1	2000
120	DEF.	800		1000 2	1200	1400	1600	2000 1	2100

1.DEFAULT A/C AIRFLOW WHEN A/C SWITCHES ARE IN OFF POSITION

2.DEFAULT CONT. FAN AIRFLOW WHEN CF SWITCHES ARE IN OFF POSITION

3.SWITCH POSITIONS ARE ALSO SHOWN ON FURNACE WIRING DIAGRAM

A07424

Fig. 47 - A/C or CF Airflow Selection Chart Based on 350

and 400 CFM/Ton

Setup Switches (SW1)

The furnace control has 8 setup switches that may be set to meet the application requirements. To set these setup switches for the appropriate requirement:

1.Remove main furnace door and blower access panel.

2.Locate setup switches on furnace control. (See Fig. 33.)

3.See Table 9 for setup switch description. (See Fig. 48 and Fig. 49.)

4.Replace main furnace door and blower access panel.

NOTE: If a bypass humidifier is used, setup switch SW1-3 (Low Heat Rise Adjust) should be in ON position. This compensates for the increased temperature in return air resulting from bypass.

NOTE: If modulating dampers are used, blower motor automatically compensates for modulating dampers.

Additional Setup Switches (SW4)

The furnace control has 3 additional setup switches labeled SW4. (See Fig. 33.) Setup switch SW4-2 can be used to lock the furnace into medium heat. When setup switch SW4-2 is ON the furnace will remain at medium heat until W/W1 is de-energized to end a heating cycle or when both W/W1 and W2 are energized. When both W/W1 and W2 are energized the furnace will run at high heat. The other 2 setup switches are currently not used for anything. When setup switch SW4-2 is ON it will over ride setup switch SW1-2 if it is ON. To activate setup switch SW4-2:

1. Remove main furnace door and blower access panel.

355CAV

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