Bryant 310JAV, 310AAV warranty Start-Up Procedures, Adjustments

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Personal injury can result form sharp metal edges, etc. Be careful when removing parts. Gloves and safety glasses should be worn when servicing equipment.

1.Maintain 115-v wiring and ground. Improper polarity will result in rapid flashing LED and no furnace operation.

2.Make thermostat wire connections at the 24-v terminal block on the furance control. Failure to make proper connections will result in improper operation. (See Fig. 24.)

3.Gas supply pressure to the furnace must be greater than 4.5-in. wc (0.16 psig) but not exceed 14-in. wc (0.5 psig).

4.Check all manual-reset switches for continuity.

5.Install blower compartment door. Door must be in place to operate furnace.

6.Replace outer door.

Step 2—Start-Up Procedures

Never purge a gas line into a combustion chamber. Never use matches, candles, flame, or other sources of ignition for the purpose of checking leakage. Use a soap-and-water solution to check for leakage. Failure to follow this warning can cause fire, explosion, personal injury, or death.

1.Purge gas lines after all connections have been made.

2.Check gas lines for leaks.

Blower access door switch opens 115-v power to control. No component operation can occur unless switch is closed. Caution must be taken when manually closing this switch for service purposes. Failure to follow this warning could result in electrical shock, personal injury, or death.

3.To Begin Component Self-Test: Disconnect the thermostat R lead from furnace control board. Manually close the blower door switch. Briefly short the TEST/TWIN terminal to the COM 24V terminal until LED goes out. Remove jumper from terminals. (See Fig. 23.)

NOTE: The furnace control allows all components, except the gas valve, to be run for short period of time. This feature helps diagnose a system problem in case of a component failure. Component test feature will not operate if any thermostat signal is present at the control.

Component test sequence is as follows:

Refer to service label attached to furnace or see Fig. 43.

a.LED will display previous status code 4 times.

b.Inducer motor starts and continues to run until Step f of component test sequence.

c.Hot surface ignitor is energized for 15 sec., then off.

d.Blower motor operates on HEAT speed for 10 sec.

e.Blower motor operates on COOL speed for 10 sec.

f.Inducer motor stops.

g.Reconnect R lead to furnace control board, release blower door switch and re-install blower door.

4.Operate furnace per instruction on door.

5.Verify furnace shut down by lowering thermostat setting below room temperature.

6.Verify furnace restarts by raising thermostat setting above room temperature.

Step 3—Adjustments

DO NOT bottom out gas valve regulator adjusting screw. This can result in unregulated manifold pressure and result in excess overfire and heat exchanger failures.

DO NOT redrill orifices. Improper drilling (burrs, out-of- round holes, etc.) can cause excessive burner noise and misdirection of burner flames. This can result in flame impingement of heat exchangers, causing failures. (See Fig. 41.)

Furnace gas input rate on rating plate is for installations at altitudes up to 2000 ft. Furnace input rate must be within ±2 percent of furnace rating plate input.

In the U.S.A., the input rating for altitudes above 2,000 ft. must be reduced by 4 percent for each 1,000 ft. above sea level. In Canada, input rating must be reduced by 10 percent for altitudes of 2,000 ft. to 4,500 ft. above sea level.

1.Determine the correct gas input rate. In the U.S.:

For installations below 2000 ft., refer to the unit rating plate. For installations above 2000 ft., multiply the input on the rating plate by the de-rate multiplier in Table 6 for the correct input rate.

In Canada:

At installation altitudes from 2000 to 4500 ft, this furnace must be derated 10 percent by an authorized Gas Conversion Station or Dealer. To determine correct input rate for altitude, see example 1 and use 0.90 as derate multiplier factor.

EXAMPLE 1:

88,000 BTUH INPUT FURNACE INSTALLED AT 4300 FT.

		Derate		Furnace Input Rate
Furnace Input Rate	X	Multiplier	=	at Installation
at Sea Level		Factor		Altitude
88,000	X	0.90	=	79,200

2.Determine the correct orifice and manifold pressure adjust- ment. There are two different orifice and manifold adjustment tables.

All models in all positions, except Low NOx models in downflow or horizontal positions, use Table 10 (22,000 BTUH/Burner)

Low NOx models in the downflow or horizontal positions must use Table 11 (21,000BTUH/Burner). See input listed on furnace rating plate.

a.Obtain average yearly gas heat value (at installed altitude) from local gas supplier.

b.Obtain average yearly gas specific gravity from local gas supplier.

c.Find installation altitude in Table 10 or 11.

d.Find closest natural gas heat value and specific gravity in Table 10 or 11.

e.Follow heat value and specific gravity lines to point of intersection to find orifice size and manifold pressure settings for proper operation.

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