Bryant 577D----A 577D-- --A, Symptom, Cause, Remedy, Burners will not ignite, Inadequate heating

Table 10 – Troubleshooting Chart - Gas Furnace Operation

SYMPTOM		CAUSE		REMEDY
	Water in gas line		Drain. Install drip leg.
	No power to unit		Check power supply fuses, wiring or circuit
			breaker.
			Check transformer.
	No 24--v power supply to control circuit		NOTE: Some transformers have internal over--
			current protection that requires a cool--down peri-
			od to reset.
Burners will not ignite	Mis--wired or loose connections		Check all wiring and wire nut connections
			Check flame ignition and sense electrode posi-
	Misaligned spark electrodes		tioning.
			Adjust as necessary.
			1. Check gas line for air. Purge as necessary.
			NOTE: After purging gas line of air, wait at least 5
	No gas at main burners		minutes for any gas to dissipate before attempt-
			ing to light unit.
			2. Check gas valve.
	Inducer pressure switch not closing		1. Check pressure switch wires, connections,
			and tubing. Repair or replace if necessary.
	Dirty air filter		Clean or replace filter as necessary
	Gas input to unit too low		Check gas pressure at manifold match with that
			on unit nameplate
Inadequate heating
	Unit undersized for application		Replace with proper unit or add additional unit
	Restricted airflow		Clean or replace filter. Remove any restriction.
	Limit switch cycles main burners		Check rotation of blower, temperature rise of unit.
			Adjust as necessary.
			1. Tighten all screws around burner compartment
			2. Cracked heat exchanger. Replace.
			3. Unit over--fired. Reduce input (change orifices
Poor flame characteristics	Incomplete combustion results in: Aldehyde odors,		or adjust gas line or manifold pressure).
	carbon monoxide, sooting flame, floating flame		4. Check burner alignment.
			5. Inspect heat exchanger for blockage. Clean
			as necessary.

577D-- -- A

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