577C--C, 577C--E, 577C--F: Installation Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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Table 17 – Troubleshooting Guide–Heating
SYMPTOM
CAUSE
REMEDY
Burners will not ignite
Water in gas line
Drain. Install drip leg.
No power to furnace
Check power supply fuses, wiring or circuit breaker.
No 24-v power supply to control circuit
Check transformer.
NOTE: Some transformers have internal over-current protection
that requires a cool-down period to reset.
Mis-wired or loose connections
Check all wiring and wire nut connections
Misaligned spark electrodes
Check flame ignition and sense electrode positioning.
Adjust as necessary.
No gas at main burners
1. Check gas line for air. Purge as necessary. NOTE: After
purging gas line of air, wait at least 5 minutes for any gas to
dissipate before attempting to light unit.
2. Check gas valve.
Inadequate heating
Dirty air filter
Clean or replace filter as necessary
Gas input to furnace too low
Check gas pressure at manifold match with that on unit
nameplate
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.
Poor flame characteristics
Incomplete combustion results in: Aldehyde odors,
carbon monoxide, sooting flame, floating flame
1. Tighten all screws around burner compartment
2. Cracked heat exchanger. Replace.
3. Unit over-fired. Reduce input (change orifices or adjust gas line
or manifold pressure).
4. Check burner alignment.
5. Inspect heat exchanger for blockage. Clean as necessary.
