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Table 11 – Troubleshooting Chart--Gas Furnace Operation
SYMPTOM
CAUSE
REMEDY
Burners will not ignite
Water in gas line
Drain. Install drip leg.
No power to unit
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 peri-
od to reset.
Mis--wired or loose connections
Check all wiring and wire nut connections
Misaligned spark electrodes
Check flame ignition and sense electrode posi-
tioning.
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 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.
Inadequate heating
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
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.
677D
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--
A
Содержание 677D--A
Страница 5: ...5 A09561 Fig 5 677D A24 30 Unit Dimensions 677D A...
Страница 6: ...6 A09562 Fig 6 677D A36 60 Unit Dimensions 677D A...
Страница 18: ...18 A10217C Fig 17 Connection Wiring Schematic 677D A Single Phase Gas Inputs 040 060 090 kBtu hr 677D A...
Страница 19: ...19 A10217L Fig 16 Cont Ladder Wiring Schematic 677D A Single Phase Gas Inputs 040 060 090 kBtu hr 677D A...
Страница 20: ...20 A10219C Fig 18 Connection Wiring Schematic 677D A Single Phase Gas Inputs 115 130 kBtu hr 677D A...
Страница 21: ...21 A10219L Fig 17 Ladder Wiring Schematic 677D A Single Phase Gas Inputs 115 130 kBtu hr 677D A...