NATURE
OF
TROUBLE CORRECTIVE
MEASURES
2. Main gas valve stuck in open position or inoperative
Remove MV lead at ignition module. If valve does not
module.
close, replace valve or operator as necessary. If main
gas
valve
and
thermostat/controller
are
okay,
replace
module.
·
Delayed or Rough Ignition:
1. Obstruction in main burner spuds.
Remove spuds, clean, and replace.
2. Burners covered with foreign matter.
Clean burners. See CLEANING on pages 11 and 12.
·
Burner Flames Flashback and Burning at Spuds:
1.
Gas
input
too
low.
Adjust
pressure regulator or increase supply pipe size
to
unit.
It
may
be
necessary to consult gas company.
2. Burners or flue tubes covered by foreign matter.
See CLEANING on pages 11 and 12. If faulty, consult
manufacturer.
·
Burner Flames Are Yellow or Tend to “Float” under Flue Tubes:
1. Gas input too high due to oversize main burner spuds
Consult manufacturer for proper spud size before
or gas supply pressure in excess of 8 ounces (approx-
changing or gas company before adjusting regulator or
imately
14” W.C.)
decreasing size of supply piping to unit.
2. Dirty burner ribbons or flue tubes.
See CLEANING on page 11 and 12.
3. Insufficient combustion air.
Make sure air inlets of unit are open. Clean unit. If
condition
still
exists, see item 1 of INSTALLATION
PRECAUTIONS.
·
Blower Fails to Operate within 2 Minutes after Burners Ignite:
1. Faulty blower wiring/connections, motor, or fan
Inspect and correct wiring/connections as necessary.
controls.
Connect line voltage directly to motor. If motor operates,
replace
fan
control
if
non-adjustable.
2. Fan control set too high.
Adjust setting.
3.
Thermostatic
fan
control.
See
modulating
or two-stage gas controls, item 10 of
INSTALLATION
PRECAUTIONS.
·
Insufficient Heat Delivery from Furnace:
1. Undersized spuds or manifold pressure below mark-
Consult manufacturer for proper spud size before
ing on specification plate.
changing or gas company before adjusting regulator. Be
sure gas supply pipe size to unit is adequate.
2. Inadequate air delivery from blower.
Check for slipping belts and proper blower speed,
plugged filters (if used), dirty blower impeller blades, or
any
airflow
obstructions and excessive system static
pressure. Correct as necessary.
3.
Dirty
flue
tubes.
Clean tubes. See CLEANING on page 10.
·
Furnace Overheats or Cycles on Limit Switch:
1. Main gas valve faulty. Stuck in open position.
Replace main valve or operator.
2. Faulty limit switch or fan control (if used).
Inspect and replace as necessary.
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