SECTION SEVEN – Troubleshooting
7-9
Burner Troubleshooting
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CCCCAAAAUUUUSSSSEEEE
RRRREEEEMMMMEEEEDDDDYYYY
Loud, high-pitched whine
Flame is too rich.
Verify pressure tap between gas valve
and blower inlet.
Verify gas regulator setting 0.2" wc
below blower inlet pressure.
Replace gas orifice with ssssmmmmaaaalllllllleeeerrrr size.
Adjust CO2 to 8%-9% for natural gas.
9.2%-10.5% for propane.
Flame is “fluttery.”
Flame is too lean.
Verify gas regulator setting 0.2" wc
Exhaust may have acrid
below blower inlet pressure.
smell or burner may fail
Replace gas orifice with llllaaaarrrrggggeeeerrrr size.
to stay lit.
Adjust CO2 to 8%-9% for natural gas.
9.2%-10.5% for propane.
Burner pulsates on
Exhaust vent is too long.
Reduce length of exhaust vent and/or
surges, especially on
number of elbows.
ignition.
Combustion appears
Flame current is not
Check for wet or damaged igniter with
normal, but flame does
being sensed.
low resistance to ground. Replace with
not stay lit.
new igniter.
Verify burner flameholder is properly
grounded.
Replace Ignition Control Module.
Heat Exchanger Troubleshooting
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CCCCAAAAUUUUSSSSEEEE
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Boiling in heat exchanger.
Low water flow to heater.
Service pump and or filter.
May be accompanied by
Heat exchanger plugged.
Service heat exchanger. Correct water
“bumping” sounds.
chemistry.
Bypass valve stuck open.
Service bypass valve.
Thermal governor stuck
Replace thermal governor.
closed.
Sweating.
Thermal governor failed.
Replace thermal governor.
