Troubleshooting - Mr. Heater MHVFRD10NG Operating Instructions And Owner's Manual

TROUBLESHOOTING

NOTE: All troubleshooting items are listed in order of operation and likely occurrence.
WARNING: Only a qualified service person should service and repair heater.
CAUTION: Never use a wire needle, or similar object to clean ODS/pilot. This can damage ODS/pilot unit.
Make sure grille guard is in place before running heater. If screen or grille guard is removed for servicing it must be
replaced prior to operating the heater.
WARNING: If you smell gas:
• Shut off gas supply
• Do not try to light any appliance
• Do not touch any electrical switch; do not use any phone in your building
• Immediately call you gas supplier from a neighbor's phone. Follow the gas supplier's instructions.
• If you cannot reach your gas supplier, call the fire department.
IMPORTANT: Operating heater where impurities in air exist may create odors. Cleaning supplies, paint, paint remover,
cigarette smoke, cements and glues, new carpet or textiles, etc., create fumes. These fumes may mix with combustion air and
create odors and possible discoloration of walls and ceilings.
OBSERVED SYMPTOM
When ignitor button is
pressed in, there is a spark
at the ODS/pilot but no
ignition
Burner does not light after
ODS/pilot is lit
Delayed ignition of burner
Burner backfiring during
operation
Burner plaque(s) does not
glow [Infrared Only]
Slight smoke or odor
during initial operation
Unvented Natural Gas Fired Room Heater
POSSIBLE CAUSE
Control knob not fully pressed in
Control knob not pressed in long enough
Equipment shutoff valve not fully open
Thermocouple connection loose at
control valve
Pilot flame not touching thermocouple,
which allows thermocouple to cool,
causing pilot flame to go out. This
problem could be caused by one or both
of the following:
a. Low gas Pressure
b. Dirty or Partially clogged ODS/pilot
Thermocouple damaged
Control valve damaged
Burner orifice is clogged
Burner orifice diameter to small
Inlet gas pressure is too low
Manifold pressure is too low
Burner orifice is clogged
Burner orifice is clogged or damaged
Burner damaged
Gas regulator defective
Plaque damaged
Control knob set between locked
positions
Inlet gas pressure is too low
Residues from manufacturing process
REMEDY
Press in control knob fully
After ODS/pilot lights, keep control knob pressed in for 30
seconds
Fully open equipment shutoff valve
Hand tighten thermocouple nut until snug, and then tighten
1/4 turn more
a. Contact local gas company
b. Clean ODS/pilot (see Cleaning and Maintenance, page 1 1)
Replace thermocouple
Replace Control valve
Clean burner orifice (see Cleaning and Maintenance on page
11), or replace burner orifice
Replace burner orifice
Contact local gas company
Contact local gas company
Clean burner orifice (see Cleaning and Maintenance on page
11), or replace burner orifice
Clean burner orifice (see Cleaning and Maintenance on page
11), or replace burner orifice
Replace burner
Replace gas regulator
Replace burner
Turn control knob until it locks at desired setting.
Replace gas regulator
Problem will stop after a few hours of operation
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Installation Instructions and Owner's Manual