-13-
• Air stream too weak
• Air steam hits obstruction
• Negative pressure
• Shaft rotating inside fan
• One motor not operating
• Nozzle not angled out far enough
• Unit too powerful
• Air movement too cold
• Pushing air outside building
SEE
AIR
IS NOT HITTING FLOOR
SYMPTOMS
• Switch turned to “ON” position
• Thermostat not set properly
• Coils burned out due to lack of air
• Automatic reset thermal cutout failed in open position
• Manual reset thermal cutout tripped (if supplied)
• Adjust nozzle to proper position, adjust motor speed;
see installation instructions
• Remove obstruction or reposition air curtain (move out
3/8” for every 1” up from the door)
• Relieve negative pressure by providing makeup air
• Tighten set screws
• Repair or replace motor
• Adjust nozzle angle to outside
• Adjust motor speed
• Add auxiliary heat to overcome wind chill factor
• Adjust discharge angle back into building, adjust motor
speed
• Replace switch or check wiring
• Change thermostat setting
• Correct airflow problem; replace coils
• Replace automatic thermal cutout
• Reset manual thermal cutout
AIR IS NOT HITTING
FLOOR
UNEVEN AIR
EXCESSIVE AIR
MOVEMENT AT DOOR-
WAY
ELECTRICALLY HEATED MODELS
NO HEAT
MINIMAL HEAT
EXCESSIVE HEAT
STEAM/HOT WATER HEATED UNITS
EXCESSIVE HEAT
MINIMAL HEAT
NO AIR
• Power supply line open (no power)
• Fuse blown/circuit breaker tripped
• Motor overload tripped
• Failed switch
• Check power source, check method of control in ON
position
• Replace fuse(s)/reset breaker
• Internally protected motor - should reset automatically
after cool-down, if not, replace motor.
• Replace switch
MOTOR RUNNING/FANS ARE NOT ROTATING
MINIMUM AIR
ELECTRICAL CONTROLS NOT FUNCTIONING WHEN DOOR IS OPEN
SYMPTOMS
REMEDY
CAUSE
• Broken or damaged flexible hub
• Shaft rotating inside fan
• Selector switch is in off position
• Door limit switch not operating
• Air directional discharge vanes mis-adjusted
• Inadequate intake clearance
• Blower motor operates below speed
• Fan rubbing against housing
• Fan wheels clogged with dirt
• Fan in backwards
• Replace fan sleeve/reengage coupling
• Tighten set screws/tighten fan on shaft
• Turn switch to “ON” position
• Repair or replace limit switch
• Adjust vanes to proper position, see instructions
• Move air curtain or remove obstruction
• Provide adequate space for air curtain
• Improper voltage
• Free fan from housing
• Clean and vacuum fan wheels
• Check fans for blade curve toward discharge
• Thermostat in wrong location - thermostat too
close to discharge
• Improper voltage
• Thermostat not set properly
• Low entering air temperature
• Incorrect speed range
• Thermostat in wrong location
• Thermostat not set properly
• Insufficient air over coil
• Improper voltage
• Too high steam/hot water pressure
• Inadequate air flow, fins plugged up, dirty coils
• Insufficient removal of condensation (steam)
• Not enough steam pressure/water temperature too
low
• Intake air below design temperature
• Move thermostat away from air stream
• Supply proper voltage
• Change temperature setting
• Based on unit temperature rise, reduce speed
• Set dip switch to electric heated speed range
• Move the thermostat closer to air stream
• Change temperature setting
• Remove restriction on intake
• Supply proper voltage
• Reduce steam pressure/hot water flow
• Clean intake and coils
• Increase trap size
• Raise pressure for steam/increase water flow
• Increase steam pressure/increase water flow
X. TROUBLESHOOTING
