5
CONTROL WIRING:
Connect thermostat to terminals R and W for heating, R and G for cool air only. This can be done
with a single stage heat-cool thermostat or a single stage heat-only thermostat and a separate fan-only switch to control
the optional fan-relay installed on furnaces. Some models of furnace have optional two stage operation and are provided
with terminals W1 and W2. If a single stage thermostat is used it should be connected to terminals R and W1 and a jumper
wire installed from terminals W1 to W2
(see enclosed control circuit wiring diagram)
. Some models of furnace have the
24 VAC power available between terminal C and R for use with the external air conditioning blower relay option.
OPERATION:
When the control thermostat is turned up to demand heat the blower and heating elements should be
energized. Furnaces with sequences installed will have up to 30 seconds delay in start-up. When turned to cool position
heat-cool thermostats should bring on the blower only for cooling air.
MAINTENANCE
"CAUTION"
Disconnect power at the main service panel before inspecting or cleaning this heater.
Lock or tag breaker to prevent accidental shock.
Because of its rugged design, superior engineering and quality craftsmanship and manufacturing the King KF-KFS Furnace
requires little maintenance. With proper care your electric furnace should last a lifetime. To maintain the efficiency of
the heater King recommends changing the air intake filter at least twice a year and checking the motor and blower for
excessive dust / lint accumulation - your environment may require more frequent changes.
TROUBLESHOOTER
TROUBLE
POSSIBLE CAUSE
REMEDY
Unit will not start
Motor will not stop
Unit goes off on high limit
Vibration noise
Unit has a buzzing sound
when not in use
Unit continues to heat after
room is up to set temperature
- does not shut off
• Thermostat wire is not connected
• Circuit breaker is off
• 24 Volt transformer burned out
• Wire connection off or there are
broken
wires
• Reset button tripped
• Wrong voltage
• Repair
• Reset
• Replace
• Repair or replace
• Reset
• Check the power source
• Defective sequencer or contactor
• Replace
• Dirty air filter / ducts
• Defective sequencer
• Defective limit control
• Power failure
• Replace
• Replace
• Replace
• Reset manual limit push
button 20-35 kW units
• Blower assembly loose
• Secure blower and motor cage
• Low voltage transformer
defective or loose
• Replace or tighten
• Defective sequencer
• Defective thermostat
• Thermostat wires to ground
• Motor wires to ground
• Thermostat accidentally shorted
& contacts are welded
• Replace
• Replace
• Repair
• Repair
• Replace
- Make sure all connections are tight
Unit short cycles before
thermostat calls for off
• Thermostat anticipator set too low
• Intermittent opening of thermostat
or its wires
• Heat element burned out
• Circuit breaker off
• Motor overheating
Runs too often,
Blows cold air
• Adjust to .04 Amps for each sequencer
in furnace
• Repair or replace thermostat
• Replace
• Reset
• Motor overheating
• Replace with adjustable anticipated thermostat
• Lower CFM of motor
Red wire - low speed
Blue wire - medium speed
Black wire - high speed
• KFS5-18 should have 1/5 HP motor;
1/2 and 3/4 HP motors are optional
• Thermostat heat anticipator set too low
• CFM of motor set too high
• Motor overheating
NOTE: When converting from oil, gas, etc. to electric, replace your old low voltage fixed-heat anticipator thermostat with one that has an adjustable heat anticipator.
2007 KF-KFS.indd : 10/07
