SYMPTOM
Thermostat calls for heat, but heater does not
function.
Fan motor runs "HOT"
Fan motor runs, but no heat.
MAINTENANCE
CAUTION: Make certain that the power source is disconnected before attempting to service or disassemble any
component. If the power disconnect is out of the line of sight, lock it in the OPEN position and tag to prevent the
application of power.
ELECTRICAL
Once a year inspect the control panel wiring to make certain insulation is intact and all connections are tight. Inspect all
heater and relay contacts. If the contacts appear badly pitted or burned, replace the contactor / relay.
CLEANING
Clean the unit casing, fan and motor once a year. A dirty motor will tend to run hot and eventually will be damaged
internally. Any rust spots on the casing should be cleaned and repainted.
LUBRICATION
All units up to 20KW have fan motors that are permanently lubricated so that only occasional cleaning is required. Units
above 20KW have fan motors lubricated for 5 years of continuous duty of 10 years of intermittent operations. When
required, remove the oil access plug on back of heater at motor intake grill, open oil cap, fill with S.A.E. No. 10 electric
motor oil, replace plugs and access plug.
5100 SERIES UNIT HEATER
TROUBLE SHOOTING GUIDE
POSSIBLE CAUSE(S)
1.
Open (blown) fuse
2.
INCORRECT WIRING
3.
Thermal cut-out open, de-energizing heater
element and control circuit.
1.
Dust accumulation or excessive dirt on
motor.
2.
Dirt accumulation
3.
Motor needs lubrication.
1.
Element contactor not operating
correctly.
2.
Element fuse blown.
10 of 20
CORRECTIVE ACTION
1.
Replace fuses, check for cause.
Replacement Parts List for fuse size)
2.
CHECK WIRING CONNECTIONS
3.
Check for the following:
•
Correct supply volts and phase
•
Correct control wiring (heater control
must be thru thermostat control wiring
section only).
•
Power interruption to heater during heater
operation.
•
Restriction of air around heater 1-5 minute
fan purge after thermostat off.
1.
Clean fan motor and casing of grease and
oil accumulation.
2.
Clean
louvers
and
between
elements
3.
See Maintenance.
1.
Check wiring for open circuit.
contactor if defective
2.
Replace fuses, check for cause. (see
Replacement Parts List for fuse size)
(see
heating
Replace
ECO 1-7874
REV. 10/22
FORM: 9632