General Maintenance & Troubleshooting - Modine Manufacturing AMP Installation And Service Manual

GENERAL MAINTENANCE / TROUBLESHOOTING
CAUTION
WARNING
1. When servicing or repairing this equipment, use only
factory approved service replacement parts. A complete
replacement parts list may be obtained by contacting
Modine Manufacturing Company. Parts not approved by the
factory will be at the owner's risk.
2. Do not operate any heater if it malfunctions. Disconnect
power at service panel and have heater inspected by a
qualified installation and service agency.
3. Do not reuse any electrical component which has been wet.
Such component must be replaced.
Replacement parts can be obtained from Modine by submitting
the model number, power code, control code and serial number
shown on the rating plate attached to the unit, along with a
description of the part.
Table 8.1 - Troubleshooting
PROBLEM
Unit does not operate 1.
2.
3.
4.
5.
6.
1.
2.
F a n o p e r a t e s b u t
3.
element does not heat
1.
2.
3.
4.
Elements heat but fan
does not operate
1.
2.
Insufficient heat
3.
4.
8
POSSIBLE CAUSE(S)
Electric circuit in open position.
Tripped breaker or fuse of circuit.
Defective or incorrect wiring.
Defective thermostat or switch.
Defective or burned out control transformer
Defective control board
Power interrupted by overheat control.
Unit receiving fan only call.
Defective or incorrect wiring.
Blown motor fuse
Fan motor failure
Summer-winter switch defective or
improperly wired.
Defective or incorrect wiring.
Too few units or under sized unit(s) for heat
loss.
Unit(s) mounted too high.
Airflow too low.
Burned out element.
Routine Unit Maintenance
Under average conditions, it is recommended that unit heaters
be serviced at least once a year and checked out prior to the
heating season. In excessively dirty atmospheres, service
should be performed more often.
1. Disconnect power supply to the unit before performing any
of the following maintenance or inspection procedures & allow
heating elements of heater to cool.
2. Check all components and wiring inside the unit for firm
connections and/or wear.
NOTE: To check most of the Possible Remedies in the
trouble-shooting guide listed in Table 8.1, refer to the
applicable sections of the manual.
3. Verify unit mounting is secure, and tighten any hardware that
seems loose.
4. Fan motor is permanently lubricated for normal operation.
Under severe conditions, lubricate with non-detergent
SAE 20 motor oil.
5. Routine cleaning of the unit casing and outlet screen is
recommended to remove dirt, grease, or corrosive substances
that may damage the finish. Rusted or corroded spots on the
outlet screen or casing should be sanded and repainted.
6. Check entire electrical system before every heating season.
1. a. Turn on switch or thermostat
b. Move thermostat to higher setting.
c. Replace fuse or reset disconnect
2. Replace fuses or reset breaker
3. Check wiring and connections. Refer to diagram inside
control panel.
4. Check continuity with volt-ohmmeter. Replace defective part
if necessary.
5. Check secondary voltage with voltmeter. Replace if
necessary.
6. Replace if necessary
1. Defective limit control. Check wiring and connections. Check
continuity through control. Replace if necessary.
2. Check thermostat settings, wiring and connections.
3. Check all wiring and connections. See diagram inside access
panel.
1. Check fuse on control board, replace if necessary
2. a. Check for loose electrical connetions. Check wiring with
diagram in control compartment.
b. Repair or replace defective motor.
c. Voltage too high or too low. Check voltage with voltmeter.
3. Check for continuity with volt-ohmmeter. Replace if
necessary.
4. Check all wiring and connections. See diagram inside contol
compartment.
1. Add more units or increase size of unit(s)
2. Lower unit(s)
3. Check motor rpm against namplate rating. Replace motor if
speed is too slow
4. Disconnect internal wiring and check individual element
resistance with ohmmeter (50.5 ohms +/- 5%).
2-529.0
REMEDY