Service & Troubleshooting - Modine Manufacturing POR Installation And Service Manual

service & trouBlesHooting
WARNING
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. Refer to the rating plate on the
appliance for complete appliance model number, serial
number, and company address. Any substitution of parts or
controls not approved by the factory will be at the owner's risk.
table 18.1 - troubleshooting
Problem a. unit does not operate.
1. No oil.
2. Electric circuit in open position.
3. Blown fuses.
4. Burner motor runs but no spark.
5. Defective or incorrect wiring.
6. Defective thermostat or switch.
7. Primary control locked out on safety.
8. Defective cad cell.
9. Burner or fan motor out on overload.
Problem B. unit starts and shuts off.
1. Clogged nozzle.
2. Air leaks in suction line.
3. Faulty ignition.
4. High draft, too much air.
5. Improper oil pressure.
Problem c. fan operates but burner does not operate.
1. Manual fan switch is on.
2. See burner service diagnosis.
3. See fuel pump service diagnosis.
Problem d. Burner operates but fan does not operate.
1. Fan motor failure.
2. Loose fan.
3. Defective fan switch in fan limit control.
4. Defective or incorrect wiring.
Problem e. insufficient heat.
1. Too few units for heat loss.
2. Unit mounted too high.
3. Fan operates backwards.
Problem f. loud noise during starting.
1. Water in oil.
2. Delayed ignition.
Problem g. fuel oil odors.
1. Oil or air leak in supply system.
2. Down draft blowing out of barometric
regulator.
3. Improper flame adjustment.
4. Delayed ignition.
5. In adequate combustion air/ventilation.
oil Burner assembly
Problem a. Burner motor does not start.
1. Incomplete electrical circuit.
2. Primary control locked out on safety.
3. Motor bearings frozen.
4. Motor off/on thermoprotector.
18
Do not attempt to reuse any mechanical or electrical
controllers which have been wet. Replace defective controller.
To check most of the Possible Remedies in the troubleshooting
guide listed in Table 18.1, refer to the applicable sections of
the manual.
1. Fill oil tank or open supply valve or check filter.
2. a. Turn on switch or thermostat.
b. Move thermostat to higher setting.
c. Replace fuse or reset disconnect switch.
3. Replace fuses.
4. Check electrode spacing or replace ignitor.
5. Check wiring and connections. Refer to diagram.
6. Check continuity with volt-ohmmeter. Replace defective part if necessary.
7. Push reset button on primary control only if heat exchanger is cool. Try this only twice.
See control service instructions.
8. Replace cad cell if necessary. Check continuity.
9. Check voltage wiring and motor. Reset overload button on burner motor. Fan motor automatically reset.
1. Replace nozzle.
2. Tighten all fittings.
3. a. Reset electrodes in burner assembly. Check insulators.
b. Check wiring at primary control.
c. Replace ignitor, if required.
4. Check draft regulator adjustment. Adjust combustion air openings on burner.
5. Adjust fuel pump with pressure and vacuum gauges.
1. Turn off manual fan switch.
2. See burner service diagnosis.
3. See fuel pump service diagnosis.
1. a. Check for loose electrical connections. Check wiring with diagram on rear of heater.
b. Repair or replace burned out or defective motor.
c. Voltage too high or too low. Check voltage with voltmeter.
2. Tighten fan set screw.
3. Replace entire control.
4. Check all wiring and connections. See diagram on rear casing panel.
1. Add more units or use larger size units.
2. Lower units.
3. Replace motor.
1. Bleed line at fuel unit. Replace supply if necessary
2. a. Reset electrode gaps.
b. Nozzle worn or dirty. Replace nozzle.
c. Check voltage drop when burner motor starts. High current draw can result in weak spark from
transformer.
d. Inspect ignitor and wiring.
e. Check to assure positive contact between transformer terminals and electrode buss bars.
1. Tighten all fittings and check for leaking supply valve stems.
2. a. Check for blocked chimney or vents.
b. Check regulator setting and adust to correct.
3. Inspect flame through inspection port. Adjust burner air openings and/or fuel oil pressure.
4. See F-2.
5. See recommendations for outdoor air openings. Page 4.
1. Check main disconnect switch, fuses, thermostat contacts, and operating and limit controls.
2. Wait five minutes and until heat exchanger is cool. Actuate external reset on relay. Determine cause for
lock-out and correct.
3. Free shaft and lubricate.
4. Allow motor to cool and push reset button. If motor cuts out again, check wiring to locate cause.
4-522.4
CAUTION
IMPORTANT
remedy
remedy