Service & Troubleshooting - Modine Manufacturing PDP 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 5.1 - troubleshooting
trouble
Pilot does not light
main burners do not light (Pilot is lit)
lifting flames (see figure 6.)
Yellow tipping
(With propane gas, some yellow tipping
is always present.)
Wavering flames (see figure 6.1)
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 25.1, refer to the applicable sections of the
manual.
Possible cause
1. Main gas is off.
. Power supply is off.
3.
Air in gas line.
4.
Dirt in pilot orifice.
5. Gas pressure out of proper range.
6. Pilot valve does not open.
a. Defective ignition controller.
b. Defective gas valve.
7.
No Spark at ignitor.
a. Loose wire connections.
b. Pilot sensor is grounded.
c. Defective ignition controller.
8. Safety device has cut power.
9. Pilot valve is off.
10. Dirty thermocouple contact.
11. Excessive drafts.
1. Pilot orifice Fitting leak.
1.
Defective valve.
. Loose wiring.
3. Defective pilot sensor
4. Defective ignition controller.
5.
Improper thermostat wiring.
1. Too much primary air.
. Main pressure set too high.
3. Orifice too large.
1.
Insufficient primary air.
. Dirty orifice.
3. Misaligned orifice.
1.
Drafts across burner
.
Misalignment of burner
3. Cracked heat exchanger
6-580.4
CAUTION
IMPORTANT
Possible remedy
1. Open manual gas valve.
. Turn on main power.
3.
Purge gas line.
4.
Check for plugged pilot orifice and clean
with compressed air if necessary.
5. Adjust to a maximum of 14" W.C.
Minimum for Natural Gas - 6" W.C.
Minimum for Propane Gas - 11" W.C.
6. Check wiring for 24 volts to valve.
a. Replace ignition controller.
b. Replace gas valve.
7.
a. Check all ignition controller wiring.
b. Replace sensor if cracked or worn
c. Replace ignition controller.
8. Check all safety devices (High limit,
pressure switch, blocked vent safety
switch, etc.) Determine and correct
problem. Reset if necessary.
9. Turn gas control knob or lever on
combination gas control to pilot position.
10. Be sure thermocouple contact is clean.
If problem persists replace thermocouple.
11. Find source and re-direct airflow away
from unit.
1. Tighten pilot orifice. Flame impingement
on thermocouple may cause
thermocouple to become inoperative.
1.
Replace valve.
. Check wiring to gas valve.
3. Replace pilot sensor.
4. Replace ignition controller.
5.
Verify wiring compared to wiring diagram.
1. Reduce primary air.
. Adjust to a maximum of 14" W.C.
3. Check orifice size with those listed on
the serial plate.
1.
Increase primary air.
.
Check orifices and clean with
compressed air if necessary.
3. Check manifold, replace if necessary.
1.
Eliminate drafts
. Align burner on locator pins
3. Replace heat exchanger
5