Reznor SC Duct Furnace Unit Installation Manual - Manual (Page 38)

Form I-SC, P/N 207696 R11, Page 38
TROUBLE PROBABLE CAUSE REMEDY
Pilot will not light
-- Venter operating
(cont'd)
a) Loose wire connections a) Be certain all wires connections are solid.
b) Transformer failure. b) Be certain 24 volts is available.
c) Incorrect spark gap. c) Maintain spark gap at .100".
d) Spark cable shorted to ground. d) Replace worn or grounded spark cable.
e) Spark electrode shorted to ground. e) Replace pilot if ceramic spark electrode is cracked or
grounded.
f) Drafts affecting pilot. f) Make sure all panels are in place and tightly secured to
prevent drafts at pilot.
g) Ignition control not grounded. g) Make certain ignition control is grounded to furnace
chassis.
h) Faulty ignition controller. h) If 24 volt is available to the ignition controller and all other
causes have been eliminated, replace ignition control.
8. Optional lockout device interrupting control
circuit by above causes.
8. Reset lockout by interrupting control at thermostat.
9. Faulty combustion air proving switch. 9. Replace combustion air proving switch.
Pilot lights, main
valve will not open
1. Manual valve not open. 1. Open manual valve.
2. Main valve not operating. 2.
a) Defective valve. a) If 24 volt is measured at valve connections and valve
remains closed, replace valve.
b) Loose wire connections. b) Check and tighten all wiring connections.
3. Ignition control does not power main valve. 3.
a) Loose wire connections. a) Check and tighten all wiring connections.
b) Flame sensor grounded. (Pilot lights -
spark continues)
b) Be certain flame sensor lead is not grounded or insulation
or ceramic is not cracked. Replace as required.
c) Gas pressure incorrect. c) Adjust gas pressure. (See Paragraph 6.2.)
d) Cracked ceramic at sensor. d) Replace sensor.
e) Faulty ignition controller. e) See Paragraph 10.2.4. If all checks indicate no other
cause, replace ignition controller. Do not attempt to repair the
ignition controller. This device has no field replaceable parts.
No heat (Heater
operating)
1. Dirty filters in blower system. 1. Clean or replace filters.
2. Incorrect manifold pressure or orifices. 2. Check manifold pressure (See Paragraph 6.2).
3. Cycling on limit control. 3. Check air throughput (See Paragraph 6.4).
4. Improper thermostat location or
adjustment.
4. See thermostat manufacturer's instructions.
5. Belt slipping on blower 5. Adjust belt tension
6. Fan control improperly wired 6. Connect as per wiring diagram.
7. Defective fan control. 7. Replace fan control.
8. Blower set for too low temperature rise. 8. Slow down blower or increase static pressure.
10.3 Troubleshooting (cont'd)
10.0 Maintenance and Service (cont'd)