Reznor X Unit Installation Manual - Manual (Page 23)

Form I-X, P/N 150491 R10, Page 23
9.0 Commissioning
and Startup
9.1 Check the installation prior to startup
 Check suspension. Unit must be secure and level.
 Be certain the electrical supply matches voltage rating of the furnace. (Refer to the
rating plate.)
 Check clearances from combustibles. Requirements are shown in Paragraph 4.2.
 Check vent system to be sure that it is installed according to the instructions in
Paragraph 6.2. Be sure that flue discharge openings are free from obstructions.
 Check piping for leaks and proper gas line pressure. Bleed gas lines of trapped air.
See Paragraph 6.1.
a) Turn manual shutoff valve to off position.
b) Turn gas supply on.
c) Observe gas meter for movement, or
d) Attach pressure gauge readable to .1" w.c. and after turning gas on for 10
seconds, turn the gas off. No change in pressure should occur over a 3-minute
period.
e) If either c) or d) above indicate a leak, locate leak by brushing a soapy solution on
all fittings. Bubbles will appear at a leak. Repair and repeat tests.
NOTE: Prior to 8/2008, a
Model X unit could have an
intermittent spark system
without lockout, Option
AH2. Check the wiring
diagram on the furnace.
9.2 Startup
 Turn electric and gas supply on to the furnace. Adjust the thermostat or ductstat so
that a call for heat exists. Observe for complete sequencing of pilot and ignition.
Operating Sequence for Intermittent Spark Pilot System
1) Set the thermostat switch at its lowest setting.
2) Follow lighting instructions.
3) Set thermostat switch at desired setting.
4) Thermostat calls for heat, energizing the ignition controller and the pilot gas
valve, lighting the pilot. NOTE: If the flame is extinguished during main burner
operation, the safety switch closes the main valve and recycles the spark
gap. If pilot is not established within 120 seconds (approx.), the unit locks
out. At 60-minute intervals, the controller will retry to establish pilot or may be
reset at any time by interrupting the power to the control circuit (See Lighting
Instructions).
5) The sensing probe proves the presence of the pilot flame.
(a) De-energizing the ignitor; (b) Energizing the gas valve.
6) Blower motor operates from fan time delay.
7) Set the thermostat switch at lowest setting for shutdown. Blower motor remains
on as determined by fan time delay.
When making the adjustment, close the air shutters no more than is necessary to elimi-
nate the problem condition.
DANGER:
Failure to install and/or adjust air shutters according to directions could
cause property damage, personal injury, and or death.
9.3 Check
installation after
startup
 With the unit in operation, measure manifold gas pressure. Manifold pressure for
natural gas should be 3.5" w.c. and 10" w.c. for propane gas. See Paragraph 6.1.
 Turn the unit off and on, pausing two minutes between each cycle. Observe for
smooth ignition. On two-stage or modulating burner systems, manipulate tempera-
ture adjustment slowly up and down to see if control is sequencing or modulating
properly. Raising temperature setting drives burner on or to full fire.
 Observe burner flame at full fire. Natural gas flame should be about 1-1/2" in height
with blue coloring. Propane gas flame should be approximately the same length
with blue coloring. Yellow tipping may appear on propane gas. If yellow extends
beyond 1/2 to 3/4", adjust air shutters. See Paragraph 8.6.2.