Reznor SCE Unit Installation Manual - Manual (Page 31)

Form RZ-NA I-SCE, Mfg #207697 Rev 7, Page 31
Check installation
after startup:
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 24. If shutter adjustment will not reduce yellowing, check for gas
leaks at the control manifold or orifice fitting.
Turn the unit off and on, pausing two minutes between each cycle. Observe for smooth
ignition. On two-stage or modulating burner systems, manipulate temperature adjustment
slowly up and down to see if control is sequencing or modulating properly. Raising
temperature setting drives burner on or to full fire.
Using a manometer or slant gauge readable up to 14" w.c., check orifice manifold for
operating pressure on full fire. Natural gas should be 3.5" w.c. at this point. Propane gas
should be 10" w.c. at this point. Variations from these pressures are not recommended, as
ignition and efficiency performance can be adversely affected by improper pressure
adjustment. See Paragraph 10.
If the system is equipped with an optional dirty filter switch, set the switch. Follow the
instructions in Paragraph 27A.
Place "Owner's Envelope" containing Limited Warranty Card, this booklet, and any optional
information in an accessible location near the heater. Follow the instructions on the
envelope.
Operating Sequence
1. Set the thermostat switch at its lowest setting.
2. Turn on power.
3. Turn on the manual gas valves.
4. Set thermostat at desired setting.
5. Thermostat calls for heat
(a) The venter motor is energized after 15-second (approximate) time delay.
(b) Venter flow switches from N.C. to N. O. contacts, energizing the pilot gas valve
and spark gap to produce a pilot flame on each operating cycle. The sensing probe
proves the presence of the pilot flame and energizes the safety switch portion of
the control. The switch action de-energizes the spark gap and energizes the main
valve. The main gas ignites and the unit fires at full rate.
(c) If the flame is extinguished during main burner operation, the safety switch closes
the main valve and recycles the spark gap. On unit equipped with a G770NGC-4
controller which includes lockout control, if the pilot is not established within 120
seconds (approximately), the unit locks out and must be reset by interrupting the
power to the control circuit (See Lighting Instructions).
6. Blower motor operates from fan time delay.
7. Thermostat is satisfied.
(a) Solenoid gas valve de-energized.
(b) Pilot gas valve de-energized.
(c) Ignition controller de-energized.
(d) Time delay relay keeps venter motor on for approximately one minute (post purge).
8. To shut down, set thermostat to lowest setting. Blower motor remains on as determined by
fan time delay.
DANGER: The gas burner in this gas-fired equipment is designed and equipped to provide safe, controlled
complete combustion. However, if the installation does not permit the burner to receive the proper supply
of combustion air, complete combustion may not occur. The result is incomplete combustion which produces
carbon monoxide, a poisonous gas that can cause death. Safe operation of separated-combustion, indirect-
fired gas burning equipment requires a sealed, properly operating vent system which vents all flue products
to the outside atmosphere. FAILURE TO PROVIDE PROPER VENTING WILL RESULT IN A HEALTH
HAZARD WHICH COULD CAUSE SERIOUS PERSONAL INJURY OR DEATH.
Install either the horizontal or vertical combustion air/vent system illustrated in Paragraph 9 using the
concentric adapter supplied. Always comply with the combustion air requirements in the installation codes
and instructions. Combustion air at the burner should be regulated only by manufacturer-provided
equipment. NEVER RESTRICT OR OTHERWISE ALTER THE SUPPLY OF COMBUSTION AIR TO
ANY HEATER. CHECK THE COMBUSTION AIR/VENT SYSTEM FOR SOUNDNESS AND
FUNCTION; MAINTAIN IT IN PROPER OPERATING CONDITION.