Checking & Adjustments - RBI FUTERA II Series Installation And Operation Instructions Manual

FUTERA II INSTALLATION AND OPERATION INSTRUCTIONS
CHECKING & ADJUSTMENTS
On initial light-off, the installer may alter the preset factory
settings to attain satisfactory combustion. An accurate
manometer and fl ue gas analyzer must be used. Please
see Fire Testing section 4 for combustion guidelines.
Spark Gap
With the main and pilot gas manual valves in the closed
position energize the unit. Observe the trial for ignition to
confi rm that the spark is strong and continuous. If not,
check and adjust the spark gap as shown in Figures 19 &
20.
Figure 19 – Spark Gap & Pilot Flame
RSUB-75
Figure 20 – Spark Rod Position Detail
Pilot Operation
With the manual main gas valve and manual pilot gas valve
closed energize the unit and allow it to try for ignition until
it goes into fl ame failure. The trial for ignition indicator light
should illuminate immediately after the trial for ignition
starts and stay on for approximately 15 seconds. The trial
for ignition indicator light should go out and the fl ame failure
indicator light illuminate immediately after fl ame failure.
Open the manual pilot gas valve. A normal pilot ignition
sequence should take place within 6 minutes of the initial
fl ame failure. The trial for ignition indicator light should stay
on. Recycle the pilot several times to confirm reliable
operation.
Pilot Adjustment
The pilot burner fl ame should be well defi ned and 2 to
1
2 / in, 50 to 64 mm above the surface of the burner, Figure
2
19. To adjust the pilot the following steps must be taken:
1. Remove the pilot gas pressure regulator cap.
2. Turn the pressure regulator adjustment screw clock-
wise to increase the fl ame and counterclockwise to
decrease it.
3. Replace the pressure regulator adjustment screw cap.
Fire Testing
1. For an on/off unit confi rm that the low-fi re side of the
two-stage gas valve is set to its maximum setting.
For a two-stage unit a 1/16" thick silicon spacer should
be installed under the low-fi re adjusting screw. Without
this spacer it won't be possible to consistently set the
low-fi re pressure to 2.4 in, 61 mm W.C.
2 . Fo l l ow t h e i n s t r u c t i o n s i n t h e " O P E R AT I N G
INSTRUCTIONS" section starting on page 25 to fi re
the main burner. Upon ignition of the main burner
adjust the high fi re adjusting screw to obtain the high
fi re pressure listed in Table 8. On a two-stage unit
disconnect the power from the high fi re side of the gas
valve and adjust the low fi re, regulator. If the unit short
cycles on low fi re adjust the air box pressure and gas
back pressure as outlined below.
CAUTION: Never force the regulator adjustment screw
beyond the stop limits or damage to the regulator will
occur!
Table 8 – Pressure Settings, Inches W.C.
Model Natural Gas
Size Low
in mm in
500 n/a n/a 3.0
750 2.4 61 3.0
1000 2.4 61 3.0
1250 2.4 61 3.0
1500 2.4 61 3.0
1750 2.4 61 3.0
1950 2.4 61 3.0
27
LP Gas
High Low High
mm in mm in
76 n/a n/a 7.0
76 6.0 152 7.0
76 6.0 152 7.0
76 6.0 152 7.0
76 6.0 152 7.0
76 6.0 152 7.0
76 6.0 152 7.0
mm
178
178
178
178
178
178
178