FUTERA FUSION INSTALLATION AND OPERATION INSTRUCTIONS
25
1/16 TO 1/8 OF AN in
1.5 mm TO 3.2 mm
9 1/4 in.
235 mm
FROM BOTTOM OF
SPARK ROD PLATE
RIOM-17-REV-B
SEE DETAIL A
1/4 to 7/8 OF AN in
6.4 mm TO 22.2 mm
FROM TIP TO
BURNER SURFACE
DETAIL A
2 5/16 in
58.8 mm
10 1/8 in
257.2 mm
CHECKING & ADJUSTMENTS
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 17 &18.
Figure 17 – Spark Gap
Figure 18 – Spark Rod Position and Pilot Flame
Pilot Adjustment
The pilot pressure has been factory set at 2" and shouldn't
need adjustment. To check the pilot pressure close the
manual main shut-off valve 2 and the pilot gas shut-off
valve, Figure 14. Remove the 1/8" pipe plug from the pilot
tee and connect a manometer having a minimum range of
6 in
,
152 mm
WC to it. Open the pilot gas shut-off valve.
With the unit powered, generate a call for heat. When the
prepurge is complete the ignition/pilot trial will begin. At this
point put the Honeywell RM7800 test switch in the test
position. The control will hold in the ignition/pilot sequence
allowing you to check the pressure.
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 pressure and counterclockwise to
decrease it.
3. Replace the pressure regulator adjustment screw cap.
CAUTION: Never force the regulator adjustment screw
beyond the stop limits or damage to the regulator will
occur!
WARNING: The air damper adjustments must
only be made by a trained technician using a
combustion analyzer! Improper adjustment can
result in excessive levels of carbon monoxide or
an explosion resulting in severe personal injury
or death!
Required Gas Pressure
Provide gas supply pressure at inlet to boiler gas train as
follows:
LP
Nat
Minimum (in W.C.)
2
2
Maximum
(in
W.C.) 14
14
Measure pressure when the boiler is fi ring at full rate. Low
gas pressure could indicate undersized gas line or
insuffi cient gas supply.
“Static and operating gas pressure required at the gas
valve inlet is between 2" W.C. and 14" W.C. for natural gas
and 2" W.C. and 14" W.C. propane. If the gas pressure is
above this limit, a lock-up style regulator suitable for dead
end service such as an Equimeter or Fisher must be
installed to prevent increase (creep) of gas pressure when
the units are not operating. This pressure regulator
(supplied by others) may be installed at the service
entrance to each unit or a “master” regulator sized to
handle multiple units may be utilized. Consult local gas
utility or regulator manufacturer for recommendations to
meet specifi c job site requirements.”
Input Rate, Natural Gas
Gas appliances are rated based on sea level operation with
no adjustment required at elevations up to
2000 ft
,
610 m
.
At elevations above
2000 ft
,
610 m
input ratings should
be reduced by 4% for each
1000 ft
,
305 m
.
Check the input rate as follows:
1. Turn off all other gas appliances that use the same gas
meter as the boiler/water heater.
2. Call your gas supplier and ask for the heating value
of the gas.
3. Start the boiler/water heater and let it run for 15
minutes.
4. Using the gas meter and a stopwatch, clock the time
that it takes to burn
10 ft
3
,
0.28 m
3
of gas and divide
this time by 10.
5. Insert the heating value and the time, in seconds, into
the formula below.
6. Input = (heating value, Btu/hr)(3600)/(time, seconds)
7. If the computed rate deviates by more than 5% from
the rated input value of the unit, consult factory.
CAUTION: Never increase the input to the boiler/water
heater above that for which it is rated. Doing so can
cause premature failure of the boiler!
