Slant/Fin GXHA-200 - Manual (Page 11)

11 GALAXY STEAM BOILER
BURNER ADJUSTMENT
A.Adjust gas input rate:
1. Consult gas supplier for heating value of gas (Btu/cu.ft.).
2. Set thermostat high enough so that boiler will remain on
while checking rate.
3. Measure manifold pressure at 1/8" tapping. Correct
manifold pressure for gas used is printed on boiler rat-
ing plate. NOTE: Gas pressure may be adjusted by
turning pressure regulator screw on combination gas
valve (Turn clockwise to increase pressure, counter-
clockwise to decrease pressure).
a. Input for PROPANE is approximately at rating shown
on rating plate when manifold pressure is 9-1/2" water
column.
b. Input for NATURAL GAS is approximately at rating
when manifold pressure is 3-1/2" water column, but
should be checked on the gas meter:
Btuh Input = Btuh/cu. ft. x cu. ft. metered in 3 minutes
x 20
Example #1:
For 1000 Btu/cu. ft. gas, this becomes:
Btuh Input = cu. ft. metered in 3 minutes x 1000
Btu/cu.ft. x 20
Example #2:
For 1050 Btu/cu. ft. gas, this becomes:
Btuh Input = cu. ft. metered in 3 minutes x 1050
Btu/cu.ft. x 20
4. The higher* heating value of gas varies substantially for
different localities. Consult with Slant/Fin’s Technical
Service Dept. for re-orificing procedures if any of the fol-
lowing apply:
a. Boiler (burner) is overfiring.
CAUTION ! National Fuel
Gas Code (ANSI Z223.1-latest edition) does NOT
permit firing at a higher input rate than the input rate
indicated on the boiler rating plate in order to avoid
hazardous conditions such as explosion or carbon
monoxide poisoning.
b. Poor higher* heating value of gas is causing the actu-
al input to be substantially lower than the rating plate
indication.
* “Higher heating value” of gas is commonly known as “heating
value”
GAS RATE TABLE
The gas metered in 3 minutes to obtain rated input for each
boiler model, using 1000 Btu/cu. ft. gas is tabulated in gas rate
table.
B.Main Burner
1. Fire the boiler continuously for at least 15 minutes, to
reach burner operating temperature.
2. Observe the flames, all burners. The base of all flame
jets should be blue. The tips should be blue shading to
orange. NOTE: Dust, disturbed by any movement, will
cause bright orange flames. Wait for dust to settle.
3. For one burner, close the air shutter until some of its
flame jet tips turn yellow-white, indicating insufficient pri-
mary air. Then open shutter until whitish tips disappear
completely. Set all burner shutters to the same opening.
Observe to make sure that no yellow-white tips appear
over any portion of the flame. Small yellow tips at the
pilot location are permitted.
NOTE: This adjustment method gives MINIMUM primary
air setting for safe combustion. DO NOT attempt to make
this adjustment unless burners are at operating tempera-
ture. Adjustment should be made with jackets in final
operating position. Use of mirror may be helpful to
observe flames. Note that burner ports are on top of main
burner tube.
C.Main Burner Ignition Check-out and Pilot Adjustment
1. The pilot flame must not smother or snuff out when test-
ed as follows:
a. Main burner ignition from cold start-repeat.
b. Continued operation of main burner.
c. Main burner ignition with appliance at maximum oper-
ating temperature after prolonged operation.
NOTE: Observe operation of the pilot burner with appli-
ance doors in the final operating position. Use of a mir-
ror may be helpful.
2. Safety Shutdown Check-out
a. For proper operation the pilot should engulf the ther-
mocouple, powerpile generator or flame sensor as
shown below.
b. To adjust pilot, turn pilot flow adjustment screw on
valve clockwise or counterclockwise to give a steady
flame enveloping 3/8" to 1/2" of the tip of the thermo-
couple, generator or flame sensor. Note that turning
the pilot adjustment screw clockwise will decrease the
pilot flame.
c. Check safety shutdown of gas valve by following proce-
dure outlined "CARE AND MAINTENANCE" section.
100 5.00
120 6.00
125 6.25
150 7.50
160 8.00
175 8.75
200 10.00
225 11.25
250 12.50
275 13.75
300 15.00
Boiler rated input in
cu. ft./hr. of 1000 Btu/cu.ft.
Natural Gas
Cubic Feet Gas Consumption
1000 Btu/cu. ft. gas, in 3 min-
utes, at rated output