GB100W NATURAL OR PROPANE BOILER | Page 23 |
INSTALLATION AND OPERATING INSTRUCTIONS |
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E.With the burners in operation, interrupt the power to the control circuit by lowering and raising the thermostat. A normal ignition sequence should follow.
F.To test the ignition safety shutoff device, close the manual shutoff valve in the gas supply line. Within 6 seconds of main burner flame extinction, the main gas valve solenoid should close with an audible noise.
On intermittent pilot systems a ticking noise should be heard while the ignition module tries to relight the pilot. After 1 minute the module should lockout and the try for ignition end.
If a direct ignition system is employed, the ignitor should glow and an attempt at ignition take place. After unsuccessfully attempting to light the main burners the ignition module should lock out.
Open the manual shutoff valve in the gas supply line. Reset the ignition control system by interrupting, then restoring electrical power to the boiler. A normal ignition sequence should take place.
BOILER CHECKING & ADJUSTMENT
Pilot Adjustment
The pilot burner flame should envelope 3/8 in, 9.5 mm to 1/2 in, 13 mm, of the thermocouple tip or flame sensing probe, depending on the pilot type. If the pilot flame is out of adjustment, remove the cap next to the pilot tube fitting on the gas valve. Turn the pilot adjustment screw clockwise to decrease the flame, counterclockwise to increase it. Figure 18 depicts a constant pilot, but the adjustment dimensions for an intermittent pilot would be the same.
Figure 18: Pilot Location
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| 1" |
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| ±1/16 |
5/16 |
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±1/16 |
| 3/8" - 1/2" |
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| |
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| FLAME |
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| ON PROBE |
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| BURNER |
| PILOT | TUBE |
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| BRACKET |
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Gas Pressure Adjustment
NATURAL GAS: Optimum results are obtained when the boiler is operated at its full input rating, with 3.5 in, 89 mm, WC of manifold pressure. The manifold pressure should not be more that 5% off this value. The gas valve pressure regulator has been preset at the factory. If adjustment is necessary the following steps must be followed:
1.Attach a manometer to the pressure tap on the gas valve body.
2.Remove the regulator adjustment screw cap from the gas valve body.
3.Rotate the regulator adjustment screw clockwise to increase the manifold pressure, counterclockwise to decrease it.
4.Replace the regulator adjustment screw cap and pressure tap plug.
CAUTION: Never force the regulator adjustment screw beyond the stop limits or damage to the gas valve will occur!
PROPANE GAS: A manifold pressure of 10.0 in, 254 mm, WC must be maintained for proper operation of the boiler. If the manifold pressure is off by more than 5% adjust it according to steps 1 through 4 above.
Input Rate
Gas appliances are rated based on sea level operation with no adjustment required at elevations up to 2000 feet. At elevations above 2000 ft, 610 m, input ratings should be reduced by 4% for each 1000 ft, 305 m above sea level. Check the input rate as follows:
1.Turn off all other gas appliances that use the same gas meter as the boiler.
2.Call your gas supplier and ask for the heating value of the gas.
3.Start the boiler and let it run for 15 minutes.
4.Using the gas meter and a stop watch, clock the time that it takes to burn 1 cubic foot of gas. To increase the accuracy of the time, clock the time that it takes to burn 10 cubic feet of gas and divide the time by 10.
5.Insert the heating value and the time, in seconds, into the formula below.
RATE in = HEATING VALUE (BTU/FT3) (3600S/HR)
Time (s/ft3)
EXAMPLE: If: heating value = 1000 BTU/ft3
time/ft3 = 18 s/ft3
RATE in = (1000 BTU/ft3) (3600 s/hr)
18 s/ft3
RATE in = 200,000 BTU/hr
