Assessments - 4, GPA: 3.8
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2. For vent damper-equipped models, with the thermostat set to call for heat, observe that vent damper position indicator rotates to the open position (see Figure 2.5). Damper must be in the open position when appliance main burner is operating. a. After damper opens, spark should appear at the pilot ignition electrodes. FIGURE 3.1: STEAM CONTROL ARRANGEMENT PRESSURE RELIEF VALVE PRESSURE CONTROL PRESSURE GAUGE GAS VALVE PRESSURE RELIEF VALVE DISCHARGE PIPING b. Set thermostat to no longer call for heat. Spark should stop. Observe that damper position indicator rotates to the closed position. c. Set thermostat to call for heat. 3. Light the boiler. For Model GB200 boilers with intermittent pilot, see lighting instruction on Page 14. 4. Observe pilot and main burner flame (see Figure 3.2). All burner ports should be ignited and burn with a steady blue flame. CAUTION: Never leave the job with yellow burning flames. This condition indicated poor combustion and will quickly carbonize the boiler, reducing efficiency and boiler life. It may also be an indication of improper venting or combustion air supply. If unable to adjust flame properly, consult your local utility. 5. Boilers are shipped from the factory with the primary air shutters on the main burner wide open. It is recommended these air shutters be left in the wide open position unless there is lifting of the flame above the burner ports. If there is lifting, the air shutters should be gradually closed until the lifting is eliminated. It may also be necessary to adjust the primary air shutters if the input rate is reduced by a change in the orifices. 6. After burner has been in operation for about 10 minutes, check gas input rate to boiler as follows: a. Make sure all appliances served by the meter are turned off during timing of gas input rate to the boiler. b. Measure the time in seconds that it takes for the boiler to use 10 cubic feet of gas. Divide 36,000 by the number of seconds (this is the number of cubic feet of gas used per hour). Multiply this figure by the heating value of the gas to obtain Btu input per hour. 11 FIGURE 3.2: BURNER FLAME COMPARISON/PILOT FLAME YELLOW FLAME (TOO LITTLE AIR) YELLOW TIPPING (MARGINAL) LIFTING (TOO MUCH AIR) NORMAL (HARD FLAME) NORMAL PILOT FLAME MAIN BURNER FLAMES Q314A/Q309A CONSTANT PILOT MODELS Q3451B INTERMITTENT IGNITION PILOT MODELS Example: A GB200-4L boiler takes 5 minutes, 27 seconds to use 10 cubic feet of natural gas. The local utility indicated the heating value of the natural gas being supplied is 1000 Btu/cu ft. Therefore: 5 minutes, 27 seconds = 327 seconds. 36,000 x 1000 = 110,000 Btu/hr 327 Therefore, the boiler input is correct. NOTE: Before calculating the input of the heating equipment, obtain the heating value of the gas from the local utility. 7. If input needs to be corrected, adjust combination gas valve pressure regulator. (Regulator is factory set at 31/ 2" W.C. for natural gas and 10" W.C. for propane.) Turn adjusting screw clockwise to increase gas flow (increase input). Turn adjusting screw counterclockwise to decrease gas flow (decrease input). In no case should final manifold pressure setting vary more than + .3" from factory-set pressures. If rated input cannot be obtained with adjustment, gas supply pressure or orifice size may be cause. Consult local utility and Smith. 8. Gas burner orifices supplied with boiler have been carefully designed to provide correct gas input rate for most gas conditions typically found in the U.S. Occasionally, however, local gas characteristics may not allow unit to be properly adjusted for input. If this is the case, local utility or Smith may recommend orifices be changed. When changing orifices follow the procedures detailed in Section 4 of this manual. 9. Start and stop burners several times by raising and lowering the thermostat setting. 10. After boiler has been firing long enough to raise boiler pressure above minimum setting of the primary pressuretol limit, check limit by turning its setting from maximum to minimum setting. This should turn boiler off. Return limit to desired setting. 11. Check boiler safety shutoff controls. For boilers with intermittent pilot, with boiler firing, disconnect wire connected to the "PV" terminal on the Honey- well S8600 control. The gas valve should close. For boilers with constant pilot, with boiler firing, turn the gas control knob on the gas valve to “PILOT”. The burners should go out. Extinguish the pilot and wait 3 minutes. Turn the gas valve control knob to “ON”. There should be NO gas flow to the main burners with the pilot out! If gas flow is detected, immediately turn the gas valve control knob to “OFF” and have the problem corrected. 12. On initial start-up and prior to each heating season, boiler must be cleaned with a commercially available steam boiler cleaner (see "Steam Boiler Cleaning Instructions" in Section 4 of this manual). 12 WARNING: If you do not follow these instructions exactly, a fir...