2525 W CASINO RD BASE FILE 2025-01-03

operation Lack of primary air will cause soft yellow-tipped flames. 2. Start the heater and determine the number of seconds Excess primary air produces short, well-defined flames with a tendency to lift off the burner ports.Proper operation it takes to consume 1 cu.ft.of gas.Two basic formulas with natural gas provides a soft blue flame with a well- are useful: defined inner cone. F1 =3600 C/T ' To increase primary air, loosen the manifold mounting F2=F1/C where screws and tap the manifold away from the mixer tubes h. until yellow-tipped flames disappear. See Figure 14, To F1 =input to heater. cu. ft decrease primary air move the manifold closer to the C =input i heater, cu. s, per pe mixer tubes until flames no longer lift from burner ports, T =calorific value of gas, Btu per sift: but being careful not to cause yellow tipping. Retighten T =time to consume 1 cu. ft: of gas in sec. mounting screws after adjustment. The calorific value of gas may be determined from the local utility or gas dealer. PROPANE GAS FLAME CONTROL These are representative values: Adjustable primary air shutters are attached to the orifices GAS Btu per cu. ft. on the gas manifold for units equipped for propane gas P operation.See Figure 15.An optimum flame will show a slight Natural 1000- 1150 yellow tip. Prior to flame adjustment,operate unit heater with Propane 2500 casing bottom closed for at least fifteen minutes.Then lower 3 hinged bottom and adjust primary air shutters. Loosen wing . If the seconds for 1 cu. ft. are more (input less) than screws and push shutters forward to reduce primary air until shown on Table 4 for model being tested, remove the yellowflame tips appear-Then increase primary air until yellow cap from the pressure regulator and take one clock- tips diminish and a clean blue flame with a well-defined inner wise turn at a time on the adjustment screw until the cone appears.It may also be necessary to adjust the manifold correct time is obtained. If the seconds are less(input position to obtain proper flame.Follow the instructions under greater) than indicated in the table follow the same "Natural Gas Flame Control"for adjusting the manifold. procedure in a counter-clockwise direction.Never remove adjustment screw from regulator. If the correct number of seconds cannot be obtained with- out exceeding the limitations given above,then re-orificing checking input is necessary. Correct orifices can be obtained from Modine rate Manufacturing Company, Racine, Wisconsin. When requesting orifices, state type of gas, Btu content, and CAUTION its specific gravity.Also give model number of unit heater. For example, if the input to the heater is 100,000 Btuh Check the gas supply pressure at the unit upstream from and the calorific value of gas is 1000 Btu per cu.ft., then, f the pressure regulator. For the purpose of input by the second formula, the input is 100 cu. ft. per hr. ; adjustment, the minimum supply pressure should be 6" Table 3 indicates the time for one revolution of various W.C. on natural gas or 11" W.C. on propane. The size meter dials with various input rates.If a 1 cu.ft.meter maximum inlet pressure on natural gas should be 7"W.C. dial is used, we proceed down the cu. ft. column to 100 and 14" W.C. on propane. The pilot flame must be cu. ft. per hr.and then horizontally to the left to determine adjusted as described on page 7. Supply pressure with any gas must never exceed 14" W.C.; if so, install an a time of 36 seconds for one revolution of the dial. See additional pressure regulator upstream of the Table 3 similarly, if the 1/2 cu. ft. dial is used, we deter- combination gas valve. Purging of air from gas lines, mine a time of 18 seconds for one revolution at the piping, and lighting the pilot should be performed as required input. described in ANSI Z223.1-Latest Edition "National Fuel Gas Code"(CAN/CGA-B149 in Canada). Important— Supply pressure and manifold pressure must be checked with unit in operation when making final (g) Pressure Method. adjustments. The pressure method determines input by measuring the INPUT ADJUSTMENTS pressure of the gas in the manifold in inches of water. Gas pressure regulators are adjusted at the factory for 1. Determine orifice size from Table 4 and check actual average gas conditions. It is important that gas be orifice size(s) in unit. supplied to the heater in accordance with the input rating 2. Close manual gas valve. stamped on the serial plate. Actual input should be 3. Remove the 1/8" pipe plug in automatic valve and checked and necessary adjustments made after the attach water manometer or "U" tube which is at least heater is installed. Over-firing, a result of too high an 12" high. input, reduces the life of the unit, increases maintenance, and lowers efficiency. Under no circumstances should 4. Open manual valve and start unit. the input exceed that shown on the rating plate. 5. If pressure as indicated by "U" tube is not more than Input can be determined by the meter-timing method 1/2" higher or lower than indicated in Table 4,adjust provided other gas equipment connected to the meter is regulator as described under"Meter-Timing Method," inoperative during the test . . . or by checking manifold Step 3 above. pressure. If pressure as indicated by "U" tube is more than 1/2 inch higher or lower than indicated in Table 4, check (A) Meter Timing Method main line gas pressure at unit. Adjust main gas regu- lator to supply 6 to 7 inch W.C. pressure to unit regu- 1. Shut off all other gas-burning equipment, including lator on natural gas and 1 V-14"W.C. on propane gas. other pilot lights served by the gas meter. Page 10