Évaluations - 4, GPA: 3.8
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Facilité d'utilisation
AIR FOR COMBUSTION: Note 3.All hanging hardware and wood is not included with the unit (to be field supplied). 2.Refer to Table 1. Match “Pipe Run in Feet” with appropriate “Gas Input - Cu Ft/Hr” figure. This figure can then be matched to the pipe size at the end of the column. 2.Check gas supply pressure. Each unit heater must be connected to a manifold pressure and a gas supply capable of supplying its full rated capacity (refer to Table 4). A field LP tank regulator must be used to limit the supply pressure to maximum of 14 in. W.C. (3.5 kPa). All piping should be sized in accordance with the latest edition of ANSI Standard Z223.1, National Fuel Gas Code; in Canada, according to CGA-B149. See Tables 1 and 3 for correct gas supply piping size. If gas pressure is excessive on natural gas applications, install a pressure regulating valve in the line upstream from the main shutoff valve. 3.Adequately support the piping to prevent strain on the gas manifold and controls. 4.To prevent the mixing of moisture with gas, run the take-off piping from the top, or side, of the main. 5.5.Standard gas duct furnaces, optional two-stage unitsare supplied with a combination valve which includes: 6.A 1/8 in. N.P.T. plugged tapping, accessible for test gauge connection, must be installed immediately upstream of the gas supply connection to the appliance 7.Provide a drip leg in the gas piping near the gas unit heater. A ground joint union and a manual gas shutoff valve should be installed ahead of the unit heater controls to permit servicing. The manual main shutoff valve must be located external to the jacket. See Figure 1, Pipe installation standard controls. 8.Make certain that all connections have been adequately doped and tightened. 2.Hot areas - Areas where the sun's rays, radiation, or warm air currents may affect control operation. 3.Dead areas - Areas where air cannot circulate freely, such as behind doors or in corners. 2.The power venter motor is energized by the room thermostat on a call for heat. The pressure switch measures the flow through the vent system and energizes the indirect spark ignition system when the flow is correct. 3.The indirect spark ignition system consists of an ignition control module, a dual combination valve, and a spark-ignited pilot burner. When the pressure switch closes, the pilot valves opens and a spark is generated to light the pilot burner. When flame sensing circuit senses that the pilot flame is established, the main gas valve is opened to supply gas to the main burners. When the thermostat is satisfied, the vent system is deenergized and both valves are closed to stop all flow of gas to the unit. 4.The limit switch interrupts the flow of electric current to the main gas valve in case the heater becomes overheated. 5.The fan switch delays the operation of the fan until the heater is warmed, then keeps the fan running after the gas has been turned off until the useful heat has been removed. The startup fan delay must not exceed 90 seconds from a cold start. 6.The wall thermostat (supplied optionally) is a temperature sensitive switch which operates the vent system and the ignition system to control the temperature of the space being heated. It must be mounted on a vibration free, vertical surface away from air currents, in accordance with the instructions furnished with the thermostat (also refer to Electrical Section). 1.Turn off all gas appliances that use gas through the same meter as the unit heater. 2.Turn gas on to the unit heater. 3.Clock the time in seconds required to burn one cubic foot of gas by checking the gas meter. 4.Insert the time required to burn one cubic foot of gas into the following formula and compute the input rate. 2.PROPANE GAS: An exact manifold pressure of 10.0 inches W.C. (2.5 kPa)must be maintained for proper operation of the unit heater. If the unit is equipped with a pressure regulator on the combination gas valve, follow steps “a” through “d” above. If the unit is not so equipped, the propane gas supply system pressure must be regulated to attain this manifold operating pressure. 3.The adjusted manifold pressure should not vary more than 10% from the pressure specified in the Main burner orifice schedule table. 1.Remove the pilot adjustment cap. 2.Adjust the pilot screw to provide a properly sized flame. 3.A proper pilot flame is a soft steady flame that envelops 3/8 to 1/2-inch (9.5 to 12.7 mm) of the flame sensor. 4.Replace the pilot adjustment cap. 2.Turn off the manual gas valve and electrical power to the gas unit heater. 3.To clean or replace the main burners, remove the bottom panel and compress the spring by moving the burner toward the manifold. Slide the opposite end of the burner downward from the locating slot while retaining spring is still compressed. Pull the burners away from the heat. 4.With the burners removed, wire brush the inside surfaces of the heat exchanger. 5.Remove any dirt, dust, or other foreign matter from the burners u...