York DHG180 Installation Instruction

Also see for SUNLINE DHG 180: Installation instruction

York DHG180 Installation Instruction Manual pdf 22 page image

035-17233-000-C-070222 Unitary Products5. Set room thermostat to desired temperature.(If thermo-stat set temperature is above room temperature, pilotburner ignition will occur and, after an interval to provepilot flame, main burners will ignite).TO SHUT DOWN:1. Turn off electric power to unit.2. Depress knob of gas valve while turning to off position.POST-START CHECK LIST (GAS)After the entire control circuit has been energized and theheating section is operating, make the following checks:1. Check for gas leaks in the unit piping as well as the sup-ply piping.2. Check for correct manifold gas pressures. See CheckingGas Input.3. Check the supply gas pressure. It must be within the lim-its shown on rating nameplate. Supply pressure shouldbe checked with all gas appliances in the building at fullfire. At no time should the standby gas line pressureexceed 13", nor the operating pressure drop below 5.0"for natural gas units. If gas pressure is outside these lim-its, contact the local gas utility for corrective action.MANIFOLD GAS PRESSURE ADJUSTMENTSmall adjustments to the high-fire gas flow may be made byturning the pressure regulator adjusting screw on the auto-matic gas valve. Refer to Figure 16.Adjust as follows:1. Remove the cap on the regulator. It's located next to thepush-on electrical terminals.2. To decrease the gas pressure, turn the adjusting screwcounterclockwise.3. To increase the gas pressure, turn the adjusting screwclockwise.NOTE: The correct manifold pressure for these furnaces is3.5 IWG 0.3.PILOT CHECKOUTThe pilot flame should envelope the end of the flame sensor.Refer to Figure 16. To adjust pilot flame, (1) remove pilotadjustment cover screw, (2) increase or decrease the clear-ance for air to the desired level, (3) be sure to replace coverscrew after adjustment to prevent possible gas leakage.Put the system into operation and observe through completecycle to be sure all controls function properly.BURNER INSTRUCTIONSTo check or change burners, pilot or orifices, CLOSE MAINMANUAL SHUT-OFF VALVE AND SHUT OFF ALL ELEC-TRIC POWER TO THE UNIT.1. Remove the screws holding either end of the manifold tothe burner supports.2. Open the union fitting in the gas supply line justupstream of the unit gas valve and downstream from themain manual shut-off valve.3. Remove the gas piping closure panel.4. Disconnect wiring to the gas valves and spark ignitors.Remove the manifold-burner gas valve assembly by lift-ing up and pulling back.Burners are now accessible for service.FIGURE 16 : TYPICAL GAS VALVEFIGURE 17 : PROPER FLAME ADJUSTMENT1/8"GAPBETWEENCARRY-OVERTUBEANDFLAMESENSORBULBCARRY-OVERTUBEFLAMESENSORBULBBURNERASSEMBLYBRACKETOn-Off ControlPilot Adj.(Under Screw)High Fire Adj.(Under Screw)