York DNH018 Installation Manual

Also see for CHAMPION PLUS DNH018: Technical guide

York DNH018 Installation Manual Manual pdf 17 page image

66324-YIM-B-1004Unitary Products Group 17HOT SURFACE PILOT INSTRUCTIONSTo check, adjust or remove the hot surface pilot assembly,CLOSE THE MAIN MANUAL SHUT-OFF VALVE AND SHUTOFF ALL POWER TO THE UNIT.The pilot flame should envelope 1/2 inch of the end of theflame sensor and not contain any yellow color, see Figure 7.To adjust the pilot flame:1. Remove the pilot adjustment cover screw.2. Adjust the pilot adjustment screw to achieve the properpilot flame.3. Replace the pilot adjustment cover screw after the pilotflame is set.To remove the hot surface pilot assembly:1. Disconnect the wiring from the gas valve to the hot sur-face pilot assembly.2. Remove the two (2) #8 screws holding the hot surfacepilot assembly in place.3. Remove the hot surface pilot assembly.To remove the hot surface ignitor and flame sensor assem-bly:1. Remove the clip attaching the ignitor and sensor assem-bly as shown in Figure 8.2. Lift the pilot and sensor from the assembly. Care must betaken not to damage the pilot or sensor when removingthis assembly.ADJUSTMENT OF TEMPERATURE RISEThe temperature rise (or temperature difference between thereturn air and the heated air from the furnace) must lie withinthe range shown on the rating plate and the data in Tables 3and 4.After the temperature rise has been determined, the CFM canbe calculated as follows:After about 20 minutes of operation, determine the furnacetemperature rise. Take readings of both the return air and theheated air in the ducts about six feet from the furnace wherethey will not be affected by radiant heat. Increase the blowerCFM to decrease the temperature rise; decrease the blowerCFM to increase the rise.DIRECT DRIVE BLOWERAll units have direct drive multi-speed blower motors. Refer tothe unit wiring diagram and connect the blower motor for thedesired CFM.CHECKING GAS INPUTNATURAL GAS1. Turn off all other gas appliances connected to the gasmeter.2. With the furnace turned on, measure the time needed forone revolution of the hand on the smallest dial on themeter. A typical gas meter usually has a 1/2 or a 1 cubicfoot test dial.3. Using the number of seconds for each revolution and thesize of the test dial increment, find the cubic feet of gasconsumed per hour from Table 9.If the actual input is not within 5% of the furnace rating withallowance being made for the permissible range of the regu-lator setting, replace the orifice spuds with spuds of theproper size.FIGURE 12 - PROPER FLAME ADJUSTMENTFIGURE 13 - IGNITOR AND FLAME SENSORASSEMBLY3/8Degrees F Temp Rise BTUH Output1.08 CFM×------------------------------------=ORCFM BTUH Output1.08 Degrees F Temp Rise×-------------------------------------------------------------------------=