York DNH018 Installation Manual

Also see for CHAMPION PLUS DNH018: Technical guide

York DNH018 Installation Manual Manual pdf 19 page image

66324-YIM-B-1004Unitary Products Group 19BURNERAt the beginning of each heating season, make a visualcheck of the main burner flame. If it is not possible to adjustfor the proper flame, the burners may need cleaning.TO CLEAN BURNERSRemove them from the furnace as explained in BurnerInstructions. Clean burners with hot water applied along topof the burner.COMBUSTION AIR DISCHARGEVisually inspect discharge outlet periodically to insure sootand dirt buildup is not excessive. If necessary, clean to main-tain adequate combustion air discharge.The manufacture recommends that the furnace system beinspected once a year by a qualified service person.CLEANING FLUE PASSAGES AND HEATING ELE-MENTSWith proper combustion adjustment the heating element of agas fired furnace will seldom need cleaning. If the elementshould become sooted, it can be cleaned as follows:1. Remove the burner assembly as outlined in BURNERINSTRUCTIONS.2. Remove the screws securing the restrictor plate to thetube sheet.3. Using a wire brush on a flexible wand, brush out theinside of each heat exchanger from the burner inlet andflue outlet ends.4. Brush out the inside of the restrictor plate to the tubesheet.5. If soot build-up is particularly bad, remove the vent motorand clean the wheel and housing.6. After brushing is complete, blow all brushed areas withair or nitrogen. Vacuum as needed.7. Replace parts in the order they were removed in steps 1through 3.CHECKING SUPPLY AIR CFMTo check the supply air CFM after the initial balancinghas been completed:1. Remove the two ¼ inch dot plugs in the duct panel.2. Insert at least 8 inches of ¼ inch tubing into each ofthese holes for sufficient penetration into the airflow onboth sides of the indoor coil.3. Using an inclined manometer, determine the pressuredrop across the dry evaporator coil. Since the moistureon an evaporator coil may vary greatly, measuring thepressure drop across a wet coil under field conditionswould be inaccurate. To ensure a dry coil, the compres-sors should be deactivated while the test is being run.4. Knowing the pressure drop across a dry coil, the actualCFM through the unit can be determined from the curvein Coil Delta P vs. Supply Air CFM figure.After readings have been obtained, remove the tubesand reinstall the two ¼ inch plugs removed in Step 1.De-energize the compressors before taking any testmeasurements to ensure a dry indoor coil.Failure to properly adjust the total system air quan-tity can result in extensive system damage.