York P*UR 40 Installation Instructions Manual

Contents

York P*UR 40 Installation Instructions Manual Manual pdf 36 page image

650.75-N4U 035-14370-00036 Unitary Products Groupvided. When reinstalling the filter(s) be sure it completelycovers the plenum opening.To reinstall the filters, simply reverse this procedure.Horizontal ApplicationsIn most horizontal applications the filter is located in thereturn air duct near the furnace or in a filter grille.LubricationBlower motors in these furnaces are permanently lubricatedand do not require periodic oiling.Blower CareEven with good filters properly in place, blower wheels andmotors will become dust laden after long months of opera-tion. The entire blower assembly should be inspected annu-ally. If the motor and wheel are heavily coated with dust, theycan be brushed and cleaned with a vacuum cleaner.The procedure for removing the direct drive blower assemblyfor cleaning is as follows:1. Disconnect the electrical supply to the furnace andremove remove the access doors.2. On downflow/horizontal models only, remove the twowires leading to the auxiliary limit mounted on the sideopposite the blower motor.3. On downflow/horizontal models only, remove four toppanel screws and lift the top panel enough to disengageand remove the flue chase assembly.4. Remove blower assembly mounting screws and slide theblower assembly out of the slots in the deck. If the twoshipping screws were not previously removed, alsoremove and discard these two screws located on eachfront corner of the blower assembly.5. On downflow models only, note the wire/terminal locationand then remove the blower wiring from the furnace con-trol. Remove the protective boot and disconnect runcapacitor wires. Remove the screws securing the electri-cal panel to the blower housing. Pull blower assemblyout of the unit. When cleaning or servicing the blowerassembly, DO NOT remove or change the balance clipson the blower wheel.6. To reassemble, reverse the procedure, restore power tothe furnace and verify operation.Burner Removal/CleaningThe main burners should be checked periodically for dirtaccumulation.If cleaning is required, follow this procedure:1. Turn off the electrical power to the unit.2. Turn off the gas supply at the external manual shutoffvalve and loosen the ground union joint.3. Remove the upper access panel and remove the burnerbox cover.4. Remove the screws that hold the burner box assembly tothe vest panel and remove the assembly.5. Remove burners from the burner assembly.6. Burners may be cleaned by rinsing in hot water.7. Reassemble the burners in the reverse order.Cleaning the Heat Exchanger1. Turn off the main manual gas valve external to the fur-nace.2. Turn off electrical power to the furnace.3. Remove the upper access panel and remove the burnerbox cover.4. Disconnect wires from flame sensor, rollout switch andHSI igniter. Remove igniter carefully, as it is easily bro-ken.5. Remove the screws that hold the burner box assembly tothe vestibule panel and remove the assembly. The upperportion of the heat exchanger will now be exposed.6. Remove the upper cover plate at the top of the furnace.Remove the internal baffle.7. The upper portion of the heat exchanger is nowexposed.8. With a long flexible wire brush, clean inside each tube atboth the top and bottom. The brush must pass aroundthe rear heat exchanger tubes. Vacuum loose scale anddirt from each tube.When replacing filters, DO NOT use a type withexcessively high pressure drop. Some high effi-ciency filters available will cause the furnace tooperate improperly and could result in a safetyhazard.Label all wires prior to disconnection when servic-ing controls. Wiring errors can cause improper anddangerous operation. Verify proper operation afterservicing.