York DM090 Installation Manual

Also see for PREDATOR DM 090: Installation manual Technical guide Installation manual Technical guide Installation instruction

Contents

127408-YIM-B-0606Unitary Products Group 23LP UNITS, TANKS AND PIPINGAll gas heat units are shipped from the factory equipped fornatural gas use only. The unit may be converted in the fieldfor use with LP gas with accessory kit model number1NP0441.All LP gas equipment must conform to the safety standards ofthe National Fire Protection Association.For satisfactory operation, LP gas pressure must be 10.5inch W.C. at the unit under full load. Maintaining proper gaspressure depends on three main factors:1. The vaporization rate which depends on the temperatureof the liquid and the “wetted surface” area of the con-tainer(s).2. The proper pressure regulation. (Two-stage regulation isrecommended).3. The pressure drop in the lines between regulators andbetween the second stage regulator and the appliance.Pipe size required will depend on the length of the piperun and the total load of all appliances.Complete information regarding tank sizing for vaporization,recommended regulator settings, and pipe sizing is availablefrom most regulator manufacturers and LP gas suppliers.LP gas is an excellent solvent and will quickly dissolve whitelead and most standard commercial compounds. A specialpipe dope must be used when assembling wrought iron orsteel pipe for LP. Shellac base compounds such as Gaskolacor Stalastic, and compounds such as Rectorseal #5, Clyde’s,or John Crane may be used.Check all connections for leaks when piping is completedusing a soap solution. NEVER USE A FLAME.VENT AND COMBUSTION AIRVenting slots in the heating compartment access panelremove the need for a combustion air hood. The gas heatflue exhaust is routed through factory installed exhaust pipingwith screen. If necessary, a flue exhaust extension may beinstalled at the point of installation.OPTIONS/ACCESSORIESELECTRIC HEATElectric heaters are available as field installed accessories.Refer to electric heat instructions for installation. These heat-ers mount in the heat compartment with the heating elementsextending into the supply air chamber. All electric heaters arefused and intended for use with single point power supply.MOTORIZED OUTDOOR DAMPERThe Motorized Outdoor Damper can be a factory installedoption or a field installed accessory. If factory installed, referto the instructions included with the outdoor air hood to com-plete the assembly. Field installed Motorized OutdoorDamper accessories include complete instructions for instal-lation.ECONOMIZERThe Economizer can be a factory installed option or a fieldinstalled accessory. If factory installed, refer to the instruc-tions included with the outdoor air hood to complete theassembly. Field installed Economizer accessories includecomplete instructions for installation.There are two Economizer options:1. Down Flow application with barometric relief hood stan-dard.2. Horizontal Flow application that requires the purchase ofa barometric relief hood.POWER EXHAUSTThe Power Exhaust can be a factory installed option or a fieldinstalled accessory. If factory installed, refer to the instruc-tions included with the outdoor air hood to complete theassembly. Field installed Power Exhaust accessories includecomplete instructions for installation.The Power Exhaust factory installed option is for Down Flowapplication only.There are two field installed Power Exhaust accessories:1. Down Flow application.2. Horizontal Flow application that requires the purchase ofa barometric relief hood.RAIN HOODAll of the hood components, including the filters, the gasket-ing and the hardware for assembling, are packaged andlocated between the condenser coil section and the main unitFIRE OR EXPLOSION HAZARDFailure to follow the safety warning exactly couldresult in serious injury, death or property damage.Never test for gas leaks with an open flame. Use acommercially available soap solution made specifi-cally for the detection of leaks to check all connec-tions. A fire or explosion may result causing propertydamage, personal injury or loss of life.