DOE-2 Reference Manual Version 2.1 - DOE2.com

v. Packaged Terminal Air Conditioner (PTAC)Packaged Terminal Air Conditioners (PTAC) are designed primarily forcommercial installations to provide the total heating and cooling function fora room or zone, and are specifically designed for through-the-wall installation.The units (which are hybrid systems/plants) are mostly used in hoteland motel guest rooms, apartments, hospitals, nursing homes, and officebuildings (Ref. 10). All PTAC units discharge air directly into the spacewithout ductwork.PTAC with OXCooling and Electric Resistance Heating:This particular PTAC unit provides cooling by the direct expansion of arefrigerant and heating by an electric resistance heater. In its most basicconfiguration this PTAC consists of a compressor, an air-cooled condenser witha fan discharging heat to the outdoors, an evaporator usually with a two-speedfan supplying cooled air to the indoors, an electric heater, a filter (notshown), and a thermostat. The unit may be specified with outside ventilationair. This PTAC unit has no return fan option and the supply fan is assumed tobe a blowthrough fan with the fan motor located inside the airstream.Optionally, the unit may be specified with a thermostat with night setback.A number of optional features and control strategies can be specified forthis system. The optional features are discussed in Table IV.2 and thesection entitled, "Explanation of System Options" (immediately following TableIV.2). The possible control strategies for this system are discussed in Sec.B.5 of this chapter. It is highly recommended that the user read that portionof Sec. B.5 that is applicable to this system.Table IV.24 shows the commands and keywords that must be entered forsimulation of this system, as well as those that are applicable qut optional(i.e., program uses default value if entry is omitted). To specify this typeof PTAC, specify HEAT-SOURCE ~ ELECTRIC.SUPPLYAIR ,"',,>0--"---,----,'#NHEATING~-l'ILRETURNA