FIELD-INSTALLED Accessories

FAN SYSTEM - All 2-1/2, 3, 3-1/2 and 4 ton models operate over a wide range of design conditions with a constant CFM, electrically commutated (ECM) fan motor. These units easily match all types of applications and provide greater on site flexibility to match comfort requirement. These models have 2 cooling speeds and a single heating speed. The cooling speed is factory set and can be field adjusted to a second speed. The heating speed is factory set to maintain mid point rise at the units heating input. It cannot be field adjusted. This allows maximum comfort conditions.

Two ton models operate over a wide range of design condi- tions with a 3-speed direct-drive fan motor. These single phase models have the Comfort-Match system that allows different speed taps for heating or cooling operations.

SIMPLE CONTROL CIRCUIT - A low voltage printed circuit board contains a diagnostic indicator light and a low voltage terminal strip. An additional set of pin connectors is also pro- vided to simplify the field interface of external controls. Mate- n-lock plug connectors are used. The electrical control box is not located in the compressor compartment. The controls are mounted on a Control-Tilt control panel to allow the access cover to be removed for trouble shooting and maintenance without affecting the normal system operating pressures. All wiring internal to the unit is color/number coded.

PROTECTED COMPRESSOR - The compressor is internally protected against high pressure and temperature. This is accomplished by the simultaneous operation of high pressure relief valve and a temperature sensor which protect the com- pressor if undesirable operating conditions occur.

EXCLUSIVE COIL DESIGN - Grooved copper tubes and enhanced aluminum fin construction improves heat transfer for maximum efficiency and durability.

HEAT EXCHANGERS - Are corrosion-resistant, aluminized- steel tubular construction to provide long-life, trouble-free operation. The unique blow-through design also assures that condensate does not collect in humid areas when in the cool- ing cycle. This adds to longer heat exchanger life and higher long term efficiencies.

POST PURGE INDUCED DRAFT COMBUSTION - Exhausts combustion products from the heat exchanger upon comple- tion of the heating cycle to prolong the heat exchanger life.

SELF DIAGNOSTIC FAN CONTROL MODULE - Due to this self diagnostic control, less on site time is required to trouble shoot these units.

HOT SURFACE TO PILOT IGNITION - Provides faster heat delivery. This ignition is highly reliable, durable and elimi- nates nuisance lockouts. Also assures starts in damp condi- tions.

MULTI PORT IN-SHOT BURNERS - No field adjustment is required to mix the air and gas. These burners are con- structed of high-grade corrosion-resistant, aluminized-steel.

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LOW MAINTENANCE - Long life, permanently lubricated condenser and evaporator fan motor bearings need no annual maintenance adding greater reliability to the unit. Blower assembly can be easily cleaned by the unique Slip- Track slide-out blower assembly.

SECURED SERVICE ACCESS PORTS - Protected, exter- nally mounted, re-usable service access ports are provided on both the high and low lines for ease of evacuating and charging the system. No final field mounting required.

EASY SERVICE ACCESS - A large, single panel covers the electrical and gas controls makes servicing easy. The blower compartment has an additional large panel with a built-in handle tab. Removing this panel will allow the blower assem- bly to slide-out for easy removal for maintenance and ease of trouble shooting.

REPLACEMENT PARTS - The installer requires no special training to replace any of the components of these units and does not need to maintain an inventory of unique parts.

SYSTEM INTEGRATION - Each unit has the internal ability to integrate an electronic air cleaner or humidifier to work in conjunction with the base unit.

LOW NOx KIT - Kit includes all the necessary hardware and instructions to field convert units to reduce emissions to less than 40 nanogram per Joule. California requirement on single phase models only.

PROPANE CONVERSION KIT - Kit includes burner orifices, gas valve conversion and installation instructions necessary to field convert unit from natural gas to propane.

HIGH ALTITUDE CONVERSION KIT (Natural Gas/Propane)

-Kit includes all necessary labels and instructions to field alter units with natural gas/propane for installations above 2000 feet. Burner orifices must be obtained from Source 1 Parts. Propane Conversion Kit must be obtained separately.

ECONOMIZER DOWN DISCHARGE / SUPPLY KIT - Modu- lating integrated economizer provides simultaneous opera- tion between the mechanical cooling and economizer operation. Independent blade design insures proper control and less than 1% leak rate. Includes hood and mesh bird screen filter integrated into the hood, dry bulb sensor and relief damper. Separate field accessories of single enthalpy and dual enthalpy are also available. A built-in barometric relief of 25% is provided.

SINGLE ENTHALPY SENSOR - Sensor replaces dry bulb sensor standard in economizer kit. Provides improved econo- mizer operation by sensing the dry bulb temperature from outdoors plus the enthalpy content of the outdoor air.

DUAL ENTHALPY SENSOR - Additional sensor to single enthalpy sensor. Sensor senses both the return air tempera- ture dry bulb and humidity in conjunction with the single

4	Unitary Products Group