York DM 078 manual YTG-C-0708

Models: DM 078

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246645-YTG-C-0708

Balanced Heating – The Predator® offers “Ultimate Heat- ing Comfort” with a balance between 1st and 2nd stage gas heating. The 1st stage of a gas heat Predator® unit provides 60% of the heating capacity. Balanced heating allows the unit to better maintain desired temperatures.

Convertible Airflow Design – The side duct openings are covered when they leave the factory. If a side sup- ply/return is desired, the installer simply removes the two side duct covers from the outside of the unit and installs them over the down shot openings. No panel cutting is required. Convertible airflow design allows maximum field flexibility and minimum inventory.

System Protection - Suction line freezestats are supplied on all units to protect against loss of charge and coil frost- ing when the economizer operates at low outdoor air tem- peratures while the compressors are running. Every unit has solid-core liquid line filter-driers and high and low- pressure switches. Internal compressor protection is stan- dard on all compressors. Crankcase heaters are standard on reciprocating compressors. Scroll compressors do not require crankcase heaters. Phase Monitors are standard on units with scroll compressors. This accessory monitors the incoming power to the unit and protects the unit from phase loss and reversed phase rotation.

Advanced Controls - Simplicity™ control boards have standardized a number of features previously available only as options or by utilizing additional controls.

Low Ambient - An integrated low-ambient control allows all units to operate in the cooling mode down to 0°F outdoor ambient without additional assis- tance. Optionally, the control board can be pro- grammed to lockout the compressors when the outdoor air temperature is low or when free cooling is available.

Anti-Short Cycle Protection - To aid compressor life, an anti-short cycle delay is incorporated into the standard controls. Compressor reliability is further ensured by programmable minimum run times. For testing, the anti-short cycle delay can be temporarily overridden with the push of a button.

Fan Delays - Fan on and fan off delays are fully pro- grammable. Furthermore, the heating and cooling fan delay times are independent of one another. All units are programmed with default values based upon their configuration of cooling and heat.

Safety Monitoring - The control board monitors the high and low-pressure switches, the freezestats, the gas valve, if applicable, and the temperature limit switch on gas and electric heat units. The unit con- trol board will alarm on ignition failures, compressor lockouts and repeated limit switch trips.

Nuisance Trip Protection and Strikes - To prevent nuisance trouble calls, the control board uses a “three times, you’re out” philosophy. The high and low-pressure switches and the freezestats must trip three times within two hours before the unit control board will lock out the associated compressor.

On Board Diagnostics - Each alarm will energize a trouble light on the thermostat, if so equipped, and flash an alarm code on the control board LED. Each high and low-pressure switch alarm as well as each freezestat alarm has its own flash code. The control board saves the five most recent alarms in memory, and these alarms can be reviewed at any time. Alarms and programmed values are retained through the loss of power.

Reliable – From the beginning – All units undergo com- puter automated testing before they leave the factory. Units are tested for refrigerant charge and pressure, unit amperage, and 100% functionality. For the long term – All Predator® units are painted with a long lasting, pow- der paint that stands up over the life of the unit. The paint used has been proven by a 1000 hour salt spray test.

Flexible Placement – All models and configurations share the same cabinet/footprint and thus the same roof curb. You have the flexibility to set one curb and choose the correct tonnage size and heating option after the internal loads have been determined.

To further simplify planning and installation, Predator® cabinets are designed to fit your roof. With the optional roof curb, the unit ductwork is designed to fit around 24” on-center joists or between 48” on-center joists.

The drain pan can be rotated to drain to either the front or the rear of the unit. Additionally, the drain pan can be piped to drain through the roof curb. As it is sometimes difficult to have a level installation, the drain pan features a generous slope to ensure proper drainage.

Full Perimeter Base Rails – The permanently attached base rails provide a solid foundation for the entire unit and protect the unit during shipment. The rails offer fork- lift access from 3 sides, and rigging holes are available so that an overhead crane can be used to place the units on a roof.

Easy Installation – Gas and electric utility knockouts are supplied in the unit underside as well as the side of the unit. A clearly identified location is provided to mount a field supplied electrical disconnect switch. Utility con- nections can be made quickly and with a minimum amount of field labor.

All units are shipped with 2” filters installed.

Wide Range of Indoor Airflows – All indoor fan motors are belt-drive type providing maximum flexibility to han- dle most airflow requirements. For high static applica- tions, factory installed alternate indoor fan motors are available. With the optional indoor fan motor, all units can supply nominal airflow at a minimum of 1.5” ESP.

Warranty - All models include a 1-year limited warranty on the complete unit. Compressors and electric heater elements each carry a 5-year warranty. Aluminized steel and stainless steel tubular heat exchangers carry an additional 10-year warranty.

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Johnson Controls Unitary Products

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York DM 078 manual YTG-C-0708