valve, if applicable, and the temperature limit switch on gas and electric heat units. The unit control 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 computer 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 units are painted with a long lasting, powder paint that stands up over the life of the unit. The paint used has been proven by a 1000 hour salt spray test.
•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 rigging holes 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. Utility connections can be made quickly and with a minimum amount of field labor. All units are shipped with 2" throw-away filters installed.
•Wide Range of Indoor Airflows - All supply air blowers are equipped with a belt drive that can be adjusted to meet the exact requirements of the job. A high static drive option is available for applications with a higher CFM and/ or static pressure requirement.
•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 a 10- year warranty.
Factory Installed Options
YORK® offers several equipment options factory installed, for the ZJ/ZR/ZF Series.
•Single Input Electronic Enthalpy Economizers - Includes a slide-in /plug-in damper assembly with fully modulating spring-return motor actuator capable of introducing up to 100% outdoor air with nominal 1% leakage type dampers.
The enthalpy system contains one sensor that monitors the outdoor air and determines when the air is cool enough and dry enough to provide free cooling.
The rainhood is painted to match the basic unit and must be field-assembled before installing.
•BAS-Ready Economizer - Includes a slide-in / plug-in damper assembly with fully modulating spring-return motor actuator with zero to 95-degree rotation capable of introducing up to 100% outdoor air with nominal 1% leakage type dampers.
Actuator requires 2-10 VDC input from an external source, such as a field-installed or factory-installed BAS controller. BAS-ready actuators have an adjustable auxiliary end-switch for optional power exhaust control.
For units with optional VAV or Simplicity® Intelli- Comfort™ control, a factory-installed, dry bulb sensor determines if outdoor air temperature is low enough to provide free-cooling operation. (Field-installed humidity sensors for either outdoor air or outdoor & return air streams are available for single enthalpy and differential enthalpy configurations, respectively).
The rainhood is painted to match the basic unit and must be field-assembled before installing.
•Power Exhaust - Our economizer options are available with power exhaust. Whenever the outdoor air intake dampers are opened for free cooling, the exhaust fan will be energized to prevent the conditioned space from being over-pressurized during economizer operation.
The exhaust fan, motor and controls are installed and wired at the factory. The rain hood must be assembled and installed in the field.
The power exhaust option can only be used on bottom duct configurations.
•Motorized Outdoor Air Intake Damper - Includes a slide-in /plug-in damper assembly with a 2- position, spring return motor actuator which opens to a pre-set position whenever the supply air blower is operating and will drive fully closed when the blower unit shuts down.
The rain hood is painted to match the basic unit and must be field assembled before installing.
•Barometric Relief Damper - This damper option can be used to relieve internal building air pressure on units with an economizer without power exhaust. This accessory includes a rain hood, a bird screen and a fully assembled damper. With bottom duct connections, the damper should be mounted over the opening in the return air panel. With horizontal ductwork, the accessory should be mounted on the return air duct.
•Phenolic Coated Evaporator And Condenser Coils - Special coating process that utilizes Technicoat 10-1" processes. Coating is applied by total immersion of the complete coil for maximum protection.
•Electric Heaters - wired for single point power supply.
These nickel chromium heater elements are provided with limit and automatic reset capability to prevent operation at excessive temperatures.
•Variable Air Volume (VAV) - A factory-installed variable frequency drive (VFD), mounted in the Blower Access compartment, is used to control the speed of the indoor blower motor in order to maintain a constant static
