246646-YTG-C-0606

Refrigerant Circuit and Refrigerant Safety Components shall include:

A.Independent fixed-orifice or thermally operated expan- sion devices.

B.Solid core filter drier/strainer to eliminate any moisture or foreign matter.

C.Accessible service gage connections on both suction and discharge lines to charge, evacuate, and measure refrigerant pressure during any necessary servicing or troubleshooting, without losing charge.

D.The unit shall have two independent refrigerant circuits, equally split in 50% capacity increments.

Unit Controls:

A.Unit shall be complete with self-contained low-voltage control circuit protected by a resettable circuit breaker on the 24-volt transformer side.

B.Unit shall incorporate a lockout circuit which provides reset capability at the space thermostat or base unit should any of the following standard safety devices trip and shut off compressor:

C.Loss-of-charge/Low-pressure switch.

(1)High-pressure switch.

(2)Freeze-protection thermostat, evaporator coil. If any of the above safety devices trip, an LED (light-emitting diode) indicator shall flash a diagnostic code that indi- cates which safety switch has tripped.

D.Unit shall incorporate “AUTO RESET” compressor over temperature, over current protection.

E.Unit shall operate with conventional thermostat designs and have a low voltage terminal strip for easy hook-up.

F.Unit control board shall have on-board diagnostics and fault code display.

G.Standard controls shall include anti-short cycle and low voltage protection, and permit cooling operation down to 0 ºF.

H.Control board shall monitor each refrigerant safety switch independently.

I.Control board shall retain last 5 fault codes in non-vola- tile memory, which will not be lost in the event of a power loss.

GAS HEATING SECTION (IF EQUIPPED)

Heat exchanger and exhaust system shall be constructed of aluminized steel and shall be designed with induced draft combustion with post purge logic, energy saving direct spark ignition, and redundant main gas valve. The heat exchanger shall be of the tubular type, constructed of T1-40 aluminized steel for corrosion resistance and allowing minimum mixed air entering temperature of 40 ºF. Burners shall be of the in-

shot type, constructed of aluminum-coated steel. All gas pip- ing shall enter the unit cabinet at a single location, through either the side or bottom, without any field modifications. An integrated control board shall provide timed control of evapo- rator fan functioning and burner ignition. Heating section shall be provided with the following minimum protection:

A.Primary and auxiliary high-temperature limit switches.

B.Induced draft pressure sensor.

C.Flame roll out switch (manual reset).

D.Flame proving controls. Unit shall have two independent stages of capacity (60% 1st stage, 100% 2nd stage).

ELECTRIC HEATING SECTION (IF EQUIPPED)

An electric heating section, with nickel chromium elements, shall be provided in a range of 9 thru 54 KW, offering two states of capacity all sizes. The heating section shall have a primary limit control(s) (automatic reset) to prevent the heat- ing element system from operating at an excessive tempera- ture. The Heating Section assembly shall slide out of the unit for easy maintenance and service. Units with Electric Heating Sections shall be wired for a single point power supply with branch circuit fusing (where required).

UNIT OPERATING CHARACTERISTICS

Unit shall be capable of starting and running at 125 ºF out- door temperature, exceeding maximum load criteria of ARI Standard 340/360. The compressor, with standard controls, shall be capable of operation down to 0 ºF outdoor tempera- ture. Unit shall be provided with fan time delay to prevent cold air delivery before heat exchanger warms up. (Gas heat only)

ELECTRICAL REQUIREMENTS - All unit power wiring shall enter unit cabinet at a single factory provided location and be capable of side or bottom entry to minimize roof penetrations and avoid unit field modifications. Separate side and bottom openings shall be provided for the control wiring.

STANDARD LIMITED WARRANTIES - Compressor – 5 Years, Heat Exchanger – 10 Years, Elect. Heat Elem. – 5 Years, Parts – 1 Year

FACTORY INSTALLED OPTIONAL OUTDOOR AIR (Shall be made available by either/or):

1.ELECTRONIC ENTHALPY AUTOMATIC ECONO- MIZER – Outdoor and return air dampers that are inter- locked and positioned by a fully-modulating, spring- return damper actuator. The maximum leakage rate for the outdoor air intake dampers shall not exceed 2% when dampers are fully closed and operating against a pressure differential of 0.5 IWG. A unit-mounted potenti- ometer shall be provided to adjust the outdoor and return air damper assembly to take in outdoor air to meet the minimum ventilation requirement of the conditioned space during normal operation. During economizer oper- ation, a mixed-air temperature control shall modulate the

Unitary Products Group

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York 102, 90, DH 078 GAS Heating Section if Equipped, Electric Heating Section if Equipped, Unit Operating Characteristics

102, 90, DH 078 specifications

York DH series chillers, specifically models 078, 90, and 102, are recognized in the HVAC industry for their advanced features, efficiency, and reliability. These chillers are designed to provide exceptional cooling performance for commercial and industrial applications, prioritizing energy efficiency and sustainability.

One of the standout features of the York DH series is its dual-compressor system. This design not only enhances reliability but also contributes to energy savings by allowing the unit to operate at varying loads more effectively. This adaptability ensures that the chillers can maintain optimal performance even during fluctuating demand, reducing energy consumption and associated costs.

The DH series chillers employ a microchannel condenser technology that maximizes heat exchange efficiency. This technology reduces the amount of refrigerant required while also minimizing the footprint of the unit, offering significant advantages in space-constrained environments. Additionally, microchannel coils are less susceptible to corrosion, enhancing the longevity and reliability of the chillers.

Another notable feature is the use of variable-speed drives (VSD) in the compressor system. These drives allow for precise control of the compressor speed, enabling the chillers to adjust to the cooling demands dynamically. This flexibility not only enhances the overall efficiency of the system but also contributes to quieter operation, making the chillers suitable for environments where noise levels are a concern.

York's DH series also integrates advanced controls and monitoring capabilities. The intuitive control system allows for easy programming and operation, providing users with real-time data on system performance and diagnostics. This feature aids in maintenance and troubleshooting, reducing downtime and ensuring that the chillers operate at peak efficiency.

Safety is paramount in the design of the York DH chillers. Each model is equipped with multiple safety features, including pressure relief valves and temperature monitoring systems, to protect the unit during operation. This commitment to safety not only safeguards the equipment but also ensures compliance with industry standards.

In conclusion, the York DH 078, 90, and 102 chillers exemplify modern HVAC technology with their dual-compressor systems, microchannel condenser technology, variable-speed drives, and advanced control systems. These features combine to deliver efficient, reliable, and sustainable cooling solutions for a wide variety of applications. The York DH series represents a significant advancement in chiller design and functionality, making it a preferred choice for many professionals in the field.