262292-YTG-B-0107

FIGURE 1: UNIT CUTAWAY

•Electric Heat Operation - All electric heat models (factory installed only) are wired for a single power source and include a bank of nickel chromium elements mounted at the discharge of the supply air blower to provide a high velocity and uniform distribution of air across the heating elements. Every element is fully protected against excessive current and temperature by fuses and two thermal limit switches.

•The power supply wiring can be routed into the control box through a threaded pipe connection in the base pan of the unit or through a knockout in the wiring panel on the front of the unit.

•BAS Controls - York’s Magnum series units offer factory mounted BAS controls such as Novar, Honeywell, Johnson, and CPC.

REHEAT MODE SEQUENCE OF OPERATION

The reheat control board allows the user to select two different modes of operation via a jumper connection on the board. (See Figure 2.) Each mode is described below. Refer to Figures 2 - 4 when reading this section.

LOCATION OF VFD (Optional)

LOCATION OF VFD BYPASS (Optional)

“NORMAL” MODE

When the reheat control board (RCB) detects a need for dehumidification (24VAC) at "HUM" via the field supplied dehumidistat connected to RHTB-1 and RHTB-2 and there is not a call for cooling, it energizes the hot gas relay (HGR), which energizes the 3-way valve (SOL 3), the condenser coil valve (SOL 2), and de-energizes the reheat coil bleed valve (SOL 1). The Y1 signal is passed to the unit control board (UCB), which engages circuit # 1, resulting in circuit #1 reheat mode operation.

When the room thermostat calls for first stage cooling, with or without a call for dehumidification, the RCB senses a signal through "Y1", de-energizing the HGR, which de-energizes SOL 3 and SOL 2, and energizes SOL 1, engaging circuit # 1, resulting in circuit #1 cooling mode operation.

When the room thermostat calls for second stage cooling, the RCB senses a signal through "Y1" & "Y2" and engages circuit #1 and circuit #2 in the cooling mode.

Indoor blower operation is initiated upon a call for first stage cooling, second stage cooling or dehumidification.

Unitary Products Group

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York WR240, WR300 warranty Unit Cutaway, Normal Mode
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WR240, WR300 specifications

The York WR300 and WR240 are advanced water-cooled screw chillers that embody innovation, efficiency, and sustainability. These chillers are part of York’s renowned product line and are designed for a variety of commercial applications, ranging from large office buildings to industrial processes.

One of the standout features of the WR300 and WR240 models is their energy efficiency. Both units utilize the latest in variable-speed drive technology, which allows for precise control of the compressor speed based on the cooling demand. This results in lower energy consumption, especially in part-load conditions, making the chillers not only eco-friendly but also cost-effective over their lifespan.

The WR300 is designed to provide cooling capacities of up to 300 tons, while the WR240 offers capacities of up to 240 tons. These substantial capacities make them suitable for larger applications where dependable cooling is essential. The units are compact in design, allowing for flexible installation options, even in properties with space constraints.

Another key characteristic of the York WR chillers is their advanced refrigerant technology. Utilizing R-134a refrigerant, these chillers comply with global environmental standards and regulations, contributing to reduced greenhouse gas emissions. This makes the WR300 and WR240 not only high-performing but also aligned with a sustainable future.

The chillers are equipped with a robust control system that enhances operational performance and reliability. Features such as the advanced York YZ controller facilitate remote monitoring and diagnostics, allowing facility managers to optimize chiller performance and enhance maintenance processes. This advanced control capability minimizes downtime and maximizes productivity.

Noise reduction is also a significant consideration with these units. The WR series incorporates sound-dampening technology, making it an ideal choice for installations in noise-sensitive environments, such as schools or hospitals.

Furthermore, the construction of these chillers emphasizes durability and ease of maintenance. The components are engineered to withstand harsh operating conditions, and the design allows for straightforward access to key components, thereby simplifying service tasks.

In summary, the York WR300 and WR240 chillers stand out due to their energy efficiency, advanced refrigerant technology, robust control systems, and durability. These features make them ideal solutions for modern HVAC needs, supporting businesses while prioritizing environmental stewardship.
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