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Trane PKG-PRC002-EN Occupied ZoneTemperature Control, Heating Electric, Supply Air Tempering

Models: PKG-PRC002-EN

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Sequence of

Controls Operation

Zone Temperature Control Unit Sequence Of Operation

1

Occupied ZoneTemperature Control

Cooling/Waterside Economizer During occupied cooling mode, the waterside economizer option and mechanical cooling function to control zone temperature. If the entering condenser water temperature is appropriate to use “free cooling,” the economizer initiates to attempt to satisfy the cooling zone temperature setpoint with the compressors staging on as necessary. Minimum on/off timing of compressors prevents rapid cycling.

Waterside economizing enables when the unit’s entering water temperature is below the unit’s entering mixed air temperature by 4 F plus the user adjustable economizer approach temperature. The approach temperature default is 4 F and is adjustable from 0-9 F at the human interface (HI) panel. Waterside economizing disables when the unit’s entering water temperature is not below the unit’s entering mixed air temperature by at least the water economizer approach temperature. The approach temperature defaults to 4 F and is adjustable from 0-9 F at the HI. The economizer acts as the first stage of cooling. If the economizer is unable to maintain the zone temperature setpoint, the compressor module will bring on compressors as required to meet the setpoint.

If the unit does not include an economizer, only mechanical cooling will operate to satisfy cooling requirements.

Cooling/Airside Economizer During occupied cooling mode, the economizer option and mechanical cooling operate to control zone temperature. If the outside air enthalpy is appropriate for airside economizing or “free cooling,” the economizer initiates to satisfy the cooling zone temperature setpoint with the compressors staging on as necessary. Minimum on/off timing of compressors will prevent rapid cycling.

On units with an airside economizer, a call for cooling will modulate the fresh air

dampers open. The rate of economizer modulation is based on deviation of the zone temperature from setpoint; i.e., the further away from setpoint, the faster the fresh air damper will open. First stage of cooling will start after the economizer reaches full open.

Note that the airside economizer will only function freely if ambient conditions are below the enthalpy control settings or below the return air enthalpy if unit has comparative enthalpy installed. If outside air is not suitable for “economizing,” the fresh air dampers drive to the minimum open position. A field adjustable, factory default setting in the human interface panel orTracer® can provide the input to establish the minimum damper position.

At outdoor air conditions above the enthalpy control setting, only mechanical cooling is used and the fresh air dampers remain at minimum position.

If the unit does not include an airside economizer, only mechanical cooling will operate to satisfy cooling requirements.

Heating: Electric

On units with electric heating, the zone temperature can be controlled to a heating setpoint during the occupied mode by cycling a single stage electric heater. Interface is provided for field supplied single stage electric heat. The zone temperature heating setpoint and deadband are user defined at the human interface panel.

Heating: Hot Water or Steam

On units with hot water or steam heating, the zone temperature can be controlled to a heating setpoint during the occupied mode. The zone temperature heating setpoint and deadband are user defined at the human interface panel.

Supply Air Tempering

For hot water, steam, or electric heat units in the heat mode but not actively heating, if the supply air temperature drops to 10 F (5.5 C) below the occupied zone heating temperature setpoint, one stage of heat will be brought on to maintain a minimum supply air temperature. The unit transitions out of heat mode if the supply air temperature rises to 10 F above the occupied zone heating temperature setpoint.

Auto Changeover

When the system mode is auto, the mode will change to cooling or heating as necessary to satisfy the zone cooling and heating setpoints. The zone cooling and heating setpoints can be as close as 2 F (1.1 C) apart.

2

Unoccupied ZoneTemperature Control

Cooling and Heating

Both cooling and heating modes can be selected to maintain unoccupied zone temperature deadbands. For unoccupied periods, heating, economizer operation, or compressor operation can be selectively locked out at the human interface panel.

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PKG-PRC002-EN

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Trane PKG-PRC002-EN Occupied ZoneTemperature Control, Heating Electric, Heating Hot Water or Steam, Supply Air Tempering
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PKG-PRC002-EN specifications

The Trane PKG-PRC002-EN is a groundbreaking packaged rooftop unit designed to meet the diverse needs of commercial and industrial spaces. This model showcases Trane’s commitment to innovation, energy efficiency, and reliability, making it a preferred choice for HVAC professionals and building owners alike.

One of the main features of the PKG-PRC002-EN is its high-efficiency design. This unit leverages advanced technologies to minimize energy consumption while ensuring optimal cooling and heating performance. Its efficient compressor, coupled with enhanced heat exchangers, significantly reduces operating costs and energy bills, aligning with today’s sustainability goals.

The PKG-PRC002-EN features a robust and durable construction, which translates to enhanced longevity and reduced maintenance requirements. Designed for ease of installation, the unit is compact and lightweight, facilitating seamless retrofitting and integration into existing systems. Furthermore, its accessible service panels allow for straightforward maintenance and repairs, thus minimizing downtime and service disruptions.

Equipped with Trane's advanced control technology, the PKG-PRC002-EN offers precise temperature management, ensuring consistent comfort across different zones within a building. The intuitive controls enable users to program schedules and adjust settings based on their specific needs, enhancing comfort while maximizing efficiency.

The model also incorporates advanced filtration options, improving indoor air quality by effectively reducing pollutants and allergens. This focus on health and safety is essential, especially in commercial settings where air quality can significantly impact occupant well-being and productivity.

Another notable characteristic of the PKG-PRC002-EN is its low noise levels during operation, which is essential for maintaining a conducive indoor environment in workplaces, retail spaces, or educational institutions. The unit's design minimizes sound transmission, creating a more pleasant atmosphere for occupants.

In summary, the Trane PKG-PRC002-EN is a highly efficient, reliable, and user-friendly rooftop unit that combines advanced technology with robust construction. Its energy-saving features, superior air quality options, and focus on quiet performance make it an excellent choice for modern commercial HVAC applications, ultimately contributing to sustainable building practices and enhanced occupant comfort.