PTS staging valves, newly introduced to the market as part of the Danfoss EXO – Extended Oil-Free program, are designed to improve the performance and reliability of both oil and oil-free centrifugal chillers and heat pumps. These valves offer extremely fast operation, within just 5 seconds, to prevent compressor surge and ensure stable system performance during both startup and shutdown. With this breakthrough speed, they bring a new level of functionality to the market, making them an ideal choice for critical applications, used in data centers, hospitals or industrial processes.
The PTS staging valves are engineered to provide surge protection and stabilize compressor operations, ensuring smooth and reliable system performance, even in the most demanding conditions.
The PTS valves are specially designed to prevent compressor surge, a common issue in centrifugal compressors caused by low pressure during startup. By reacting quickly to surge conditions, the PTS valves stabilize compressor pressure, reducing the risk of damage and extending system life. They could also function as load-balancing valves.
During startup, the PTS valves open rapidly within 5 seconds, connecting discharge to suction via the evaporator to release pressure before the discharge check valve opens. This prevents gas recirculation, protects the compressor from internal shock, and results in faster startup times and more efficient system performance.
At shutdown, the PTS valves quickly release pressure to protect compressor bearings and other components, helping to avoid shaft-bearing contact. During normal shutdown, the staging valve opens and the compressor speed slows down, ensuring smooth operation. The capacity of the staging valves meets the most demanding cases of compressor pressure ratio, ensuring system stability.
In the event of a fault or power loss, the discharge valve closes and the fast opening of the staging valve releases compressor pressure.
Durability: Constructed with high quality materials to ensure long term reliability in oil-free applications and minimize maintenance costs.
Wide refrigerant compatibility: Suitable for all common refrigerants, including A2L, enhancing versatility.
Fast and precise response time: Designed to open quickly during startup and close softly, ensuring tight sealing and pressure stability within 5 seconds.
Flexible sizing: Available in multiple sizes with KV values ranging from 18 to 38 to suit a range of system capacities.
Easy integration: Compatible with Danfoss stepper valve drivers, including EKF, EKE 100, and Alsmart® unit controllers.
The PTS valves are specifically optimized for use with Danfoss TGx and TTx Turbocor® compressors, offering enhanced system stability and reliability. Designed for the most demanding compressor pressure ratios, these valves provide performance in challenging conditions, providing a reliable, energy-efficient solution when paired with Turbocor® compressors.
Compared to traditional solenoid valves and standard stepper motor valves, the PTS valves offer several key advantages:
High flow capacity with a single valve: With high KV values, the PTS valves can handle large flows without sacrificing pressure stability.
Fast response: The rapid opening and closing (within 5 seconds) of the PTS valves help reduce the risk of compressor damage, improving overall system reliability.
Superior sealing: Advanced sealing technology ensures tightness, preventing leaks even under high pressure conditions.
Low pressure drop: PTS valves provide a low-pressure bypass, connecting discharge to suction via the evaporator. This helps increase pressure before the discharge check valve opens, preventing gas recirculation and protecting the compressor from pressure shocks.
The PTS valves are available in three models with KV values ranging from 18 to 38, offering flexibility for various system sizes. In addition to the PTS valves, the portfolio includes ETS expansion valves, controllers, oil-free ball valves (OFC and OFB), and other components designed for liquid, suction, and discharge lines, providing OEMs with a comprehensive set of solutions for reliable system integration.
These valves offer easy integration with our chillers and heat pumps product portfolio, ensuring flexibility and reliability for HVAC&R professionals.
PTS stepper motor staging valves for fast, reliable surge prevention in oil-free centrifugal chillers and heat pumps. The valves open quickly at startup and release pressure at shutdown, enabling stable operation, optimal compressor pressure ratios, high flow capacity and long-term efficiency in demanding applications.