Control Valves for Data Center Liquid Cooling Systems
Control valves regulate coolant flow in data center liquid cooling loops. They are used for bypass control in CDU temperature regulation, flow balancing across multiple cooling circuits, isolation for maintenance, and emergency shutoff. Motorized valves enable automated control from BMS or CDU controllers.
How It Works
A control valve modulates the flow of coolant through a loop by varying the opening of the valve body. In a CDU bypass circuit, a 3-way motorized valve diverts coolant between the heat exchanger and the bypass line to maintain the target supply temperature. In a rack manifold, adjustable needle valves balance flow across multiple server connections. Motorized actuators receive control signals (0–10V, 4–20mA, or digital) from the CDU controller or BMS and position the valve accordingly.
Applications
- CDU bypass temperature control (3-way mixing valve)
- Flow balancing across rack cooling circuits
- Isolation valves for maintenance and service
- Emergency shutoff in leak detection response
- Pressure regulation in cooling loops
- OEM CDU and cooling system assemblies
- BMS-integrated cooling control systems
- Variable flow cooling infrastructure
Key Technical Specifications
| Valve Types | Ball, butterfly, globe, needle, 3-way mixing/diverting |
| Actuation | Motorized electric, pneumatic, manual handwheel |
| Control Signal | 0–10V, 4–20mA, on/off, Modbus RTU/TCP |
| Sizes | DN10 to DN100; custom sizes available |
| Working Pressure | Up to 16 bar — confirm by valve type |
| Temperature Range | -20°C to +150°C — material dependent |
| Body Materials | Stainless steel 316L, brass, PVDF, cast iron |
| Leakage Class | ANSI/FCI 70-2 Class IV/V options |
| Fail Position | Fail-open, fail-closed, fail-last (spring return or hold) |
| Certifications | Options available depending on configuration and manufacturing partner. Please specify project requirements. |
Specifications are indicative. Final parameters depend on manufacturing partner and project configuration. Contact us with your specific requirements.
Available Configurations
- 2-way motorized ball valve — on/off or modulating flow control
- 3-way motorized mixing valve — CDU bypass temperature control
- 3-way motorized diverting valve — flow distribution control
- Manual ball valve — isolation and maintenance shutoff
- Adjustable needle valve — manual flow balancing
- Butterfly valve — large diameter, low pressure drop
- Globe valve — precise modulating control
- Spring-return actuator — fail-safe position on power loss
Materials
Operating Conditions
- Working pressure: up to 16 bar — confirm by valve type and size
- Temperature: -20°C to +150°C — dependent on body and seal materials
- Fluid compatibility: confirm glycol concentration and inhibitor chemistry
- Control signal: specify 0–10V, 4–20mA, on/off, or digital protocol
- Fail position: specify fail-open, fail-closed, or fail-last for safety
- Actuator power: specify available voltage (24VAC, 24VDC, 230VAC)
- Environment: specify IP rating requirement for actuator enclosure
Selection Guide
Control valve selection requires: (1) Function — 2-way for on/off or modulating control; 3-way for mixing or diverting (CDU bypass); (2) Size — determined by required flow rate and allowable pressure drop (Cv/Kv calculation); (3) Actuation — motorized for automated control; manual for maintenance isolation; (4) Control signal — match to CDU controller or BMS output; (5) Fail position — specify the safe position on power loss (fail-open for cooling continuity; fail-closed for leak isolation); (6) Body material — stainless steel for corrosion resistance; brass for lower cost in compatible applications.
OEM & Custom Manufacturing
Custom valve configurations are available for OEM CDU and cooling system manufacturers. Custom options include non-standard sizes, proprietary actuator interfaces, specific material combinations, integrated position feedback, and private label manufacturing. Provide your flow requirements, control interface specification, and installation drawing for a valve selection review.
Submit Custom RequirementQuality & Testing
Control valves for data center liquid cooling require seat leakage testing, actuator function testing, and control signal calibration. Fail-safe position should be verified by simulating power loss. Motorized valve actuators should be tested for full stroke operation and position feedback accuracy.
Frequently Asked Questions
What type of valve is used for CDU bypass temperature control?
A 3-way motorized mixing or diverting valve is used for CDU bypass temperature control. The valve mixes hot return coolant with cooled supply coolant (mixing configuration) or diverts supply coolant between the heat exchanger and bypass line (diverting configuration) to maintain the target supply temperature.
What does fail-open vs. fail-closed mean for a cooling valve?
Fail position describes where the valve moves on power loss. Fail-open maintains coolant flow for cooling continuity — appropriate for valves in the main cooling circuit. Fail-closed stops flow — appropriate for isolation valves in leak detection response systems. Specify the required fail position based on the safety requirements of the application.
What control signal is used for motorized valves in data center cooling?
Common control signals include 0–10V analog (most common for simple modulating control), 4–20mA (for longer cable runs with noise immunity), on/off (for simple open/close applications), and Modbus RTU or TCP (for digital integration with BMS or DCIM platforms). Specify the output type of the CDU controller or BMS when selecting a valve actuator.
How is flow balancing achieved across multiple rack cooling circuits?
Flow balancing can be achieved with fixed orifices (passive, set at commissioning), adjustable needle valves (manual adjustment), or motorized control valves with flow measurement (active, automated). Fixed orifices are the simplest and lowest cost; motorized valves with flow feedback provide the most precise and adaptive balancing.
Need Control Valves for Your Project?
Send your connection size, coolant type, flow requirements and estimated quantity. Our team will review the application and identify suitable manufacturing options.