12V DC vs 24V DC Solenoid Valves: Which Is the Right Fit for Your Project?

In modern fluid control and automation systems, even small design choices can affect safety, reliability, and lifecycle cost. One of the most common questions our engineering team hears is:

👉 Should I use a 12V DC solenoid valve or a 24V DC solenoid valve?

Both 12V and 24V DC solenoid valves operate at safe low voltages, are widely available, and serve similar functions in various applications. However, the choice between 12V and 24V significantly influences heat generation, duty cycle, wiring layout, and compatibility with the existing power system.

At Rotex Automation, we’ve supplied millions of solenoid valves across industries like automotive, power, water treatment, oil & gas, pharma, and food processing. We know from decades of experience that choosing the right voltage isn’t just about availability—it’s about performance, safety, and lifecycle costs.

This detailed guide breaks down everything you need to know to make an informed choice.

How DC Solenoid Valves Work?

Before diving into voltage options, let’s revisit the basics.

A DC solenoid valve is an electromechanical device that controls the flow of a fluid or gas. It combines:

● A solenoid coil that generates a magnetic field when energized

● A plunger or armature that moves in response to the magnetic field and allows the fluid or gas to flow or stop

● A valve body with flow control ports (Inlet, Outlet, exhaust ports, depending on the valve design). The fluid/gas flows through the ports.

When the solenoid is energized, electrical power is supplied to the coil, generating a magnetic field. This magnetic force acts on the plunger (or armature), causing it to shift position. Depending on the design, this movement either opens the flow path or closes it, thereby controlling the fluid flow.

Why Choose Low DC Voltage (12V or 24V)?

● Operator Safety: Both operate at safer low-voltage levels, significantly reducing the risk of electrical shock during installation and maintenance.

● Compatibility: Many systems are already designed around 12V DC (such as automotive and solar-powered setups) or 24V DC (common in industrial control panels and automation systems).

● Energy Efficiency: DC solenoid coils operate without the magnetic vibration associated with AC types, making them quieter and often cooler in operation, especially under steady or continuous duty conditions.

12V Solenoid Valve: Features and Uses

Key Advantages

● Runs directly from 12V battery systems (cars, trucks, tractors, solar panels).

● Lower voltage makes it inherently safer to handle in mobile applications.

● Easy to integrate into portable or remote systems.

Typical Applications

● Automotive: fuel shut-off, emission control, coolant circuits.

● Agriculture: irrigation valves in battery-powered field systems.

● Portable Equipment: compressors, cleaning machines, vending systems.

● Solar-powered sites: remote water pumps or fluid dosing units.

Considerations

● Higher current draw: For the same power rating, 12V coils draw roughly double the current of 24V coils.

● Heat buildup: May generate more heat under continuous duty due to high operating current

● Cable length limits: Recommended for shorter cable runs due to voltage drop sensitivity.

24V Solenoid Valve: Features and Uses

A 24V solenoid valve is widely used in industrial automation because it aligns with standard PLC and control system power supply voltages.

Key Advantages

● Lower current draw for the same wattage → less heat, longer coil & insulation life.

● Handles longer wiring distances with minimal voltage drop.

● Compatible with PLC panels, SCADA systems, and industrial control networks

● 24V DC is widely adopted in industrial control cabinets, HVAC systems, and water treatment applications, making integration straightforward and consistent with typical control voltages.

● Often runs quieter and cooler under continuous duty.

Typical Applications

● Factory automation: conveyor systems, packaging, robotics.

● HVAC Systems: heating/cooling system controls, Chiller, and AHU control

● Water treatment plants: dosing, distribution, and filtration control.

● Process industries: oil & gas skids, chemical batching, power plants.

Considerations

● Slightly less portable than 12V (requires 24V supply).

● A DC-DC converter may be needed if only 12V batteries are available.

Best for stationary or industrial applications with long cable runs or continuous duty cycles

12V vs 24V Solenoid Valve Difference (Comparison Table)

Here’s a side-by-side look at the practical differences:

Parameter	12V Solenoid Valve 12V	24V Solenoid Valve 24V
Power Source	Cars, trucks, solar, batteries	PLCs, control panels, industrial power
Current Draw	Higher (warmer coils)	Lower (cooler operation)
Voltage Drop Sensitivity	High – short cable runs preferred	Low – handles longer runs
Duty Cycle	OK for intermittent use	Better for continuous duty
Safety	Extra-low, very safe	Low-voltage safe
Common Industries	Automotive, agriculture, portable OEM	Factory automation, HVAC, water plants

Key Performance Factors Engineers Should Consider

When choosing between 12V and 24V solenoid valves, think beyond voltage labels. The following factors often determine success or failure in real-world use:

1. Duty Cycle

● Intermittent use (on/off occasionally): 12V or 24V both work.

● Continuous Energization: 24V performs better due to cooler coils.

2. Heat Buildup

● Higher current at 12V increases coil temperature over time

● For long service life, 24V provides thermal advantage

3. Cable Distance

● Voltage drop is a bigger issue at 12V.

● 24V accommodates distributed plant layouts..

4. Power Supply Stability

● Vehicle batteries fluctuate (10–14V) → valves must tolerate this.

● Industrial 24V supplies are generally more stable and regulated.

5. Availability of Spare Parts

● 12V parts dominate the automotive market.

● 24V spares are standard in industrial supply chains.

Application-Specific Guidance

Automotive & Mobile Equipment → 12V Solenoid Valve

Nearly every car, truck, or piece of construction equipment uses a 12v electric solenoid valve for fuel shut-off, EGR, or transmission control. Why? Because vehicles already run on 12V DC batteries.

Industrial Automation & Manufacturing → 24V Solenoid Valve

Most industrial solenoid valves use 24V because PLCs, relays, and sensors all share the same voltage. It simplifies wiring and improves reliability over long distances.

Agriculture & Irrigation → Both Options

● Portable, solar, or battery-driven systems → 12V

● Stationary pumps or centralized controllers → 24V

Water Treatment & Utilities → 24V Solenoid Valve

For water dosing, filtration, or municipal distribution, 24V is standard for control panels and SCADA systems.

Rotex Expertise in Low Voltage Solenoid Valves

Tip 1: Match coil voltage to your existing power supply—don’t design unnecessary conversions.

Tip 2: For long cables or continuous operation, go 24V.

Tip 3: For battery-powered mobile use, stick with 12V.

Tip 4: Always check media pressure, flow (Cv), and temperature before finalizing.

Tip 5: Ask for the right IP rating (IP67/IP68) if the valve will face dust, water, or outdoor use.

Practical Tips Before You Order

At Rotex, we understand that selecting the right solenoid valve is about more than just ports and coils—it’s about solving real-world problems.
Custom-built 12V & 24V solenoid valves for air, water, gas, oil, and steam.

● Designs tested for 20+ million cycles and harsh conditions.

● Rugged enclosures: Flameproof, weatherproof, Intrinsically Safe, latch and IP-rated options.

● Global certifications: ATEX, CE, UL, INMETRO, PESO, SIL2/3.

● Support for industries from automotive to water treatment to oil & gas.

Whether you need the best solenoid valve for automotive or a reliable 24V solution for process automation, our engineers will guide you.

Conclusion

Choosing between a 12V solenoid valve and a 24V solenoid valve isn’t just a technical detail—it directly impacts reliability, safety, and cost.

● Select 12V for mobile, battery-powered, and remote systems.

● Select 24V for industrial, continuous duty, and long-distance control environments.

At Rotex Automation, we’ve been helping industries worldwide make these choices for decades. With proven designs, custom engineering, and global support, we’re here to ensure your project runs smoothly.

Still unsure which low-voltage solenoid valve is right for you?

Our engineering team can analyze:

● Power system type

● Duty cycle

● Media characteristics

● Ambient environment

● Compliance requirements