Solenoid Valve Selection Guide: What to Consider Before Choosing the Right Valve

Choosing the wrong solenoid valve doesn't just waste money; it causes leaks, pressure drop, and coil failures that show up weeks later as downtime. By then, the system is already down, and tracing the root cause back to a spec mismatch takes time most operations cannot afford.

The challenge is that solenoid valves look interchangeable on the surface. But two valves can share the same pipe size and pressure rating, yet behave differently depending on what flows through them or how the system is controlled.

This solenoid valve selection guide covers every factor that affects how to choose a solenoid valve, from actuation type and seal material to voltage and enclosure ratings. Valves used in industrial piping systems should also meet applicable ANSI (American National Standards Institute) requirements, which establish dimensional, performance, and safety standards widely recognized across North American industries.

Control Specialties stocks a broad range of options from ASCO valves, Burkert, Granzow, Magnatrol, and JD Gould, so the right product is almost always available once you know what you need.

Quick Solenoid Valve Selection Checklist:

This checklist is meant to give you a fast starting point before diving into detailed specifications. Each line reflects a common decision engineers make during valve selection.

Your Requirement	Preferred Solenoid Valve
Simple ON/OFF flow control	2-way solenoid valve
The system may reach zero pressure	Direct-acting valve
Safety-critical shutoff	Normally closed (NC) valve
Water or steam media	EPDM seal
Oil, fuel, or diesel media	FKM (Viton) seal
PLC-controlled system	24VDC coil
Food or pharmaceutical process	Stainless steel body & PTFE seal
Outdoor or washdown environment	IP65/IP67 or NEMA 4X rated valve

What is a Solenoid Valve? - A Quick Overview

A solenoid valve is an electromechanically operated device that opens or closes a fluid or gas line in response to an electrical signal. When current flows through the coil, it generates a magnetic field that moves a plunger, either opening or closing the flow path.

Remove the current, and a spring returns the valve to its default position. They’re the standard choice for automated on/off flow control in water treatment, HVAC, pneumatics, food processing, chemical handling, and dozens of other industries.

8 Factors to Consider When Selecting a Solenoid Valve

1. Valve Type: 2-Way, 3-Way, or 4-Way

Start here. The valve type tells you how many flow paths the valve manages, and choosing the wrong type means the system simply will not function as designed.

Valve Type	How It Works	Common Applications
2-Way	One inlet, one outlet. Opens or closes the flow.	Simple on/off for water lines & compressed air.
3-Way	One inlet, two outlets. Directs flow or exhausts.	Actuator control, diverting, & mixing.
4-Way	Two inlets and two outlets. Controls bi-directional actuators.	Double-acting cylinders & pneumatic actuators.

For example,

A cooling tower fill line uses a 2-way normally closed valve to stop the flow when the tank is full. A pneumatic gripper on a packaging line almost always requires a 4-way valve to open and close independently.

Selection Tip:

If your application requires basic on/off flow control, a 2-way valve covers it. If you are controlling an actuator or need to switch between two flow paths, move to a 3-way or a 4-way.

2. Direct-Acting vs. Pilot-Operated Solenoid Valves

Understanding the difference between direct-acting and pilot-operated solenoid valves is essential for proper selection.

While both designs may look similar externally, they operate very differently under real system conditions. The key distinction lies in how each valve uses system pressure, which directly affects performance, reliability, and flow capacity.

Choosing the right type ensures consistent operation and helps avoid performance issues in practical applications.

Direct-Acting Valves

Direct-acting valves move the plunger by using electromagnetic force alone. It works at any system pressure, including zero, which makes it the safe default for systems where pressure can fluctuate or drop entirely.

Pilot-Operated Valves

Pilot-operated valves use system pressure to assist in the opening and closing of valves. This means it can handle much larger orifice sizes with a smaller, more efficient coil. The tradeoff is that it requires a minimum pressure difference across the valve, typically 5 PSI or more, to function correctly. If the system pressure drops below that threshold, the valve may stick open or fail to close.

Direct-Acting Valve vs. Pilot-Operated Solenoid Valves: A Tabular Comparison

Factor	Direct Acting	Pilot Operated
Minimum Pressure	0 PSI (zero OK)	Typically 5+ PSI
Flow Rate	Low to moderate	High flow
Power Draw	Higher	Lower
Cost	Lower	Higher for large sizes
Response Time	Fast	Slightly slower

For large-bore or high-flow applications where pilot-operated valves are preferred, Magnatrol offers heavy-duty options in pipe sizes from 3/4" to 4" that handle demanding flow rates reliably.

Selection Tip:

If your system pressure can drop to zero at any point, even briefly, choose a direct-acting valve. Pilot-operated valves are ideal for high-flow applications where the pressure differences stay consistent.

3. Normally Open vs. Normally Closed Solenoid Valves

The default valve position, what happens when power is cut, is a safety decision, not just a wiring preference. Get this wrong and a power interruption can cause a hazardous condition rather than a safe one.

Normally Open (NO) Valves

Normally Open (NO) Valves stay open with no power applied. Flow continues until the coil is energized to close it. This configuration makes sense when a power failure must not interrupt the flow. For example, cooling water to a motor or heating fluid in a process that cannot run dry.

Normally Closed (NC) Valves

Normally Closed (NC) valves stay shut with no power applied. To allow flow, the coil must be energized. This means a power failure automatically stops the flow, which ensures a safe outcome in most industrial applications.

In most industrial systems, normally closed is the standard starting point. Fuel lines, chemical injection, and any application where uncontrolled flow creates a hazard should always default to Normally Closed unless there is a specific reason to do otherwise.

Selection Tip:

If a power failure should stop the flow, choose normally closed. If uninterrupted flow is required during a power loss, such as emergency cooling, choose normally open.

4. Media Compatibility

No other factor causes more premature valve failures than choosing a valve that is incompatible with the fluid or gas flowing through it. The media determines both the seal material and the body material.

Media	Recommended Seal	Avoid	Recommended Brand
Water/Steam	EPDM	FKM & Nitrile	ASCO & Burkert
Oil/Fuel/Diesel	FKM (Viton)	EPDM	ASCO & Granzow
Air/Inert Gas	Nitrile (NBR)	EPDM (steam apps)	ASCO & Granzow
Chemicals/Solvents	PTFE/FFKM	Standard rubber	Burkert
Food/Pharma Fluids	EPDM/PTFE	Nitrile	Burkert
Hydraulic Oil	FKM/Nitrile	EPDM	ASCO

For general industrial use, ASCO solenoid valves and Granzow both cover the most common media types. For food-grade or pharmaceutical applications, Burkert valves are specifically designed for clean processes and meet the hygiene standards required in those environments.

Selection Tip:

Start with the media. Identify exactly what is flowing through the valve, including temperature, concentration, and any additives, before selecting any other component.

5. Body Material: Brass vs. Stainless Steel Solenoid Valve

The body material determines how the valve holds up against the media it contacts, the operating environment, and pressure over time. The brass vs. stainless steel solenoid valve decision comes down to three things:

• Media Corrosiveness
• Temperature
• Whether Hygiene Requirements Apply

Brass Material-Based Valve

• Ideal for water, air, natural gas, & non-corrosive fluids
• Handles pressures up to ~300 PSI
• Operates reliably up to ~180°F
• Cost-effective for general-purpose applications
• Commonly used in ASCO & Granzow standard valves

Stainless Steel Material-Based Valve

• Suitable for corrosive or chemical media
• Performs well above 180°F & under higher pressure
• Preferred for marine, outdoor, & harsh environments
• Meets hygienic standards (food & pharma applications)
• Prevents contamination in sensitive systems

When specifying body materials for pressurized service, engineers should reference ASME (American Society of Mechanical Engineers) standards, which govern pressure ratings and materials for valves and piping components.

ASME guidelines help ensure the selected body material can safely handle the system's operating pressure and temperature over the long-term, a step that is especially important in steam, high-pressure hydraulic, and process chemical systems.

Selection Tip:

Use brass for standard water, air, and gas service. If your media is corrosive, your environment is harsh, or your process requires hygienic-grade materials, choose stainless steel; the cost difference is small compared to a premature replacement.

6. Seal Material

The seal is the first component to wear out in a solenoid valve. It contacts the media directly, flexes every cycle, and has to withstand both the fluid and operating temperature.

Choosing the wrong solenoid valve seal material shortens valve life, sometimes from years to weeks.

Here’s a straightforward breakdown of the most common seal materials and where they work:

• EPDM: Best for water, steam, & hot fluids up to 300°F. Not compatible with oils or hydrocarbons. The standard seal for steam service.
• FKM (Viton): Best for oils, fuels, diesel, & most hydrocarbons. Handles temperatures up to 400°F. Avoid using steam or ketones.
• Nitrile (NBR): Reliable for air, water, & hydraulic oil at moderate temperatures. Not suitable for ozone-rich environments or aggressive solvents.
• PTFE: Handles aggressive chemicals, acids, & pharmaceutical fluids. Temperature-resistant up to 450°F. The go-to for demanding chemical service.
• FFKM (Kalrez): Highest chemical and temperature resistance available. Used in pharmaceutical, semiconductor, & highly corrosive environments where cost is secondary to performance.

Both ASCO valves and Burkert offer multiple seal options across their product lines. Always verify the seal material is explicitly stated in the part number or datasheet; never assume the default seal is compatible with your media.

Selection Tip:

Match the seal to both the media and the temperature range, not just one. A chemically compatible seal used outside its temperature rating will fail just as quickly as an incompatible seal.

7. Pressure and Flow Requirements

Two parameters define valve performance in real systems: pressure rating and flow coefficient (Cv/Kv). Both must align with actual operating conditions.

Pressure Rating

The pressure rating defines the maximum pressure the valve body and seals can safely handle.

• Always select a valve rated above your system’s maximum pressure, not just average operating pressure.
• Exceeding limits can lead to seal deformation, leakage, or body damage.
• Consider pressure spikes, not just steady-state values.

Flow Coefficient (Cv/Kv)

• Cv (Coefficient of Flow): Used in US systems, represents flow (GPM) at 1 PSI pressure drop
• Kv (Metric equivalent): Represents flow (m³/h) at 1 bar pressure drop
• Conversion: Kv ≈ Cv × 0.86

Cv/Kv Sizing Impact

• Undersized Cv/Kv: Causes flow restriction & backpressure
• Oversized Cv/Kv: Increases cost & may create instability or water hammer
• Correct sizing ensures efficient & stable flow performance

Water Hammer (Often Overlooked)

Water hammer occurs when flow stops suddenly, creating a pressure surge.

• Common in high-flow or long pipeline systems
• Oversized valves, with fast closing times, increase risk
• Can damage downstream fittings & piping

How to Manage It:

• Use slow-closing valves
• Install surge arrestors
• Size Cv/Kv appropriately from the start

For example,

For large pipe sizes (typically 2” and above) or high-volume flow systems, engineers often evaluate solutions like Magnatrol valves, which are designed for higher Cv/Kv capacities than standard catalog options.

Selection Tip:

Calculate the required Cv for your flow rate and pressure drop before selecting a valve. For large pipe sizes or high-volume flow, 2" bore and above Magnatrol valves are built for exactly that service and carry Cv ratings that standard catalog valves cannot match.

8. Solenoid Valve Voltage: AC vs. DC

Coil voltage is a fixed specification; a 24VDC coil wired to a 120VAC supply will burn out immediately. Confirming the control voltage before ordering is a five-second check that prevents an expensive mistake.

In modern systems, 24VDC is the most common choice for PLC control, while AC coils are still common in legacy or standalone installations.

Alternating Current (AC)

AC-powered coils, such as 120VAC or 240VAC, are still widely used in traditional and heavy industrial setups. They are often selected where direct AC power is available, and no control system is involved.

Key Points:

• Common in legacy systems & standalone applications.
• Simpler wiring without the need for DC conversion.
• More tolerant to voltage fluctuations.
• Does not require a separate DC power supply.
• 240VAC is used in heavy industrial or international installations.

Where It Fits Best:

AC coils are typically used in older systems or where valves are directly connected to an AC power source without PLC control.

Direct Current (DC)

DC-powered coils, typically 24VDC, are the standard in modern automated systems. They’re widely used in PLC-controlled environments due to their safety, efficiency, and compatibility with control hardware.

Key Points:

• Common in PLCs & automation panels.
• Safer for low-voltage control circuits.
• Faster response time & consistent operation.
• Easily integrates with digital output modules.
• Requires a regulated DC power supply.

Where It Fits Best:

Engineers typically choose DC coils in new industrial builds where automation and precise control are required.

Selection Tip:

Check the output voltage of your PLC or control relay before ordering. In a new automated system, 24VDC is almost always the right call. In an older system, match whatever voltage is already present rather than introducing a second supply rail.

Environmental and Enclosure Ratings

Where the valve is installed affects how long it lasts, sometimes more than the internal specifications. A solenoid valve rated for dry indoor use will degrade quickly in a washdown zone, and one rated for general industrial use is not safe in a classified hazardous area.

IP65 Rating

Fully dust-tight and protected against water jets from any direction. Suitable for outdoor installations, washdown areas, and environments with regular exposure to moisture or spray.

IP67 Rating

Includes all IP65 protection plus resistance to temporary submersion (up to 1 meter). Commonly used in flood-prone areas or facilities with high-pressure cleaning, such as food processing.

NEMA 4X

North American standard for corrosion-resistant and washdown-rated enclosures. Protects against rain, splashing, hosedown, and harsh chemical environments. Preferred where NEMA compliance is required.

Explosion-Proof Ratings

Required for hazardous locations (e.g., refineries, grain handling, oil & gas). Designed to contain internal ignition and prevent external hazards. ASCO solenoid valves offer certified options for Class 1 Division 1 and Division 2 environments.

For hazardous area applications, classified as Class 1, Division 1 or Division 2 under NEC standards, the solenoid valve coil must carry an explosion-proof certification. ASCO valves offer a broad range of explosion-proof coil options that meet these requirements, which is one reason they are widely specified in petrochemical, oil, and gas facilities.

Selection Tip:

If your installation site involves chemicals, flammable gases, fine dust, or high-pressure washdown, check the IP or NEMA rating before ordering. A standard valve will fail quickly in those conditions.

3 Common Solenoid Valve Selection Mistakes

These errors come up repeatedly in the field. Each one is easy to avoid once you know what to look for.

Brand Selection Guide

Each brand in Control Specialties' product line has a defined strength. Matching the brand to the application, rather than defaulting to one name for everything, produces better results and cleaner specifications.

ASCO Valves

ASCO solenoid valves are typically the default starting point for most industrial applications. They cover the widest range of media, pipe sizes, configurations, and coil voltages, and their replacement parts are easy to source.

While ASCO offers a broad range of valve configurations, two of the most commonly used options are the ASCO 8551 direct-mount solenoid valve and the ASCO 8327 3-way solenoid valve. The 8551 is widely selected for manifold and direct-mount installations, while the 8327 is preferred for pilot and actuator control, making both reliable choices across a wide range of industrial applications.

For water, air, gas, oil, and steam standard brass or stainless steel bodies, ASCO covers most requirements out of the box. To select the right valve, explore the ASCO catalog, a solenoid valve selection guide, to order the right valve to meet your specific requirements.

Burkert

The right choice when precision matters or when the application involves clean media, food processing, pharmaceutical production, biotech, and laboratory systems. Burkert solenoid valves meet hygiene certifications that general-purpose lines do not carry.

Granzow

A practical and cost-effective option for general industrial applications. Granzow covers common media types, water, air, and mild chemicals, with a straightforward product line that works well for facilities that need reliable performance without specialty requirements.

Magnatrol

Purpose-built for large-bore applications. If the pipe is 1.5" or larger and the flow volume is high, Magnatrol solenoid valves should be evaluated. Standard catalog valves often cannot reach the Cv ratings that these applications demand.

JD Gould

The right call for specialty and edge-case applications, cryogenic service, unusual media, and custom configurations. If no standard valve fits the requirement, JD Gould typically has something that does.

Brand	Strengths	Typical Application
ASCO	Widest range & proven reliability.	Water, air, gas, & oil.
Burkert	Precision & clean media.	Food, pharma, & biotech.
Granzow	Value & broad compatibility.	General industrial.
Magnatrol	Large pipe sizes & high flow.	2"–4" pipe for heavy flow.
JD Gould	Specialty & unusual configurations.	Cryogenic & custom media.

When to Consult an Expert

Most solenoid valve selections follow a clear path once pressure, media, and control requirements are defined. However, some applications go beyond standard catalog specifications. In these cases, selecting a valve without proper validation often leads to performance issues, rework, or costly downtime later.

Consider consulting a specialist if your application involves:

• Unusual media such as aggressive chemicals, high-viscosity fluids, slurries, or cryogenic gases.
• Highly variable system pressure or conditions where pressure may drop to zero unpredictably.
• Hazardous locations requiring NEC or ATEX certification validation.
• Food-grade, pharmaceutical, or medical compliance requirements.
• Large pipe sizes or flow demands beyond standard catalog ranges.

A short discussion upfront can prevent extended troubleshooting after installation. If your system includes any of the above conditions, connect with our experts to confirm the right valve selection before placing an order.

Ready to Select Your Valve?

Valve failures are rarely random. They trace back to a material mismatch, a wrong configuration, or a spec that was never checked. The factors covered in this solenoid valve selection guide help you make decisions by identifying a valve that runs for years from one that fails in months.

Control Specialties stocks solenoid valves from ASCO, Burkert, Granzow, Magnatrol, and JD Gould for standard and specialty applications. Most orders ship quickly, and the team can assist with application-specific questions when the selection is not straightforward.

Use this guide as your checklist, confirm the specifications before you order, and the right valve will be in place the first time.