Pilot Operated Normally Closed High Temperature Solenoid Valve — SS304, Viton, Steam up to 180 °C

Cematic's pilot operated normally closed high temperature solenoid valve in stainless steel is the solenoid valve that combines the four most demanding requirements of industrial fluid control in a single component: pilot operated principle for high flow with low power consumption, SS304 body for corrosion resistance, Viton seal for temperatures up to 180 °C, and NC configuration for automatic safety shut-off in case of power failure. Therefore, it is the correct option for high-temperature processes — steam, hot water, thermal oils — where no other pilot operated valve in Cematic's catalog reaches the required thermal range.

Unlike the NC SS304 pilot operated valve with NBR seal (limited to 80 °C), this version with Viton (FKM) seal operates with hot water up to 150 °C, process oils up to 150 °C, and steam up to 180 °C — conditions that would degrade NBR in weeks and make any solenoid with a standard seal unfeasible.

Operating principle — Pilot Operated Normally Closed (NC)

In the de-energized state (coil de-energized): the pilot is closed, and the spring keeps the main plunger in the closed position — the fluid does not flow. When the coil is energized, the pilot opens, the pressure in the upper chamber of the plunger drops, and the pressure difference between inlet and outlet displaces it, opening the fluid path. When de-energized, the pilot closes, and the spring automatically returns the plunger to the closed position.

Critical operating condition: A minimum differential pressure of 0.05 MPa (0.5 bar / 10 psi) between inlet and outlet is required for the pilot operated mechanism to open. If the system can start or operate with zero differential pressure, the correct option is the direct acting NC solenoid in SS304 with Viton →

Temperature ranges by fluid — the key data for this product

Unlike other solenoids that specify a single maximum temperature, this valve has differentiated ranges depending on the controlled fluid — critical information for correct specification:

The Viton seal is the only elastomer that allows these ranges in continuous operation. Consequently, this valve is the correct choice for any process where the fluid temperature exceeds 80 °C — the limit of the standard NBR seal.

Construction materials

• Body: Stainless steel 304 (SS304) — corrosion resistance for process water, steam, aqueous solutions, and industrial fluids at elevated temperatures. No metallic ion contribution to the fluid.
• Plunger and pilot: Stainless steel — resistant to corrosion and process thermal conditions.
• Seat seal: Viton (FKM) — compatible with temperatures up to 180 °C in steam, 150 °C in hot water and oils, and resistant to synthetic oils, fuels, and aggressive process fluids. Key differentiator compared to all pilot operated valves with NBR seals in the catalog.
• Coil: Resin encapsulated, IP65 protection — suitable for humid environments, with condensation and industrial dust. Low power consumption thanks to the pilot operated principle.
• Connection: NPT female thread — industrial standard in Mexico, compatible with stainless steel and carbon steel piping.

Technical specifications

Voltage selection

• 24 VDC: Standard in industrial control cabinets with PLC and DC power supply. The most common option in new installations and modern automated systems.
• 110 VAC: For 110 V single-phase circuits available in the field — the most widespread voltage in industry in Mexico and the United States.
• 220 VAC: For power panels with bipolar distribution or European voltage standard.

Fluid compatibility

• ✅ Steam up to 180 °C — the differentiating application of this product; no other Cematic NC pilot operated valve reaches this temperature
• ✅ Hot water up to 150 °C — heating systems, heat exchangers, and industrial thermal processes
• ✅ Mineral and synthetic oils up to 150 °C — lubrication circuits and heat transfer with oil
• ✅ Process water and purified water — no metallic ion contribution from SS304
• ✅ Compressed air up to 1.0 MPa — industrial pneumatic service
• ⚠️ Differential pressure less than 0.05 MPa: the pilot operated valve cannot open — use a direct acting NC solenoid in SS304 with Viton
• ⚠️ Fluids with suspended solids: install an upstream in-line filter — the pilot orifice is sensitive to particles, especially with high-temperature fluids
• ❌ Concentrated acids, halogenated solvents, fluids with high chlorides at temperature: SS304 may be insufficient — consult Cematic's technical team for SS316 requirements

When to choose this valve vs. other Cematic NC pilot operated valves

• Pilot operated NC Brass + NBR (up to 80 °C): For water, air, and oils at ambient temperature. The lowest cost option with pilot operated principle and NC closure. See pilot operated NC brass solenoid →
• Pilot operated NC SS304 + NBR (up to 80 °C): For fluids requiring SS304 but at standard temperature — purified water, moderate aqueous solutions, diameters up to 2". See pilot operated NC SS304 NBR solenoid →
• Pilot operated NC SS304 + Viton High Temperature (this product): For steam up to 180 °C, hot water up to 150 °C, and oils at elevated temperatures, with automatic safety shut-off and SS304 body. The highest thermal specification option in Cematic's NC pilot operated family.

Main industrial applications

Industrial steam control with safety shut-off
This is the exclusive application of this product in Cematic's entire pilot operated family. The pilot operated normally closed high temperature solenoid valve in SS304 with Viton controls the flow of steam up to 180 °C with automatic shut-off in case of power failure. Therefore, it is the standard component in plant steam distribution systems where NC safety shut-off, low pilot coil consumption, and SS304 + Viton thermal resistance are simultaneously required.

Industrial heating systems with high-temperature hot water
In hot water circuits at temperatures above 80 °C — which rule out any NBR seal — this NC pilot operated valve with Viton controls the flow by zones or circuits with automatic shut-off in case of power failure. Additionally, the low consumption of the pilot coil is relevant in installations with multiple heating zones active simultaneously, where the accumulated consumption of high-power direct-acting coils impacts the electrical sizing of the control system.

Control of thermal and process oils at elevated temperatures
In centralized lubrication systems with hot oil and heat transfer circuits with synthetic or mineral oils up to 150 °C, the Viton seal resists thermal and chemical conditions that would degrade NBR in a few weeks. Likewise, the SS304 body ensures compatibility with industrial process oils and no contribution of metallic contaminants to the lubricating fluid.

CIP and SIP processes with high-temperature hot water
In clean-in-place (CIP) and sterilize-in-place (SIP) systems with hot water at temperatures above 80 °C, this NC pilot operated solenoid valve combines the three process requirements: automatic shut-off at the end of the cycle (NC), thermal resistance of the Viton seal, and purity of the SS304 body without metallic ion contribution to the cleaning water. Consequently, it is the correct component for high-temperature cleaning and sterilization processes in food and pharmaceutical plants.

For the complete range of solenoid valves, see solenoid valve collection →

Technical Data Sheet