NAMUR Valves - High Temperature Applications 0 to 180 F (-18 to 82 C)

Product Overview

The Automatic Valve D20 Series NAMUR Valves for High Temperature Applications are solenoid pilot directional control valves engineered for direct mounting to pneumatic valve actuators in process environments where ambient temperatures reach 0 to 180 F (-18 to 82 C). These valves serve as pilot controls that direct the actuator in flow process applications, replacing separate tubing runs with a compact, standardized NAMUR interface connection defined by VDI/VDE 3845.

The D20 Series is available in two body height variants: the D2003 (1-1/4" body height) and the D2013 (1" body height), both with 1/4" port size and NPT port threads. Valve functions include 3/2 normally closed, 5/2 single or double solenoid, and 5/3 closed center, open center, or power center configurations. Maximum flow capacity is 1.8 Cv (1800 Nl/min) for 3/2 and 5/2 functions, and 1.4 Cv (1400 Nl/min) for 5/3 functions.

The high temperature configuration is identified by the high-temp conduit coil option (coil code CT), which uses a 1/2" conduit with 30" leads rated for ambient temperatures up to 180 F (82 C). The valve body uses aluminum bar stock construction with Buna-N seals and an aluminum spool. The solenoid pilot operates on full air line pressure, is guaranteed against burnout, and is hermetically sealed as a watertight molded unit.

For design engineers specifying pneumatic actuator controls on heat exchangers, steam isolation valves, high-temperature process lines, and industrial furnace controls, the D20 Series high-temperature NAMUR valve provides a direct-mount, standardized solution that eliminates external tubing, reduces leak paths, and simplifies system maintenance.

H2: Key Engineering Features

• High Temperature Conduit Coil (CT) - 1/2" conduit coil with 30" leads rated for ambient temperatures up to 180 F (82 C), providing reliable solenoid performance in sustained high-heat environments without burnout.
• Compact Balanced Spool Design - Balanced spool construction delivers compact size, low profile, and high performance, enabling direct mounting in tight actuator installations typical of process plant valve skids.
• Solenoid Pilot - Full Line Pressure Shifting - Three-way pilot uses full air line pressure (35-150 psig internal supply) to shift the valve, ensuring fast and complete spool actuation without intermediate pilot regulators.
• Tapered Tee-Seal - Self-Cleaning Design - Bidirectional tapered Tee-Seal flexes to clean the spool on every stroke, mechanically locked with no spiral twist or extrusion, wiping away air line sediment and preventing sticking problems even in contaminated process air environments.
• Weather-Proof Hermetically Sealed Coil - Solenoid coil is hermetically sealed as an integral watertight molded unit, providing robust protection against moisture, humidity, and outdoor environments at process plant installations.
• Push Non-Locking Manual Override - Standard push non-locking manual override allows the valve to be actuated manually during electrical failure or for quick cycle testing without requiring special tools, reducing commissioning and troubleshooting time.
• Field Convertible to External Pilot Supply - The pilot supply can be field converted from internal to external, accommodating applications where inlet pressure falls below the 35 psig minimum pilot requirement, or where independent pilot supply is required.
• NAMUR Interface per VDI/VDE 3845 - Standardized direct-mount interface per VDI/VDE 3845 eliminates external tubing and fittings between valve and actuator, reducing leak points, minimizing dead volume, and accelerating actuator response.
• SAE Tested - 20 Million Cycle Durability - Proven reliable per SAE specifications with rust and water injected every 864,000 cycles for 20 million total cycles, demonstrating suitability for continuous high-cycle process automation service.
• Convertible 3/2 and 5/2 Configurations - The balanced spool construction allows ports to be plugged for 2-way or 3-way function, or restricted for inexpensive cylinder exhaust speed control, providing configuration flexibility without replacing the valve body.

Technical Specifications

General Specifications

Temperature Ratings

The high temperature configuration uses the CT (High Temperature Conduit) coil option, rated for ambient temperatures up to 180 F (82 C). Standard weather-proof coils are limited to 123 F (50 C) ambient.

Important: For media temperatures below 40 F (4 C), compressed air must be free of water vapor to prevent ice formation inside the valve. When specifying for temperatures above 123 F (50 C), the high-temp conduit coil option (CT) must be selected.

Electrical Data (Solenoid Pilot Valves)

All solenoid coils are rated for continuous duty. The high-temp conduit coil (CT) uses 1/2" conduit with 30" leads. Standard DIN coils are rated for 123 F (50 C) maximum ambient.

Electrical Connection Options

Flow Performance Data

Flow performance data for D20 Series NAMUR valves. Values shown for D2003 (1-1/4" body) and D2013 (1" body) variants.

Certifications & Compliance

Typical Applications & Industries

Oil, Gas, and Petrochemical Processing

• Pilot valve control of automated ball valves, globe valves, and butterfly valves on high-temperature process headers, heat exchangers, and product transfer lines operating at sustained elevated temperatures.
• Steam distribution and condensate return system valve actuator control where ambient temperatures near the valve exceed standard coil ratings and the CT high-temp coil option is required.
• Flare stack knockout drum isolation and hot gas bypass valve control, where reliable pilot actuation must be maintained in high-heat radiant environments.
• Regenerative processes in refineries and chemical plants involving hot gas or vapor streams that require reliable pneumatic actuator control without valve sticking or seal degradation.

Power Generation and Utilities

• Boiler feed water, steam extraction, and turbine bypass valve actuator pilot control in power generation facilities where ambient temperatures near turbine halls and boiler rooms exceed 100 F.
• Heat recovery steam generator (HRSG) valve control and combined cycle plant auxiliary valve automation in high-ambient areas near hot gas ducts and steam pipework.
• District heating and industrial steam distribution system automated valve control requiring pilot valves rated for sustained elevated ambient operating conditions.

Food and Beverage Processing (High-Temperature CIP/SIP)

• Clean-in-place (CIP) and steam-in-place (SIP) circuit valve actuator control in food and beverage processing plants where hot water and steam cleaning cycles create elevated ambient temperatures around installed valve assemblies.
• Pasteurization line and retort vessel pressure control valve pilot automation in areas with consistent high-temperature ambient conditions near process equipment.
• Aseptic filling line valve control in environments with high radiant heat from ovens, dryers, and heat tunnels adjacent to valve installation points.

Chemical and Pharmaceutical Manufacturing

• Reactor vessel inlet and outlet valve automation in exothermic chemical reactions where heat output creates elevated ambient conditions around installed valve assemblies.
• Distillation column and stripper overhead valve control where elevated process and ambient temperatures are a continuous operating condition throughout the production campaign.
• Pharmaceutical autoclave and sterilizer valve control requiring reliable pilot actuation at temperatures approaching or exceeding 150 F ambient.
• Solvent recovery and high-temperature drying system valve automation where standard-temperature-rated solenoid coils would experience premature failure.

Metals Processing and Industrial Furnaces

• Annealing furnace cooling air and quench valve control, galvanizing line isolation valve automation, and continuous casting cooling water valve pilot control where furnace radiant heat creates elevated ambient temperatures.
• Powder coating oven and industrial dryer valve control for combustion air, recirculation dampers, and conveyor system pneumatic actuators exposed to high ambient heat.
• Forging press and hot metal forming equipment pneumatic actuator control where press-area ambient temperatures exceed standard solenoid coil ratings.

HVAC, Thermal Management, and Building Automation

• Large commercial and industrial HVAC chiller and boiler room valve control where boiler room ambient temperatures during summer operation can exceed standard valve ratings.
• Industrial thermal fluid heater and heat transfer oil system valve automation requiring pilot valves that maintain performance across wide ambient temperature swings.
• Greenhouse and indoor farming climate control valve automation near high-output lighting systems and thermal management equipment.

Ordering and Model Number Configuration

The Automatic Valve D20 Series NAMUR valve uses a structured model number system. The base model number identifies the series, body height, actuation, function, and options. The suffix identifies voltage, coil type, and certifications. Sample model numbers from this series include D2003AAWR-AACT and D2003ACWR-AACT.

High temperature operation requires the CT coil option suffix. Models without the CT suffix use standard coils rated to 123 F (50 C) ambient maximum.

Voltage codes: AA = AC 120V 50/60 Hz, AB = AC 240V 50/60 Hz, DA = DC 12V, DB = DC 24V.

Body height: 03 suffix indicates 1-1/4" body height (D2003 series); 13 suffix indicates 1" body height (D2013 series). Both share 1/4" port size.

The pilot supply is internally supplied at port 1 when pressure is 35 to 150 psig. For external pilot supply, consult factory for ordering code.

Manual override options: Push Non-Locking (standard, blank), Push Turn-Locking (suffix 1), Extended Turn-Locking (suffix 2), No Override (suffix 4).

For G (BSPP) port thread, add G to the model number. Contact Automatic Valve at (248) 474-6761 for configuration assistance.

Accessories

Solenoid Coil Assemblies

Replacement coils are available for all D20 Series NAMUR valve configurations. Standard weather-proof DIN Form B coils (model 7019-9**) are rated to 123 F (50 C) ambient. The high-temperature conduit coil (model 7019-9**CT) is rated to 180 F (82 C) ambient and uses 1/2" conduit connection with 30" leads. Specify voltage when ordering replacement coils.

Warning: Always verify coil temperature rating matches the installation ambient temperature. Installing a standard-rated coil in a high-temperature environment will cause premature coil failure.

Valve Conversion Kits

Valve conversion kits are available to convert between 4-way and 3-way function, change solenoid location (left/right), or convert from internal to external pilot supply. Refer to Automatic Valve's Valve Conversion Instructions document available on the product page for detailed conversion procedures.

Transition Plates

Transition plates (option P in model number) are available to adapt the D2003 NAMUR interface to different actuator mounting configurations. Contact Automatic Valve to confirm compatibility with specific actuator models.

Related Products & Accessories

• NAMUR Valves - Standard Temperature Applications - D20 Series NAMUR valves for standard temperature operation -20 to 123 F, with weather-proof DIN or conduit coils. https://www.automaticvalve.com/series/2986-namur-valves-standard-temperature-applications
• NAMUR Valves - Low Temperature Applications - D20 Series NAMUR valves rated for low temperature operation down to -40 F (-40 C). https://www.automaticvalve.com/series/2987-namur-valves-low-temperature-applications
• NAMUR Valves - CSA/FM Standard Temperature - D20 Series NAMUR valves with CSA/FM explosion-proof certified solenoid coils for hazardous classified areas. https://www.automaticvalve.com/series/2990-namur-valves-csafm-standard-temperature-applications
• NAMUR Valves - ATEX Standard Temperature - D20 Series NAMUR valves with ATEX explosion-proof certified solenoid coils for European hazardous area requirements. https://www.automaticvalve.com/series/2988-namur-valves-atex-standard-temperature-applications
• NAMUR Valves - Intrinsically Safe Standard Temperature - D20 Series NAMUR valves with intrinsically safe solenoid coils for Zone 0/1 and Division 1 hazardous classified areas. https://www.automaticvalve.com/series/2992-namur-valves-intrinsically-safe-standard-temperature-applications
• NAMUR Valves - CSA/FM Low Temperature - D20 Series NAMUR valves with CSA/FM explosion-proof coils rated for low temperature operation down to -40 F. https://www.automaticvalve.com/series/2991-namur-valves-csafm-low-temperature-applications

Frequently Asked Questions (FAQ)

Q: What is the maximum ambient temperature rating for the NAMUR High Temperature series?

A: The high temperature series is rated for ambient temperatures of 0 to 180 F (-18 to 82 C) when specified with the CT (High Temperature Conduit) coil option. This coil uses 1/2" conduit connection with 30" leads and is specifically rated for sustained high ambient service. Standard DIN coils on the same valve body are limited to 123 F (50 C) ambient.

Q: What coil option must I specify to get the high-temperature rating?

A: You must specify the CT coil option suffix in the model number. Models without the CT suffix ship with standard weather-proof coils rated to 123 F (50 C) maximum ambient. The CT coil designation appears at the end of the model number, for example D2003AAWR-AACT.

Q: What is the difference between the D2003 and D2013 body sizes?

A: Both the D2003 and D2013 use the same 1/4" port size and share identical flow ratings of 1.8 Cv (1800 Nl/min). The D2003 has a 1-1/4" valve body height and the D2013 has a 1" valve body height. The appropriate body size is selected based on the actuator NAMUR interface dimensional requirements.

Q: What pilot supply pressure is required for internal pilot operation?

A: Internal pilot supply requires 35 to 150 psig (2.4 to 10.3 bar) at port 1 for 3/2 and 5/2 valve functions. For 5/3 center-position functions, the minimum pilot pressure is 50 psig (3.4 bar). The valve can be field converted to external pilot supply when line pressure does not meet these requirements.

Q: What is the Cv flow rating for the 5/3 function compared to 5/2?

A: The 5/2 single and double solenoid functions have a Cv of 1.8 (1800 Nl/min). The 5/3 three-position functions (closed center, open center, power center) have a slightly reduced Cv of 1.4 (1400 Nl/min) due to the additional spool position and porting geometry.

Q: Can the valve be converted from 5/2 to 3/2 in the field?

A: Yes. The balanced spool construction of the D20 Series allows ports to be plugged for 2-way or 3-way function. Exhaust ports can also be restricted for inexpensive cylinder exhaust speed control. Refer to the Valve Conversion Instructions document available from Automatic Valve for detailed conversion procedures.

Q: Is the manual override standard or optional?

A: Push Non-Locking manual override is standard on all solenoid-controlled D20 Series NAMUR valves. Extended Turn and Turn-Locking override options are available as alternatives. To order without an override, specify suffix 4 in the model number.

Q: What is the enclosure rating of the solenoid coil?

A: The solenoid coil carries NEMA 4X and IP65 ratings, providing dust-tight protection and resistance to water ingress. This makes the valve suitable for outdoor process plant installations and washdown environments even at elevated temperatures.

Q: What does the NAMUR interface standard specify?

A: The NAMUR interface standard, defined by VDI/VDE 3845, establishes standardized dimensional requirements, port locations, and fastening patterns for direct mounting of directional control valves to pneumatic actuators. This standard ensures universal compatibility between compliant valves and actuators from any manufacturer, eliminating external tubing and reducing system installation cost.

Q: What certifications do these valves carry?

A: The D20 Series high-temperature NAMUR valves carry CSA (C22.2/UL STD 429) and Factory Mutual (FM) approval for the solenoid coil assembly, CE marking for EU requirements, and NEMA 4X/IP65 enclosure protection. SAE durability testing to 20 million cycles has been validated for the valve assembly.

Q: Are these valves suitable for use with non-lubricated air?

A: Yes. The D20 Series NAMUR valves are suitable for both lubricated and non-lubricated air service. When used in non-lube service, the Buna-N seals provide adequate lubricity, and no additional air line lubrication is required.

Q: What voltage options are available for the solenoid coils?

A: The D20 Series high-temperature configuration is available in 24 VDC (4.8 W), 12 VDC (5.9 W), 110-120 VAC 50/60 Hz (6.9 VA), 200-240 VAC 50/60 Hz (6.4 VA), and 22-24 VAC 50/60 Hz (6.9 VA). All coils are rated for continuous duty operation.

Q: What is the expected service life of these valves?

A: Durability testing validates 20 million cycles with rust and water injected every 864,000 cycles per SAE specifications. In clean, filtered air service, service life typically exceeds this benchmark. The tapered Tee-Seal self-cleaning design actively maintains seal integrity throughout the valve's service life.

Installation & Maintenance Guidelines

• Mount the valve directly to the pneumatic actuator NAMUR interface per VDI/VDE 3845. Ensure O-rings on the NAMUR interface face are undamaged and properly seated before fastening.
• Torque mounting fasteners to actuator manufacturer specification. Do not over-tighten, as this can distort the valve body or damage O-ring face seals.
• Verify that air supply pressure at port 1 is within the operating range of 35 to 150 psig (2.4 to 10.3 bar) for 3/2 and 5/2 functions, or 50 to 150 psig (3.4 to 10.3 bar) for 5/3 functions.
• For high-temperature installations, confirm that the CT high-temp conduit coil is installed. Do not install standard DIN coils (rated to 123 F) in ambient environments that will exceed that temperature.
• Route conduit wiring using 1/2" conduit from the coil connection point to the junction box. Ensure conduit seal fittings are used where conduit enters the junction box to maintain enclosure integrity.
• Supply filtered air to the valve. Particulate contamination can impair spool movement and reduce service life. A 40-micron or finer filter upstream is recommended.
• For media temperatures below 40 F (4 C), ensure compressed air is dried to a dew point below the minimum operating temperature to prevent ice formation inside the valve.
• When converting to external pilot supply, follow the field conversion procedure in the Valve Conversion Instructions document and verify pilot pressure meets the minimum 35 psig requirement independently of line pressure.
• Test manual override function during commissioning to verify spool actuation and actuator response before connecting to the control system.
• Inspect exhaust ports periodically for contamination buildup. If exhaust flow is restricted, clean or replace the valve to prevent back pressure from interfering with spool positioning.

Warranty & Global Support

Automatic Valve provides a standard warranty on all D20 Series NAMUR valve products covering defects in material and workmanship from the date of purchase. Contact Automatic Valve for specific warranty terms.

Technical support and product configuration assistance is available by phone at (248) 474-6761 or through the Automatic Valve website at automaticvalve.com.

Automatic Valve is a global family member of ROSS Controls, with technical resources and distribution support available throughout the United States and internationally.

For complete technical data, dimensional drawings, operating instructions, valve conversion instructions, and the product catalog for NAMUR Interface Valves, visit the product series page at automaticvalve.com or contact the Automatic Valve team directly.

Product Catalog - NAMUR Interface Valves: https://www.automaticvalve.com/documents/5554/NAMUR_Interface_Valves_AV-NAMUR_en.pdf

Service Instructions - NAMUR Interface Solenoid Valves: https://www.automaticvalve.com/documents/408/NAMUR_Interface_Solenoid_Valves_Service_Form__AV-NAMUR-OI.pdf