ASCO Valve - FAQ Product Questions

Frequently Asked Questions

Product Questions

Q: How do you wire a Red-Hat II valve (3 wire coil)?
Q: Are ASCO 2-way valves bi-directional?
Q: What is the difference between Red Hat versus Red Hat II valves?
Q: Why does the catalog limit the minimum ambient temperature to 32°F on most general purpose valves?
Q: How much back-pressure can an ASCO 2-way valve hold?
Q: Can you change the operating voltage on an ASCO valve from A/C to D/C or vice versa by changing the coil?
Q: What is the difference between a direct acting valve and a pilot operated valve?
Q: What is the definition of minimum and maximum operating pressure differential?
Q: What is the flow path of a valve, and how do I pipe it up?
Q: Are ASCO valves 'CE' marked?
Q: Where is the voltage identified on the ASCO valve?
Q: Can any of the ASCO Pneumatic valves be manifolded or ganged together?
Q: What are the operating pressure and flow limits on ASCO Pneumatic valves?
Q: How do you wire the DIN connector on the ASCO Pneumatic valves?
Q: Are ASCO Pneumatic valves bi-directional?
Q: Can ASCO Pneumatic valves be used in a vacuum service application?
Q: I work with valves that meet A.N.S.I. standards and the ports are designated with letters, but your port designations are numbers, why?
Q: How do I pipe up the valve ports on ASCO Pneumatic valves?
Q: What is the advantage of using the ISO Series valves?
Q: Are ASCO Pneumatic valves products direct acting?
Q: Can I get the CE mark on ASCO valves?
Q: The only catalog available for cylinders seems to be the NFPA cylinder catalog. Are these the only type of cylinders available?
Q: Do you offer air preparation equipment?
Q: What port sizes and flows are available on your air preparation equipment?
Q: Who should I contact for price and/or delivery for ASCO products?
Q: Can I convert from normally open to normally closed and vice versa?
Q: I have a serial number, can you tell me the valve number and/or voltage?
Q: I have an ASCO valve with no label/nameplate. Can you tell me what it is?
Q: I have an 8290 series valve. Can I switch from normally open to normally closed by switching the pilot port?
Q: I have a valve and I want to add a manual-operator. Can this be done?
Q: Can I purchase a replacement diaphragm or spring, or do I need to purchase the entire rebuild kit?

Q: How do you wire a Red-Hat II Valve (3 wire coil)?
A: All ASCO AC/DC coils are suitable for continuous duty except where otherwise noted and are single phase.
1. RedHat II coils have 3 wires - 2 wires of the same color (i.e., red or yellow) and 1 wire green with a yellow stripe which is an external ground wire. Since ASCO coils are not polarity sensitive, connect the 2 wires of the same color to the positive and negative power supply, the green/yellow stripe wire to ground.
2. For three-phase systems, the 2 wires of the same color can be connected to any of the three phases.
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Q: Are ASCO 2-way valves bi-directional?
A: ASCO 2-way valves are not bi-directional. They are designed for flow in one direction only. Reversing the flow may result in the inability of the valve to shut off, or other unreliable or erratic operation.
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Q: What is the difference between Red Hat versus Red Hat II valves?
A: The Red Hat II solenoid utilizes a one piece epoxy molded design, which meets enclosure type 1, 2, 3, 3S, 4 & 4X ratings.

The Red Hat design utilized a coil housed inside a metal enclosure which meets enclosure type 1 rating only. Other enclosure ratings for Red Hat solenoids are available as options.

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Q: Why does the catalog limit the minimum ambient temperature to 32°F on most general purpose valves?
A: Since 32°F is the freezing temperature of water, any moisture in the media would solidify causing the valve to stick. In addition, as temperatures decrease, elastomers can harden to the point where valves may leak.
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Q: How much back-pressure can an ASCO 2-way valve hold?
A: The standard catalog 2-way ASCO valves are not designed to hold back pressure. Back pressure occurs the downstream pressure exceeds the inlet pressure. This may result in the inability of the valve to close. Consult the factory if you have a specific back-pressure requirement.

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Q: Can you change the operating voltage on an ASCO valve from A/C to D/C or vice versa by changing the coil?
A: Generally, ASCO valves cannot be changed from A/C to D/C or vice versa due to the difference in solenoid designs. Voltages can be changed within the same current type (e.g., 120/60 to 240/60 or 12/DC to 24/DC) by changing the coil.
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Q: What is the difference between a direct acting valve and a pilot operated valve?
A: In a direct acting valve, the solenoid core directly opens or closes the orifice, depending upon whether the solenoid is energized or de-energized. The valve will operate from zero psi to the rated maximum pressures.

A pilot operated valve has a pilot and bleed orifice and utilizes line pressure for operation. When the solenoid is energized, the core opens the pilot orifice and relieves pressure from the top of the valve piston or diaphragm to the outlet side of the valve. This results in an unbalanced pressure, lifting the piston or diaphragm off the main orifice. When the solenoid is de-energized, the pilot orifice is closed and full line pressure is applied to the top of the piston or diaphragm, closing the valve.

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Q: What is the definition of minimum and maximum operating pressure differential?
A: Minimum operating pressure differential is that which is required to open the valve and keep it open. For 2-way valves, this is the pressure difference between the inlet and outlet ports. For 3-way and 4-way valves, this is the pressure difference between the pressure and exhaust ports.
The maximum operating pressure differential refers to the maximum difference in pressure between the inlet and outlet against which the solenoid can safely operate the valve.

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Q: What is the flow path of a valve, and how do I pipe it up?
A: Flow paths are the direction that a media must travel through the valve in order for it to function properly. They vary from valve to valve and piping instructions, as shown in the Installation and Maintenance instructions supplied with every valve, should be carefully followed.

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Q: Are ASCO valves 'CE' marked?
A: All ASCO Red Hat II valves currently being manufactured have the 'CE' mark stamped on the coil.
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Q: Where is the voltage identified on the ASCO valve?
A: On Red Hat II products, the voltage is stamped on the coil with an ink stamp on all Red Hat II valves. The stamp is located on the flat side of the coil opposite the electrical connection. On Red Hat products, the voltage is printed on the label affixed to the coil housing. In addition, the voltage is ink stamped on the coil itself.

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Q: Can any of the ASCO Pneumatic Controls valves be manifolded or ganged together?
A: Yes, many of our valves are designed to be manifolded or ganged together.
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Q: What are the operating pressure and flow limits on ASCO Pneumatic Controls valves?
A: It depends on the valve, but the maximum pressure can range from 115 psi on some of our 5/2 valves up to 575 psi on some of our 3/2 valves. Pilot operated valves have a minimum pressure requirement from 25-45 PSI, depending on the valve. Some pilot operated valves can be externally piloted if the minimum pressure requirement cannot be met. The flow factors (Cv) can range from .001 to 12.5*.
*Does not include 8290 series valves.

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Q: How do you wire the DIN connector on the ASCO Pneumatic valves?
A: Generally, the #1 and #2 pins are connected to the voltage supply. The coils are not polarity sensitive. The ground doesn't have to be utilized unless the application requires it.

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Q: Are ASCO Pneumatic Controls valves bi-directional?
A: Some of them can be used in a bi-directional mode, but not all. See vacuum service below.
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Q: Can ASCO Pneumatic valves be used in a vacuum service application?
A: Some valves can be used with vacuum, some cannot. Those that can be will be catalogued with a minimum pressure of 29”Hg. Valves designated in our catalog with a pressure range starting at 0 psi or with a minimum pressure (e.g., 25, 30 or 45 psi) can not be used with vacuum. Valves that can be externally piloted may be used in vacuum applications when properly configured and supplied with external pressure that meets minimum pressure requirement.

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Q: I work with valves that meet ANSI standards and the ports are designated with letters, but your port designations are numbers, why?
A: Not all of our valves are numbered. Some of our valves are lettered P for pressure inlet, C for cylinder, and E for exhaust. Some of our valves are designed per the ISO standard in which the ports are numbered per the following:
-Port 1 is the inlet.
-Ports 2 and 4 are the cylinder or working ports.
-Ports 3 and 5 are the exhaust ports of the cylinder ports where as 2 exhausts to 3 and 4 exhausts to 5.

Due to the various marking conventions used on different product types, it is important to refer to the specific catalog sheets and/or Installation & Maintenance instructions for a given valve product.

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Q: How do I pipe up the valve ports on ASCO Pneumatic valves?
A: Typically, Port 1 is inlet* or supply pressure; Ports 2 & 4* are the work ports; Ports 3 and/or 5* are the exhaust ports.
*In special applications this might not always be true. Please refer to catalog sheets and/or Installation & Maintenance instructions.

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Q: What is the advantage of using the ISO Series valves?
A: The 5/2 and 5/3 ISO Series valves conform to the ISO valve to subbase interface. If a customer needs a replacement and is using another manufacturer's ISO 1 valve, one of our ISO 1 valves will bolt right into place.
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Q: Are ASCO Pneumatic valves products direct acting?
A: Some of our small 2-way and 3-way valves are direct acting, but our larger 2/2 and 3/2 and all of our 4-way valves are pilot assisted.
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Q: Can I get the CE mark on ASCO valves?
A: Most of our valves are CE marked.
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Q: The only catalog available for cylinders seems to be the NFPA cylinder catalog. Are these the only type of cylinders available?
A: ASCO no longer offers NFPA cylinders and the NFPA cylinder catalog is inactive. We do offer a number of different European series cylinders that conform to ISO, CETOP, AFNOR or combinations of them. Please contact us if you have non-European or non-NFPA cylinder requirements.

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Q: Do you offer air preparation equipment?
A: Yes, we recently launched our Modulair 100 Series air preparation equipment which is totally modular.
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Q: What port sizes and flows are available on your air preparation equipment?
A: All the way from 1/8" to 1" ports and flows range from 19 cfm to 600 cfm in their respective series.
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Q: Whom should I contact for price and/or delivery for ASCO products?
A: Click here » CONTACT
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Q: Can I convert from normally open to normally closed and vice versa?
A: For 2-way valves, no. 3-way valves listed for universal operation can accommodate either form of operation. Please refer to catalog sheets and/or Installation & Maintenance instructions.

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Q: I have a serial number, can you tell me the valve number and/or voltage?
A: Click here » CONTACT
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Q: I have an ASCO valve with no label/nameplate. Can you tell me what it is?
A: ASCO manufactures thousands of different valve constructions. Without the nameplate information provided with the valve, it is extremely difficult to identify the exact construction. It is best to select an appropriate valve from our current catalog as a replacement. Create link to on-line catalog.

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Q: I have an 8290 series valve. Can I switch from normally open to normally closed by switching the pilot port?
A: No, the operator is designed specifically for normally open or normally closed operation and cannot be changed in the field.

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Q: I have a valve and I want to add a manual-operator. Can this be done?
A: No, there are no manual-operator kits available to upgrade solenoid valves in the field.
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Q: Can I purchase a replacement diaphragm or spring, or do I need to purchase the entire rebuild kit?
A: ASCO does not sell individual replacement parts. We only sell these items as part of a complete rebuild kit. Rebuild kits contain all of the parts that are subject to wear as well as detailed installation instructions.

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For more information
Write: ASCO, 50 Hanover Road, Florham Park, NJ 07932
Tel: 800-972-ASCO or 973-966-2000
Fax: 973-966-2448
Email: info-valve@asco.com

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