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THP 3-Way High Pressure Solenoid Valves

Series THP is a 3-way solenoid valve for all types of nasty chemicals, as well as ultra-pure liquids.
True Blue® diverter or sampling Solenoid Valves Series THP.

Series THP 3-way design:

Diverter or “sampling” valves with no metal parts in wetted area. Design features a non-sticking shaft with an upper and lower diaphragm separating the liquid from opposing springs, plus secondary seals with Fail Dry safety vents. Suitable for virtually all solutions. Series THP is not specifically designed for vacuum service; consult factory if needed.

  • Ultra-smooth, balanced shaft permits use with high backpressures.
  • Bubble-tight sealing.
  • No metal parts in wetted areas.
  • 24 W CE & CSA coil standard with IP65 Enclosure & Lighted DIN Connector.
  • New coil with “COOL DIN” connector uses 75% less energy than previous 20 watt coil
  • 1/4″ & 1/2″ NPT sizes, with variety of orifice sizes.
  • Can be converted to 2-way normally-open or normally-closed if needed.
  • Available in Geon PVC. Elastomer seals in FKM (Viton) or EPDM. Alternate materials available w/quantity orders.

Mode of Operation:

Direct acting; flow is normally through an outlet port, at 90 degrees from the inlet port, on the same plane. When the valve is energized, flow is switched to an outlet port inline with the inlet port, also on the same plane.


Pressure or drain. For vacuum applications, please call our Tech Group at 973-256-3000.


Series THP diverts flow of highly corrosive and ultra-pure liquids. Suitable for virtually all types of corrosive and ultrapure liquids. They do not require pressure to aid in opening the valve.

THP is ideal for sprayhead or filter applications where high backpressures exist.


These True Blue solenoid valves are direct acting. They have an upper and lower diaphragm separating the liquid from opposing springs. They are constructed of Geon PVC with FKM (Viton is a brand name of FKM) or EPDM diaphragms. External fasteners are stainless steel; there are no metals in wetted area.

Available in 1/4″ and 1/2″, the THP has a Cv rating at .31 with a 1/8″ orifice, .52 with a 3/16 orifice, and .61 with a 1/4″ orifice.

Valve performs to 1,000,000 cycles with EPDM diaphragms (FKM or “Viton” diaphragms perform to 100,000 on Series THP). After 1,000,000 cycles (100,000 for FKM), we recommend that the valve be disassembled and inspected. It is also recommended to replace the elastomer seals and u-cups at this point. Contact your distributor for a seal kit. For heavy use applications, you may wish to order a spare seal kit with the valve. Seal replacement takes but a few minutes with common tools; no special training is required.

Pressure considerations:

Inlet and backpressure to 100 psi (4,8 bar) at room temperature (75 F) with smallest (1/8″) orifice. Drops to 70 psi with 3/16″ orifice, and 40 with 1/4″ orifice.

If one of the outlets is plugged to create either a normally-closed or normally-open 2-way valve, the maximum pressure ratings are 40 psi inlet and backpressure.

Coil Info:

A 24 watt IP65 continuous duty coil is standard. When the coil is energized, the valve closes and will remain closed until the coil is de-energized. AC voltages are 24, 120 or 240. 24 volt DC also available; please call our Tech Group at 973-256-3000.

Dimensions, Specifications & Model Numbers:

Dimensions of the True Blue THP 3-way solenoid valve.

Specifications and Model numbers for the classic True Blue three-way solenoid valve

**Model numbers shown with “W24” IP65 coils. With all coils, please specify voltage.

NOTES: Maximum inlet pressure ratings are at full line voltages. Other materials are available; consult factory. The maximum pressure differential is the same as the maximum inlet pressure. 1/8″ and 3/8″ sizes are available in quantity purchases, or we suggest you simply use an appropriate bushing. It is possible to create either a normally-open or normally-closed 2-way valve by simply plugging the appropriate outlet. Pressure ratings in the table are at 75 degrees F (24 C). The THP is not yet represented on our CADlink page. If you need a drawing for your project, we recommend that you right-click the image above, and “save as.”


Additional Info:

Series THP Catalog in .PDF format Click here to download the cut sheet for this valve.

Determining Amperage for a Plast-O-Matic Solenoid Valve This is a technical document in Microsoft Word format that explains how to calculate the amperage required for Plast-O-Matic AC or DC coils.

Overview of the Entire Solenoid Valve Line

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