Viking Model VXR Dry Pipe Valve, 2-1/2 in to 6 in, 250 psi

An externally resettable dry pipe valve rated to 250 psi

The Viking Model VXR is an externally resettable, latching, differential dry pipe valve. Its clapper seals the air or nitrogen pressure in the sprinkler piping. When that pressure falls far enough to overcome the differential, supply water lifts the clapper and fills the system. The clapper is reset with a push rod on the bottom of the valve body, so the cover does not need to come off for a normal reset. Viking states the valve has been available since 2022.

Compared with the older Model F-1, the VXR carries a higher water working pressure of 250 psi, is lighter and covers 2-1/2 in sizes. The valve operates a water motor alarm and an electric pressure alarm switch, and the Model D-2 accelerator can be added for large systems.

Technical specifications

The part numbers above are for the valve only. Trim is covered in a separate Viking VXR dry system risers data page.

Selection and maintenance points

Choose the VXR where the water supply pressure goes above the 175 psi limit of the F-1, where a compact lighter valve eases riser design, or where the external reset is a benefit for testing. Hydraulic calculations should use the friction loss shown for the size, and the Cv factor helps when modelling the riser.

Viking states that the hand hole cover is stainless steel with E-coat, that fastener torques are listed in Table 3 of the data page and that the clapper rubber and seat should be inspected for cracking, cuts and deep grooves during maintenance. Several moving parts have replacement kits marked in the parts table.

The VXR must be trimmed to the Viking VXR dry system risers data page and installed in the vertical position. Air or nitrogen supplying the system must be clean, dry and oil free, and Viking recommends an air maintenance device on each system with an automatic supply, as required by NFPA 13. System pressure must never exceed 65 psi (4.5 bar) with the clapper closed. Flush the water supply piping before installation so that no foreign matter reaches the seat, and keep the valve in an area free of freezing temperatures and physical damage, using a heated valve house if required. Where corrosive atmospheres or contaminated water are present, the owner has to verify compatibility with the valve.

Related Viking valves

More fire protection items are in our Fire Fighting equipment range.

Confirm before ordering

Confirm size, end connection and trim package, since the valve part numbers listed do not include trim. Check the supply pressure, the system volume, the accelerator choice and the approvals the project demands. The attached Viking technical data lists the components and materials. Send size and quantity for a quotation.

How the Viking Model VXR works

The clapper holds the water back while the sprinkler piping is full of air or nitrogen. When a sprinkler opens, the air pressure falls. At the differential point the supply water lifts the clapper and fills the system. Water then flows to the alarm devices. A push rod on the bottom of the body resets the clapper.

Where the Model VXR is used

• Dry sprinkler systems
• Unheated buildings
• Systems with a high water supply pressure
• Compact risers
• Systems with a water motor alarm

Selection checklist for the Model VXR

• Valve size
• Water supply pressure
• Riser space
• Alarm devices
• Accelerator need
• Trim package
• Friction loss
• Part number

Installation, commissioning and maintenance notes for the Model VXR

Install the valve in the riser with the flow arrow in the right direction. Fit the trim from the separate riser data page. Set the air or nitrogen pressure. Test the alarms. Reset the clapper from outside with the push rod.

Requesting a quotation for the Viking Model VXR

Please send the valve size, the trim you need and the system pressure. Seven Star LLC serves industrial customers in Oman and the GCC and replies with a quotation based on the information provided.

Model VXR valve type

It is a differential dry pipe valve.

Model VXR reset

It resets externally with a push rod.

Model VXR sizes

The sizes are 2-1/2, 3, 4 and 6 inches.

Model VXR working pressure

The water working pressure is 250 psi (17.2 bar).

Model VXR pressure differential

The air to water differential is about 5.75 to 1.

Model VXR part numbers

The valve-only numbers are 24047, 24065, 24068 and 24069.

Model VXR friction loss

The friction loss is 11, 14, 21 and 29 ft of pipe.

Model VXR Cv factor

The Cv factors are 159, 250, 409 and 1009.

Model VXR weight

The shipping weight runs from 11.8 kg to 48.5 kg.

Model VXR body

The body is ductile iron.

Model VXR seat

The seat is brass.

Model VXR clapper

The clapper is PTFE coated ductile iron.

Model VXR alarms

It operates a water motor alarm and an electric pressure alarm switch.

Model VXR accelerator

A Model D-2 accelerator can be added for large systems.

Model VXR compared with the F-1

It has a higher pressure rating than the older F-1 and is lighter.

Model VXR colour

The colour is black.

Valve records for the Model VXR

Record the size, the part number and the alarm test results.

Choosing the right Model VXR size

Choose the size from the riser design and the hydraulic calculation.