There are two models of Edstrom Drinking Valves available - the new Edstrom Vari-Flo Valve and the Edstrom Original Valve. Both models are designed to operate using the patented pivoting stem valve mechanism. You should select the valve that best suits your application.
The Vari-Flo valve is precision machined from solid brass and is available with either 1/8 inch mpt for PVC pipe system or 3/16 inch barb for Flex-Tube system connections. The small diameter of the stainless steel stem that the animal must move to release water and the low force required to move it makes this valve ideal for use with even the smallest of creatures, such as weanling mice and finches.
The Vari-Flo valve is available with a 3/16" barb connection (part number 1000-8000) for use with Valve Clip part number 1100-7440 or with a 1/8" male pipe thread connection (part number 1000-8010) (see diagram below). The rate that water is discharged from the Vari-Flo Valve can be adjusted over a wide range to best suit your animals and reduce the spillage of water into the cage as the animal drinks. The rate can be adjusted from a slow trickle, 20 cc per minute, to a strong stream, 100 cc per minute.
This drinking valve is slightly larger than the Vari-Flo, with thicker materials of construction which make it the preferred valve for use with larger gnawing animals (i.e. rabbits, chinchillas). This valve is made from solid brass. Both models have choice of connections style: 1/8 inch mpt or 3/16 inch barb.
The Original valve is available with a 3/16" barb connection (part number 1000-0766) for use with Valve Clip part number 1100-0867-100 or with a 1/8" male pipe thread connection (part number 1000-0768) (see diagram below).
Look Inside the Valve - rugged, simple design
Exploded view of the Edstrom Vari-Flo Drinking Valve
The pivoting stem design used in all Edstrom valves is easy to understand when you look at the cross-sectional drawings of the valve below.
In the normal, closed position, the head of the stem is held securely against the O-ring by the elastic diaphragm, preventing water from flowing under the stem head and out the valve.
When the end of the stem is moved in any direction by biting, licking or pecking, the head of the stem pivots on the O-ring. One side of the head lifts off the O-ring and allows water to flow under it and out to the animal's mouth or beak.
When the animal releases the end of the stem, the elasticity of the silicone rubber diaphragm located behind the stem head pushes the head back to the closed position, stopping the flow of water.
The many advantages and benefits of this simple valve design.
Local plumbing codes may require that you install an Auto-Air Break Valve at the point you connect your automated watering system to your domestic water supply. Use an approved device for this purpose.