General
For many product lines there are multiple options, features, and/or characteristics that need matched to the project requirements. Our greatest fear at VSI is that a customer ends up with a product that isn't their solution. Please give us a call or send us an email and we will be glad to offer you a no obligation quote. Combined with our extensive knowledge, we're likely to save you significantly over competitor's internet prices.
VSI has over 75,000 sqft of warehouse space where we keep an exhaustive inventory. Many items can ship in 3-5 days time typically. If your order contains custom machined linkages please allow up to two business weeks. Proposals with custom material valves/actuators will be given specific delivery estimates with the proposal. Orders may be expedited at additional cost, please inquire with your sales associate.
In general no, VSI will work with any supply house, reseller, OEM, or end user. In some states or countries VSI has exclusive distributor agreements, please visit our Contact page for details.
Of course! Please contact VSI and we would be glad to schedule a tour of any of our facilities located in Alpharetta, GA just north of Metro Atlanta.
We certainly think so, and you will too. Our warehouse and processes are fully ISO 9001:2015 certified and all valves and actuators are 100% tested before shipment. We utilize top quality test equipment from world class manufacturers such as Progetti P.C. as well as specifically designed and in-house built specialty test equipment where necessary. Many of our designs are third-party design qualified/tested as well. We offer a robust warranty and if required can even offer bonding on projects where required.
Actuators
24VAC actuators have advantages in ease of installation and interconnection with existing systems, but they also have their drawbacks. The total motor power must be the same to actuate a given valve size; this means according to the Power Equation P=VI reducing the voltage(V) results in an increase in current(I). This high current necessitates larger more expensive and complex control components within the actuator. Additionally, low voltage sources are more subject to voltage drop across wiring making them unsuitable for use where the power lines must be ran a large distance.
Besides the obvious fact additional cost comes from the mechanical spring, the motor and gearing must be sized larger to counteract the spring force in the motor drive direction. With a spring return unit, as the motor is driving the valve it must overcome not only the torque of the valve but also the spring loading force. As a rule of thumb the motor size has to be doubled on spring return actuators.
Two position actuators run fully between open and closed position. An example would be a spring return unit with two wire control. When power is applied the actuator runs fully open and then stops, when the power is removed the actuator runs fully closed. A floating actuator is capable of stopping mid-position for throttling flow, typically with three wire control. Floating actuators are a good economical alternative to fully modulating actuators for systems with infrequent adjustments of flow may be necessary.
Valves
The short answer is yes. However many factors should be considered to determine if it is more economical or feasible to replace the valve. Some products such as the Series 2100 require special equipment to disassemble, and VSI's competitive costs makes it logical to completely replace the valve. Other valves such as the Series V can be readily serviced in the field with common hand tools and lend themselves to being rebuilt.
The stem of all VSI valves are machined or etched with a groove. This groove will be parallel with the pipe when the valve is open.
Equal percentage valves have a flow that increases progressively more as the valve opens, at a rate greater than linear. Opening from 0% to 10% the flow may be only a few percent of the capacity of the valve, however opening from 90% to 100% the flow can change as much as 50% of the capacity of the valve. When installed in systems with pumps, chiller, or heating coils, the equal percentage characteristic of the valve is countered by the decreasing characteristics of the rest of the equipment creating a system that is linear to the input of the valve; ie a 10% change in the valve position will result in a 10% temperature change.
