Now your customers can have:

             The Smart VOV was successfully tested for over two years in the 
             desert in severe use vehicles (for more than 2,000,000 miles).
             U.S. automakers are proving the Smart VOV as a replacement
             for the orifice tube.

Tech talk - how it works

The Smart VOV (variable orifice valve) uses system pressure and refrigerant flow to move a metering piston relative to a fixed opening in the sleeve. The piston movement is resisted by an attached spring.

When idling at high ambient temperatures, the piston shifts to a smaller metering area similar to a TXV. This compensates for the reduced compressor output and increases the cooling performance. The Smart VOV also has a unique re-open feature which reduces compressor pressure for severe idle conditions.

At highway speeds, the Smart VOV operates on a large orifice. The net result is better performance than a TXV without the complexity or reliability concerns.

Unlike a TXV, which has constantly moving parts and small internal clearances, the Smart VOV is stationary during most operating conditions and has large internal clearances. Its low friction floating design insures smooth operation and extremely long life.


Nartron Corporation | Reed City, Michigan | 231-832-5525

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