All models include special alloy vanes, flange or U.S. TEFC motor, back pressure gauge, gas ballast valve(s), non-return valve, exhaust oil separator(s) with replaceable elements, easy access for exhaust filter element replacement, initial fill of oil. VC models have an attractive sound enclosure provide quiet operation and channels air flow for cooler operation. VC-50 through VC-150 include a standard fine mesh inlet filter screen.
The VC have a fine micro filter or a fine filter on the suction side and on the outlet side an oil and oil mist separator to return the oil to the oil circulation system. The vacuum pump is housed in a sound cover. A fan between the pump housing and the motor provides air cooling. The fan is located in a fan housing that guards against it being touched. The cooling air also flows through an oil cooler. An integral non-return valve prevents the evacuated system from being ventilated after the pump has stopped. If the machine has been idle for more than two minutes the connected pipe should be ventilated to atmospheric pressure. A gas ballast valve fitted as standard prevents condensation of water vapor in the inside of the pump when low amounts of steam are sucked in when the pump is at operating temperature. A reinforced gas ballast can be provided for higher amounts of water vapor. The pumps are driven by standard flanged three-phase motors using a coupling.