4104 Series Pressure & Vacuum Regulators
U.S. Patent No. 4,315,520
Airtrol 4104 series pressure and vacuum regulators are designed for applications requiring very low output settings and low flow. Full scale ranges as low as 1.5 psi pressure and 3″ Hg vacuum are available. Settings as low as 1″ WC are easily maintained with both. Both units will also accept a pilot input, allowing pneumatic control of the output setting (see schematics). Hysteresis free adjustments are made through a non-rising stem, available with an attractive knob, plain (to allow the installation of OEM knobs) or flush for “back panel” applications.