Air Control Valve A
- Disconnect vacuum hose No. 15 from air control valve A and connect a vacuum pump. Disconnect the air hose between air control valve A and frequency solenoid valve A. Connect a hand vacuum pump and pressure gauge to the hose. See Fig 1 .
- When vacuum is applied to vacuum hose side, air should flow without resistance and the pressure gauge should not register any build up. When vacuum is released, air should flow with resistance and pressure should register on gauge and be released gradually. If air control valve fails either test, replace it.