15 Maintaining a Valve
To Replace a Rotary Valve in the Valve Box
234 Maintaining Your GC
11 Use needle-nosed pliers to move the valve rotor index pin of the valve counterclockwise
until the pin touches the valve stop Off position.
12 Plumb the new valve using the existing fittings.
Hazardous sample gases may be present.
13 Turn on the carrier and sample gases, then check for leaks at the valve fittings.
• Using the needle-nosed pliers to toggle the valve, check both the On and Off positions.
• When leak free, set the valve to Off. See step 11.
14 Install the upper valve box assembly. See “To Install the Upper Valve Box” on page 237.
15 Perform an inlet Leak & Restriction test and reset the maintenance counters.
Valve rotor index pin
Valve stop Off position
1. Sample in
5. Carrier gas in
4. Column
2. Sample out