Thermo Scientific FTIR, User Manual

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Maintenance
Replacing the rear filter
How often you need to replace your heated filter depends on your specific use and sample gases.
One indication that you need to replace the filter is a noticeable decline in the flow of the sample gas
entering the system. Replace the filter if more than 70% of the filter has changed color.
Before you begin, disconnect or turn off the sample gas connected entering the system.
For replacement filters or other parts, contact technical support.
CAUTION
Avoid burn hazard. The filter assembly becomes very hot during reg-
ular operation. Before replacing the filter, turn off the heater and allow
the filter assembly to cool to room temperature.
❖
To replace the optional heated filter
1. Ensure that the heaters and vacuum pump switches are in the off position. Use the main power
switch on the back of the Heated Valve Drawer to turn off the entire system.
2. To remove the filter assembly, press the black handle in and turn counterclockwise about 5
degrees. It takes about 3 to 5 pounds to overcome the spring.
64 Modular Gas System User Guide Thermo Scientific