CAUTION
Gas Filter Rupture upon Excessive Gas Supply Pressure
An excessive supply gas pressure can lead to an overpressure in the detector and can cause the gas filters to rupture. This can pose a health and safety risk.
CAUTION
Escaping Gas
Gas can escape from open gas connections when the detector gas flow and/or the gas supply is turned on. The escaping gas can pose a health and safety risk.
When
Interval for gas filter replacement has expired
Parts required
Gas filter assembly consisting of a charcoal gas filter and a HEPA gas filter
Tools required
Screwdriver, Torx T10
Preparations
Flush the detector with the detector gas flow being turned on. For recommendations on flushing the detector, see Flushing the Detector Between Analyses.
Turn off the pump flow and then the gas flow:
- Turn off the pump flow to the detector. Wait at least 5 minutes. During the waiting period, the detector drains any remaining mobile phase to waste.
- Turn off the gas flow on the detector.
- Wait until the system pressure is down to zero before you continue.
- Turn off the gas supply to the detector.
Turn off the detector with the main power switch.
Follow these steps
With the screwdriver, loosen and remove the top screw on the protective cover for the gas filter assembly.
Slightly loosen the two bottom screws on the protective cover. Leave the two screws attached loosely in the bores. Do not remove the screws.
Push the protective cover upward to release it from the two bottom screws (no. 1 in the image below). Lift the protective cover away from the front panel (no. 2 in the image below).
No. | Description |
|---|---|
1 | Top screw on protective cover |
2 | Protective cover |
3 | Bottom screws (slightly loosened) |
4 | Gas filters |
The gas filters are uncovered now:
No. | Description |
|---|---|
1 | Charcoal gas filter |
2 | Elbow fittings |
3 | HEPA gas filter |
4 | Gas filter clamps |
Disconnect the gas filter assembly from the gas connectors on the detector:
- On the two (push-in) elbow fittings on the detector gas connectors, push in the locking ring on each elbow fitting (no. 1 in the image below) and keep pushing it while performing the next step.
Leave the elbow fittings connected to the gas filter assembly. - Pull the two elbow fittings off from the gas connectors on the detector (no. 2 in the image below).
Pull the gas filter assembly out of the clamps.
With the new gas filter assembly, mind the correct orientation for the gas flow for installation. Observe the flow direction signs on the filters.
The bottom gas filter must be the charcoal gas filter (thick black inner filter cylinder; no. 2 in the image below).
The top gas filter must be the HEPA gas filter (thin white inner filter cylinder; no. 1 in the image below).
Push the new gas filter assembly into the clamps observing the orientation signs for the gas flow on the gas filters. See image below.
Push the (push-in) elbow fittings into the gas connectors on the detector. Check that the connections are secure: Slightly pull on the fittings. If a fitting slides out, repeat this step.
Install the protective cover: Hold the protective cover onto the interior panel. Slide it downward carefully so that the bottom screws match the recesses.
With the screwdriver, tighten the three screws on the protective cover.
Turn on the detector with its main power switch.
In Chromeleon, consider updating the Predictive Performance information for the gas filter assembly.
Turn on the gas flow. See Turning On/Off the Detector Gas Flow.
No. | Description |
|---|---|
1 | HEPA gas filter |
2 | Charcoal gas filter |