RKI Instruments Portable Gas Monitor GX-3R

Remove the rubber boot from the GX-3R

Peel off the old buzzer cover located between the AIR and POWER MODE buttons

Is there any residue remaining on the case?

Clean any remaining residue from the case if necessary

Peel the backing off of the new buzzer cover

Install the new buzzer cover between the AIR and POWER MODE buttons

Unscrew the two screws holding the bottom cover

Pry each side of the bottom cover away

Remove the white hydrophobic filter

Install the new hydrophobic dust filter

Reattach the bottom cover to the GX-3R

Reinstall the two screws that were loosened in Step 3

Use a small Phillips screwdriver to unscrew the two screws holding the bottom cover

Using a small flat blade screwdriver, gently pry each side of the bottom cover away from the rest of the GX-3R’s case

Remove the bottom cover from the rest of the GX-3R’s case

Remove the filter gasket/sensor retainer assembly

Enter Gas Select Mode and navigate to GAS COMB

Press AIR to scroll to GAS COMB

Select and change target gas for a channel

Press and release POWER MODE to display the first channel

Press AIR to scroll to the desired instrument channel

Press and release POWER MODE to select the channel

Press and release POWER MODE to save the setting

Verify the instrument returns to the channel selection screen

Change the target gas or turn the channel off

Ensure all necessary equipment is available

Confirm the regulator knob is turned all the way clockwise and attach it to the calibration cylinder

Install the calibration cup onto the GX-3R ensuring correct orientation

Connect the tubing from the regulator to the inlet of the calibration cup

Press AIR to scroll to GAS TEST in Maintenance Mode

Press and release POWER MODE to display current gas readings

Turn the regulator knob counterclockwise to open the regulator