Replacing a Differential Pressure Switch

Procedure

1. Tap Shutdown on the home screen of the controller. Turn off the active power switch QF1 and standby power switch QF2 (you do not need to turn on the standby switch QF2 for the model with a single power supply), and drive switch QF3.

   Exercise caution because the device is still energized after it is shut down on the controller home screen.

2. Open the rear door and remove the air filter.
3. Remove the pressure inlet tube, as shown by (1) in Figure 6-7.
   Figure 6-7 Removing a differential pressure switch
   

4. Use a Phillips screwdriver to remove the screws on the top cover of the differential pressure switch and cable screws, as shown by (2) in Figure 6-7, and remove the cables.
5. Use a Phillips screwdriver to remove the four screws, and remove the differential pressure switch, as shown by (3) in Figure 6-7.
6. Set the new differential pressure switch to 250 Pa.
   Figure 6-8 Setting values for a differential pressure switch
   

7. Install the new differential pressure switch and the pressure tube, and connect the cables.
   Figure 6-9 Installing a differential pressure switch
   

8. Install the air filter and close the rear door.
9. Power on the device and tap Start on the home screen. Ensure that the smart cooling product is running properly without any alarms.