Removal and replacement procedures 23
Drain pan sensor
The HP POD 40c NA includes six heat exchanger condensate drains. One drain pan sensor is located in the
drain tray below each set of heat exchangers.
Two sensors are also located in the header drain pans, one in cooling zone 2 and one in cooling zone 5.
The normally-open circuit is closed when the probes of the drain pan sensor become wet, which allows 24
VDC to travel back to the ECS panel and trigger the alarm.
You need a screwdriver for installation.
Removing the drain pan sensor
1.
If you are removing a heat exchanger drain pan sensor, do the following:
a.
Inspect the area by removing the center, bottom fan from the center fan bank in the associated zone.
For more information, see "Removing the fan."
b.
To gain additional working space, you might need to remove a fan bank in the associated zone. For
more information, see "Removing the fan bank."
2.
Follow the sensor wire to the associated satellite box. Disconnect the wire from the satellite box terminal
and note the wire location.
Heat exchanger drain pan sensor
-or-
Header drain pan sensor
3.
Pull the wire through from the satellite box to the sensor location, and then remove the sensor.
