Humidity Sensor (Hs); Checking The Operation Of The Humidity Sensor - Carrier Transicold 69NT40-561-001 Operation And Service Manual

2. Rotate the gear clockwise until it stops.
3. Rotate the gear 1/4 turn counterclockwise.
4. Carefully reposition the slide onto the air makeup panel, given that the gear is engaged with the rail and has
not moved.
5. Position slide panel to the fully closed position.
6. Cd45 will automatically be shown on the left display.
7. Depress the ENTER key and hold for five seconds. CAL for calibration is displayed.
8. Depress the ALT MODE key on the keypad and hold for five seconds.
9. When calibration has been completed, Cd45 causes 0 CMH/CFM to be shown on the right display.
10. Secure the air makeup panel slide to the unit with the two nuts; stake threads.

7.26 Humidity Sensor (HS)

The humidity sensor (HS) is an optional component that allows setting of a humidity setpoint in the controller. In
dehumidification mode, the controller will operate to reduce internal container moisture level.
7.26.1

Checking the Operation of the Humidity Sensor

This procedure is to be performed in an effort to ease the troubleshooting of the humidity sensor. When performing
this procedure and while working on the unit, always follow the proper lockout/tagout procedures.
Items Required:
• One 7/16" socket wrench or nut driver.
• One 1/4" socket wrench or nut driver.
• One clean, clear water bottle with a minimum 6 cm (2.5 in) opening and capacity to hold 500 ml (16.9 oz).
• 100 ml (3.4 oz) of fresh water - distilled if available.
• 50 gm of Salt (NaCl).
Procedure:
1. Remove the left Upper Fresh Air Makeup Vent panel.
2. Remove the humidity sensor from the mounting hardware and bring to the front of the access panel.
3. Disconnect the humidity sensor from the harness.
4. Drill a 3 cm (1.25 in) hole in the cap of a bottle.
5. Pour approximately 100 ml (3.4 oz) of water into the empty clean bottle.
6. Add salt to the water until it is present at the bottom of the bottle.
7. Cap the bottle and tape over the drilled hole.
8. Shake the bottle until the salt dissolves and water is saturated.
To ensure saturation, add additional salt until it settles at the bottom without dissolving while shaking.
9. Remove the cap and insert the humidity sensor into the bottle through the bottle opening and pull the connector
back through the drilled hole in the cap. Then, secure the cap and seal the wire going through the cap.
T-340
NOTE
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