Troubleshooting - Hach BODTrak II Basic User Manual

C A U T I O N
Chemical exposure hazard. Obey laboratory safety procedures and
wear all of the personal protective equipment appropriate to the
chemicals that are handled. Refer to the current material safety data
sheets (MSDS) for safety protocols.
Clean the instrument
Clean spills on the instrument with a soft cloth that has been dampened
with deionized or distilled water.
Clean the sample bottles
Clean the sample bottles and caps with a brush, water and a mild
detergent. Flush the containers with fresh water followed by a distilled
water rinse.
Clean the stir bars and seal cups
Clean the stir bars with hot water and soap. Use a brush to remove
deposits. Rinse with fresh water and then rinse with distilled water.
Carefully empty and rinse the seal cups with water. Invert to dry.
Storage
The bottle fences prevent tipping of the bottles and provide tubing
management in storage. For storage, put the tubing in the opening in the
bottle fence. Move the tubing counter-clockwise and secure the bottle
cap inside the fence.

Troubleshooting

Incorrect BOD curves
Figure 4 shows incorrect BOD curves for a 10 day test period. For typical
curves, refer to Typical curves on page 7.
10 English
Figure 4 Incorrect curves
1 High oxygen demand
2 Nitrification
3 Excessive time lag
4 Initial sample temperature below
20 ºC or supersaturated with
oxygen
5 Bottle leak