Frequently Asked Questions

This means the humidity sensor needs to be recalibrated. If the unit is less than 12 months old (from the date of purchase), send it back to NK for recalibration under warranty. If the unit is more than 12 months old, it can be returned to NK for recalibration for $40 plus shipping, or can be calibrated in the field using the NK RH Calibration Kit.

This means that the RH was not calibrated(same as E2). This will appear on screens that rely on RH calculations.

This means that the battery is running low. Replacing the battery will resolve this issue.

This message means that your batteries interfered with compass calibration. To solve this issue insert battery shim, rotate batteries, and try again. If this condition persists, try using a different battery brand. NK recommends Made in the USA Energizer® Brand Ultimate Lithium AAA batteries for improved reliability, capacity, cold-weather performance and weight.

Turn on your unit and remove the impeller. Find a magnet, such a refrigerator magnet. Go to the wind screen and move the magnet in the empty impeller area. If you get numbers other than “0” or “--", the unit is fine and you just need a new impeller. Call 610-447-1555 or visit the Kestrel® replacement parts page for a replacement impeller. On the other hand, if you still only get “0” or “--", please send the unit in for repair.

The unit is probably picking up electro-magnetic fields from elsewhere (i.e. nearby computer, TV, or electric motor). Simply remove the electro-magnetic source.

First, make sure the unit is ON. The Kestrel must be ON in order to record any measurements related to Globe Temperature(TWL, WBGT, TnWB). If your unit is ON and you are still reading *** on the Kestrel measurement screen, there may be an issue with your black globe, and it may need to come in for repair. Contact us at Techsupport@nkhome.com or 1-800-784-4221.