Services > Knowledge Base
On my handheld Spirometer the display is showing the message C21.
Example C21
It is a rare occurence for Micro Medical Handheld Spirometers to show C21 on their display screen (see above example). What the C21 display message means is that the Handheld Spirometers needs to be calibrated.
The cause of this rare problem is due to the handheld unit losing it's calibration setting. To resolve this problem you need to contact our service department as the unit will need to be returned for factory calibration
Contact Us
By email: service@micromedical.co.uk
By FAX: +44 (0) 1634 893600
By Phone: +44 (0) 1634 899113