5 years after the date of initial use. For the 01893 and 01894 wall units, you only need to replace the actual sensor after 5 years, using the 01893.G replacement sensors (for LPG) and 01894.M (for natural gas).

Yes, paying careful attention to the polarity of the terminals.

No. All Vimar gas detectors are calibrated and sealed at the factory according to the values​prescribed by CEI-UNI-CIG 70028 regulations. In the case of false alarms, you must first check if the detector is installed in the correct position and according to the product instruction manual. For detectors that have been installed for some time, check the expiry date written on the front of the unit; it is fixed at 5 years after initial activation. If the date has been exceeded, you need to replace the device (you can replace the sensor in the wall mounted types only, extending the device life for a further 5 years). It is recommended to test the functionality of the device using only the supplied Test Gas canister in order to avoid altering the trigger threshold of the sensor.