The GEMC-WL-HEAT is a high-quality wireless 135°F (57°C) fixed-temperature heat detector with Rate of Rise. It is compatible with Napco's GEM-RECV supervised receivers that monitor alarms, restores, low battery, tamper and status. The GEM-WL-HEAT incorporates circuitry that will transmit an alarm signal upon an alarm condition, generate an hourly supervision test signal to the receiver and also monitor and annunciate low battery. Coding switches are not required or used in the GEMC-WL-HEAT. Each transmitter is assigned a unique identification code number at the factory. The transmitters are powered by one 3V Lithium battery (supplied) that can power the unit for up to two years. If the battery voltage drops below normal, a low-battery report will be sent to the receiver with any status or alarm transmission.