Shop Honeywell Home Wireless Combo Smoke and Heat Detectors at GeoArm Security. Browse 5800-Series (345 MHz) and PROSiX encrypted sensors designed to detect smoke, rapidly rising temperatures, and dangerously high heat in residential and commercial properties. These life-safety devices alert the connected alarm system when signs of a potential fire are detected. Honeywell-Compatible security systems support GeoArm 24/7 professional UL-listed central station monitoring or DIY self-monitoring with no long-term contract.