Product Description The Kidde Heat Detector, Hardwired with Battery Backup & 2 LEDs, Interconnectable, model HD135F, is an AC/DC powered heat alarm that operates on your home's 120V power source. In the event of a power failure, the Kidde heat alarm comes equipped with a 9-Volt battery backup (included). Using heat sensing technology, the wired heat alarm detects temperatures rising above 135⁰ Fahrenheit, alerting homeowners to dangerous temperatures unlike a smoke alarm, which only detects smoke. Heat detectors are recommended for areas where a smoke alarm may not be appropriate, such as in a kitchen, garage, attic, or other area where smoke or dust may set off a false alarm on a smoke detector. Installing both smoke and heat detectors in a home can provide extra protection while triggering fewer nuisance alerts. The heat alarm includes a quick-connect power harness to make installation fast and easy. An 85-decibel alarm sounds when the high temp sensor detects elevated heat conditions. Two LEDs indicate the heat sensor alarm's status: a green LED is constantly 'on' when AC power is present, and a red LED will flash every 30-40 seconds to indicate that the heat alarm is operating properly; the red LED and will flash rapidly when the unit is sounding until air temperature is reduced. The Kidde heat detector can be used as a single unit or interconnected with up to 24 Kidde devices (18 of which can be initiating) in a multiple-station arrangement, not exceeding the NFPA (National Fire Protection Association) limit of 18 initiating devices (smoke, heat, CO). It is possible to interconnect 6 strobe lights and or relay modules. Ideal for garages. UL Certified with a 5-year limited warranty. Amazon.com Kidde Heat Alarm view larger Kidde HD135F 120VAC Wire In Heat Alarm with 9V Battery Back Up Rather than smoke, the Kidde HD135F responds to temperatures rising above 135˚F. This unit is interconnectable with other units of the same like. The interconnect system must not exceed the NFPA (National Fire Protection Association) limit of 18 initiating devices (smoke, heat, CO, etc) interconnected. It is still possible to interconnect 6 strobe lights and or relay modules in addition to the 18 initiating devices. This unit is UL Listed. Consumer benefits The Kidde HD135F provides you and your family an early warning to dangerous temperatures greater than 135˚F. This unit also includes a tamper resist pin to deter tampering or theft. What's in the box One single Kidde 135F smoke alarm. A five-year limited warranty.SpecificationsInterconnectable – Interconnects with up to 24 Kidde devices of which 18 can be initiating Test Button – Tests unit’s electronic circuitry, horn and battery function 9V Battery Back Up – Provides continuous protection even during power outages Red LED – Flashes every 30-40 seconds to indicate proper operation Low Battery Indicator – Alerts user in the event of a low or missing battery Quick Connect Power Harness – Makes installation fast and easy From the Manufacturer The Kidde 120-Volt AC Hardwire Heat Alarm gives you and your family an early warning to dangerous temperatures of 135-Degree F or more. This unit can be used as a single station unit or it can be interconnected to up to 24 Kidde devices in a multiple station arrangement. The interconnect system should not exceed the NFPA interconnect limit of 12 smoke alarms and or 18 initiation alarms. The heat detector includes a tamper resist pin to help deter tampering or theft. See more