Kidde HD135F Fyrnetics Hardwire Heat Detector with Battery Backup

Met all of our needs.

Works great in an area where we cook all the time and the other “smoke detector “ was constantly going off. Easy to install

These are as easy to replace as just changing the battery. You unscrew the detector, pull out the power wires, then use a new detector with new battery (instead of the old one with new battery) before putting it back. Easy enough once you can reach the ceiling to do it.The company is very soft on when to replace. The support staff mentioned that a double beep indicates failure while a single beep is just asking for a new battery. So far so good. The unit hadn't actually failed. However, that same advisor suggested they should be replaced anyway as they were 15 years old. The warranty is 5 years, so she advised replacing them. I opted to replace since we have 16 foot ceilings and I would need professional help to reach them--costing more than the new detectors. However, these units appear to use a metalic "fuse" that melts at the appropriate temperature indicating a fire and triggering the alarm. Not obvious how this can go bad--ever.

Installed easily. Wired it to other Kidde smoke alarm in house (using some 14/3 cable). Tested and it communicated both ways, and never smoked itself ;)

Good price and quality, simple installation, fit into existing location