4WT-B 4-wire, photoelectric i3 smoke detector with a 135 Degree fixed thermal sensor

Replaced an older 4 wire smoke detector that had yellowed over time. Works perfectly and has the added capability of fixed rate heat detection.

Perfect replacement for System Sensor model # 2112/24TS 4-wire PhotoElectronic smoke detector. Easily removed old unit and rewired the new unit by connecting red wire to + in terminal, single black wire to - in/out terminal, two black wires to no terminal and green and white wires to com terminal. Tested the newly installed unit by inserting allen wrench into recessed test switch and applied heat from a hair dryer. Both test sounded the alarm. Unit is correctly wired and installed when the green LED light is blinking.

Exact replacement for my unit. Left original base plate and added new sensor. Alarm system recognized and all is working.

Perfect replacement for 35+ year old alarm system smoke detectors. These do not have sirens in them. These are designed for 12 volt DC home alarm systems. I used these with a "Konnected" smart panel alarm system update. I have five of these installed. It is made for a four or five wire system. It is a "Normal OPEN" type of alarm. It closes when smoke or 135 degree heat is detected. You can test thermal sensor with a hair dryer.

This purchase was to replace an inoperative sensor. It works as design and was easy to install. I was disappointed the device didn't come with mounting screws, but luckily I retained the old one. I've had this device for over 2 months and there are no issues.

Bought this to replace the original 20-year old smoke detector. Perfect fit in the original wired mounting base. Sensor reset in alarm system cleared the trouble code.

I bought this detector after my 10 year old unit (same mfg and everything!) bit the dust and said there was fire every 3 hours. Not fun at 3, 6, 9 in the morning...you get the idea. So I did some quick research and found this unit to be priced well, and did the purpose of heat and smoke- just what I wanted. Because this was the same mfg, the installation was almost wire for wire- not much needed to change. The instructions were clear just in case you're not comfortable doing this. But I think I had the old one down and the new one up within 7 minutes. And works like a charm! Tested it out with a hair dryer and then with a candle that I blew out...quick response, very pleased! In a nutshell, if you want a smoke/heat detector that is easy to install and reliable. Go with this one!

Great product!