Honeywell Home C-Wire Adapter for Honeywell home Wi-Fi Thermostats and RedLINK 8000 series thermostats

This adapter works exactly as intended—I needed it to provide the C-wire for my Amazon thermostat installation. Ours has been in use since 2022! The instructions were good, and the product met all my needs perfectly! If you need a C-wire to install your smart thermostat, this is a solid choice.

This converter was easy to install and came with easy to follow instructions. No issues getting the Honeywell Wifi thermostat connected to our hvac system. Our home was built in the 70s and naturally lacked the 5th wire to connect a 24v line to the thermostat. I was skeptical when buying this as it seemed too good to be true to get that power wire this easily. No issues! Something I ran into during install that wasn't really covered in the wiring instructions: My furnace is an HE model, the yellow wire was split off the main circuit board on the furnace and it was ran to a float safety switch, then off to the thermostat from that switch. Make sure you wire in this box after the switch not directly off the circuit board. This float prevents the unit from running if it is full of water and not draining.

TL,DR: Using this with an Amazon Smart Thermostat and works fine. Though I did have a small moment of panic initially after installing everything and setting up the thermostat itself. As I was admiring my work and watching the thermostat come to life and wake up in its new home, it began “clicking on” and then immediately going blank for several seconds. At first I was thinking this may be part of the set up… until it didn’t click on again and was unresponsive in every way. At this point I just knew for sure I fried something, was going to have to call a technician out, and they were going to tell me I’d have to replace my entire system for thousands of dollars. I grabbed my multimeter and verified I had power coming to the furnace and then checked the small 3 amp fuse at the control board which was blown. I switched that out with one I luckily had on hand and everything came back to life as I threw the breaker back on. That was yesterday afternoon and everything has been working fine ever since. Further things I learned during this process: - What each wire does on a heat pump system (hence the pic with them identified). - This adapter combines the fan and condenser wires to free up a wire to be used as the C-wire - The C-wire is effectively the return for the 24v to the thermostat to complete the circuit (think chassis ground on a car or neutral on a home circuit). - If you have an unused wire on your thermostat cable, you don’t need this. Just hook that unused wire to the C-wire in your furnace (look for the blue wire coming from your outside unit and verify where it goes to the control board in the furnace) because even if you get this, you still gotta find a C wire to connect it to.

Great product; instructions were easy to follow and allowed me to install myself instead of calling an electrician (I’ve got no electrical experience). That said, I do wish there were different mounting options as my furnace had a sort of cloth like interior that made it impossible to mount using the adhesive.

Does exactly what is says.

This think worked great for about 5 months and then all of a sudden the thing kept buzzing and wouldn't turn my blower motor on, for the past 2 months I thought my furnace was malfunctioning until I finally put my hand on this adapter and the buzzing was coming from it. I removed it and had to re-install my old thermostat and the furnace works flawlessly. Don't waste you time or your money, I had seen a couple bad reviews but took a chance and now I've been ripped off for 40 dollars and months worth of headaches. Don't waste your money.

It's functional and easy to install if you're familiar with wiring schematics. Unfortunately, living in Florida, the humidity will eventually degrade the board inside the unit and it will fail if installed inside the garage(where my furnace is located.) Mine lasted several years before failing. If you're in a pinch and need to quickly wire a "C" or common wire, this will do the job. The better option will be to just go in the attic and run a wire for longevity. Troubleshooting may be problematic without prior electrical knowledge and HVAC techs are not cheap. I spent a few hours with minimal electrical knowledge troubleshooting before confirming the issue was the adapter. YouTube University for the win! 5 Stars for ease of installation 1 Star for durability

I didn’t have the ability to change to a five wire this adapter made my Honeywell thermostat work perfectly without any issues including Auto change over heat and cool, never ever causes an issue. Even as an Amazon renewed product. Nothing was wrong with it. I can only assume operator error from the last owner because the directions are so simple, just make sure to FOLLOW THE DIRECTIONS on the thermostat documentation because the wiring connection places are different than a normal hookup R G Y W instructions will tell you to use position K and other connections while using this adapter. So long as you follow the instructions, it works perfectly.