
The C-Wire provides a continuous flow of power to operate more advanced 24-Volt thermostats and is most often needed when upgrading to Wi-Fi and wireless thermostats. The C-Wire Power Adapter converts existing thermostat wires to common wires (C-Wires) to help make Honeywell Home Smart Thermostats compatible with homes that may be missing this "common" wire. Features easy push terminals and an adhesive mount to attach the adapter to the outside of your furnace, while a closed cover conceals internal components — making installation quick and easy.
Q: Does this adapter have a cover?
A: Yes, it has a closed cover that conceals internal components.
Q: What does the C-Wire Power Adapter do?
A: It converts existing thermostat wires to common wires (C-Wires) to help make Honeywell Home Smart Thermostats compatible with homes that may be missing this "common" wire.
Q: What is the purpose of this device?
A: This device helps power connected thermostats that require a c-wire.
Q: How is the C-wire adapter installed?
A: It has easy push terminals and an adhesive mount to attach the adapter to the outside of your furnace.
A: The C-Wire provides a continuous flow of power to operate more advanced 24-Volt thermostats and is most often needed when upgrading to Wi-Fi and wireless thermostats.
Q: How to lock the wires into a c-wire adapter for a house thermostat.
A: Hi Crashq2u, thank you for reaching out. You have to press the tab of each wiring terminal to insert or remove the wires to or from the adapter. We will be happy to help you checking the wiring. Feel free to contact our tech support team at (800) 633-3991 or send us a Private Message at our Honeywell Home Facebook account. - Maria
Q: how to determine that my system has C wire or not
A: Hi Nunu, thanks for the question. You can determine if your current wiring has a C-wire by checking the thermostat and look for a wire connected to the C-terminal or have a unused wrapped in the bundle. If you don't, you can follow your thermostat wires to the system and see if you have a C terminal available, this is where the adapter is going to be installed.

The C-Wire provides a continuous flow of power to operate more advanced 24-Volt thermostats and is most often needed when upgrading to Wi-Fi and wireless thermostats. The C-Wire Power Adapter converts existing thermostat wires to common wires (C-Wires) to help make Honeywell Home Smart Thermostats compatible with homes that may be missing this "common" wire. Features easy push terminals and an adhesive mount to attach the adapter to the outside of your furnace, while a closed cover conceals internal components — making installation quick and easy.

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| Pros for Honeywell Home - C-Wire Power Adapter - White | |||
|---|---|---|---|
| There were no pros for this product— | There were no pros for this product— | Ease of Use, Overall Performance, Installation, Connectivity, Remote Control | Ease of Use, Overall Performance, Installation, App Usability, Design |
| Cons for Honeywell Home - C-Wire Power Adapter - White | |||
| There were no cons for this product— | There were no cons for this product— | Compatibility, Size, Temperature Accuracy, App Functionality | There were no cons for this product— |
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Works great, fairly easy to install and replaces the mess of wiring.
Easy gadget to make ac thermostat work c-wire power adapter
Assistant1 Posted
Work excellent. Instructions are clear and good use of this item.
JulianC Posted