Honeywell Home THP9045A1098 C Wire Adapter Installation Guide
- June 6, 2024
- Honeywell Home
Table of Contents
Honeywell Home THP9045A1098 C Wire Adapter
Online Guides
honeywellhome.com
Overview
This product replaces the need for a C-wire (common wire) to power a
thermostat.
Only install if you do not have a C-wire available to connect to your
thermostat.
BEFORE
AFTER
Compatibility Check
Confirm you have a G and Y wire
Look at your wires. Do you have BOTH a G and Y wire labeled?
YES – This means your system is compatible. Proceed to Step 2.
NO – Your system is not compatible with the C-Wire Adapter. Call
1-855-733-5465 to find a pro-installer.
Relabel your G wire to be C
Use the provided labels.
Relabel your Y wire to be K
Use the provided labels.
Go to your furnace or heating system
This system is often located in your basement, attic, or garage. Bring labels,
flashlight, screwdriver and phone.
Remove cover of furnace or heating system
Open the furnace or heating system’s cover to find the control board.
Note: You may need to unscrew the cover (top or bottom).
Leave the power off.
Locate the bundle of wires that are the same as the ones at your
thermostat
Take a picture of the wiring
Take multiple pictures from different angles to capture all of the letters
next to the terminals.
G
C
R
W or W1 (not in all systems)
Y or Y1
Be sure to include the terminal labels and wires. You may need to reference
this image later.
Note: If you have wires connected to 2 R terminals, then you have a two-
transformer system. Call 1-855-733-5465
to find a pro installer.
Label the wires
Use the provided stickers to label the wires connected to the following
terminals:
G
R
W or W1 (not in all systems)
Y or Y1
Note: If multiple wires are connected to a terminal, only label the wires
running to your thermostat.
Disconnect the labeled wires
Be sure you have taken a photo of your wires before disconnecting.
Disconnect only the wires that you just labeled. Do not disconnect any
unlabeled wires.
If unlabeled wires disconnect, replace immediately.
Note: You may need a screwdriver to release wires from terminals.
Connect wires to the C-Wire Adapter
Firmly depress the terminal tabs and insert the labeled wires into the
“Thermostat” side of your C-Wire Adapter.
Insert the wires into their corresponding terminals as shown below.
Ensure the wires are connected
Gently tug on the wires to be sure they are connected to the C-Wire
Adapter.
Connect wires to control board
Take the wires from the “Equipment” side of your C-Wire Adapter and connect
them to the control board.
Be sure to remove the plastic tips and insert the wires into their
corresponding terminals as shown below.
Mount C-Wire Adapter
Use the included mount and adhesive pad to mount the C-Wire Adapter inside
your furnace or heating system.
Note: Make sure your wires are not over extended or strained.
a) Clean the surface
b) Firmly press the adhesive
c) Mount the C-Wire Adapter
Mount anywhere inside the furnace.
Close the cover to the furnace or heating system
Be sure the cover is completely closed. Some systems will not power up if the
cover is not fully closed.
Leave the power off.
You’ve connected the C-Wire Adapter. Go back to the “Installing Your New Thermostat” section of the Installation Guide to complete the installation.
Electrical Specifications
INPUT: 24V~@60Hz, 0.2A
Resideo Technologies Inc.
1985 Douglas Drive North,
Golden Valley, MN 55422
1-800-468-1502
33-00422ES—03 M.S. Rev. 04-20 |
Printed in United States
© 2020 Resideo Technologies, Inc. All rights reserved.
The Honeywell Home trademark is used under license from Honeywell
International, Inc. This product is manufactured by Resideo Technologies, Inc.
and its affiliates.
