The Honeywell RTH7400D Programmable Thermostat offers electronic control for 24 Vac heating and cooling systems, as well as 750 mV heating systems. This guide details the installation and operation of the device.
For assistance with your Honeywell product, visit www.honeywell.com/yourhome or contact Honeywell Customer Care toll-free at 1-800-468-1502.
Important: Please read and save these instructions before proceeding with installation.
Installation Overview
The installation process involves several key steps:
- Preparing for installation, including checking included items and gathering necessary tools.
- Following important instructions, particularly regarding wire connections to avoid system damage.
- Removing the old thermostat carefully.
- Following special instructions for wiring, especially concerning 'C' wires.
- Labeling old thermostat wires accurately.
- Mounting the new wallplate to the wall.
- Connecting wires to the new wallplate.
- Installing batteries.
- Attaching the new thermostat to the wallplate.
- Configuring installer setup options.
Key Considerations
- Wire Connections: Never connect wires based on color alone; use the provided wire labels for accurate identification.
- Mercury Notice: If replacing a thermostat containing mercury, follow local waste management guidelines for proper disposal.
- Customer Assistance: Contact Honeywell Customer Care for any missing items or installation queries.
