Honeywell RTHL3550D Quick Installation Guide

Installation Honeywell RTHL3550D is Easy

  • Label wires and remove your old thermostat
  • Install and wire your new thermostat
  • Set your new thermostat to match your heating/cooling system

– It is preset for the most common system

If your system type is:

  • Multistage Heat and Cool
  • Heat Pump* without Backup Heat
  • Heat Pump* with Backup Heat
  • Heat Only
  • Cool Only

Continue with advanced installation
on page 11 to match your thermostat to your system type. *Heat Pump—an air conditioner that provides cooling in the summer, and also runs in reverse in the winter to provide heating. If you are not sure of your system type or if you have other questions, call us toll-free at 1-800-468-1502.
This thermostat works on 24 volt or 750 mV systems. It will NOT work on 120/240 Volt systems.

Advanced Installation
System setup........................................................................12
Wiring...................................................................................22
Troubleshooting....................................................................25
Customer assistance............................................................27
Limited warranty...................................................................28

Read More Honeywell RTHL3550D Quick Installation Guide on PDF Below

Honeywell RTHL3550D Quick Installation Guide