Honeywell RTH6350D Review


Photo credit: Courtesy of

Ease of use is the hallmark of this 5-day/2-day programmable unit, which has a bright backlight and smooth installation that users appreciate. It will work with most systems, including multi-stage.

Pros: Consumer product experts give the Honeywell RTH6350D (starting at $43; available on Amazon) high marks for ease of use, and users mostly agree. In reviews on and Amazon, consumers report few problems with installation. Even those with little prior experience say clear instructions make the process very easy. They also say the thermostat is simple to program and control, with an easy-to-read LED backlit screen and large, intuitive buttons. Most users say the thermostat helps their homes maintain an even temperature, and some report tangible savings on their heating and cooling bills.

Cons: Many users wish they could set a larger temperature swing range than 1 degree, to keep their heating and cooling systems from kicking on too often while trying to maintain a precise temperature. Others say they dislike the "smart response" feature, which may turn on the heat or air too early in an effort to reach a set temperature by the exact time that's been programmed (however, this feature can be disabled). There are also a couple of reports on Amazon from users who complain of huge inaccuracies in temperature. But while it's typical to find some quibbling with every model's accuracy, large discrepancies, such as the 8-degree differences claimed here, suggest faulty units or faulty installation, as opposed to problems with this generally well-rated line. Finally, a handful of owners complain that there's a loud "click" when their heating and cooling systems turn on or off. For most, this is a minor annoyance, but it might be a bigger consideration in a bedroom.

Features: The Honeywell RTH6350D has 5-day/2-day programming functionality, which lets users set the thermostat to one schedule on weekdays and another on weekends. Each day is made up of four temperature periods. Users can also temporarily or permanently override the schedule. This universal thermostat is a good option for most heating and cooling systems: single- or multi-stage heating and cooling, including gas, oil, hot water, or electric; heat pumps with or without auxiliary heat; steam or gravity systems; and some gas fireplaces. It does not work with electric baseboards. It requires two AA batteries, and the interface can be removed from the wall for programming. The Honeywell RTH6350D is backed by a one-year warranty.

Takeaway: It's not a perfect thermostat, but the Honeywell RTH6350D should be satisfactory for users who want something that's low-fuss and versatile enough to work with most heating and cooling systems.