You recently replaced a defective furnace, and you’re wondering if your old thermostat can be used with your current two-stage furnace. There are several reasons why you might need to replace an outdated furnace before you can move into a new home. But Do I Need A Special Thermostat For A Two-Stage Furnace?
It’s a no, but there are a couple of caveats to that. Although a standard thermostat can be used with a two-stage furnace, additional considerations are to keep in mind. If you have a two-stage furnace, you may want to read on to learn more about the pros and cons of keeping your current thermostat or upgrading it.
What Does a Two(2)-Stage Furnace Mean?
A 2-stage furnace, also known as a dual-stage furnace, is a type of heating system that has two levels of heat output. Unlike a single-stage furnace, which only operates at full capacity, a two-stage furnace can adjust its output based on the heating demand.
Here’s a brief explanation of how it works:
- First Stage: This is the lower stage, where the furnace operates at around 70-80% of its full capacity. This stage is sufficient for most of the heating season and helps maintain a consistent temperature while using less energy.
- Second Stage: This is the higher stage, where the furnace operates at 100% capacity. This stage is activated when the first stage is not sufficient to meet the heating demand, such as during extremely cold weather.
The main advantage of a two-stage furnace is its ability to provide more even heat distribution and energy efficiency. Since it operates at a lower stage most of the time, it runs for longer periods, resulting in fewer on-and-off cycles and less energy consumption.
| Stage | Output | Usage |
|---|---|---|
| First Stage | 70-80% of full capacity | Most of the heating season |
| Second Stage | 100% of full capacity | Extremely cold weather |
How Does A 2-Stage Thermostat Work?
A 2-stage thermostat, at its most basic, can turn on the furnace’s stage two burners based on certain parameters. After reaching the desired temperature, the stage two burners are turned off, and the stage one burners (low heat mode) are used exclusively to maintain them.
Modern two-stage furnaces automatically engage their stage two burners if the goal heat is not obtained after a pre-determined amount of time (the exact number of minutes can vary per model and manufacturer). This can lead to wasted gasoline if you don’t have a two-stage thermostat.
Stage two burners automatically activated by furnaces can waste fuel since they can be activated even if they are not needed. In the same way as when it’s just a few degrees off. This can happen if you have a single-stage thermostat and a 2-stage furnace.
Temperature variations can be calculated and compared to the furnace’s rate to heat the house using an advanced two-stage thermostat. It uses fewer stage two burners and more stage one burners to stabilize temperatures.
These two-stage thermostats monitor the time it takes to get to the desired temperature. To ensure that you wake up in a warm house, the thermostat can be programmed to start at a specific time the following day. It’s capable of calculating the best time to turn on the heat without resorting to stage 2 burners.
What Is The Distinction Between A Single-Stage And A Dual-Stage Thermostat?
A two-stage thermostat is explained above. On the other hand, a single-stage thermostat can switch the furnace on and off depending on how much heat is needed. The key distinction is that a single-stage thermostat cannot manage whether a two-stage furnace is set to high or low heating. The fuel savings that a two-stage furnace can provide may be reduced.
Is It Possible To Use A Single-State Thermostat With A Two-Stage Furnace?
The answer is yes, but there is a condition. Control boards for two-stage furnaces are usually adjustable to work with a single-stage thermostat or a two-stage thermostat. A single-stage thermostat for a two-stage furnace will ignite the stage two burners after a certain amount of time, and the thermostat’s signals will not be used to control the furnace’s operation.
Stage two burners can waste fuel if they’re left on when they’re not needed. Inconsistent and uneven heating can also be a problem. In addition, many thermostats can alter furnace start times and avoid utilizing stage two burners entirely. Stage one burners can be used earlier and longer to achieve and maintain the desired temperature.
The number of times the furnace has to shut down and restart during the day can be reduced by using stage one burners to maintain the temperature. As a result, the furnace’s components last longer. To replace a single-stage thermostat with a two-stage thermostat, you’ll need to run additional wiring through the wall. If you don’t feel it easy doing this yourself, hire a professional to perform it for you.
Conclusion
So, Do I Need A Special Thermostat For A Two-Stage Furnace? The furnace will not be harmed by using a two-stage thermostat. A single-stage thermostat is compatible with the control board, so the furnace may still run both stages. After around 10 minutes, the control board would activate the second stage.
It is possible to utilize a single-stage thermostat with a two-stage furnace, but the efficiency and fuel economy that a two-stage furnace can provide will be reduced. The greatest way to save energy is to pair a 2-stage thermostat with a 2-stage furnace. Your furnace’s parts can also benefit by lowering the number of times it shuts down and restarts during the day.
