Thermostats have become an essential component of many homes, particularly during the winter. That’s because they help control the reactions of the HVAC systems to external temperature. Most people, however, are unaware of the underlying principles that govern how a thermostat operates.
It takes advantage of the external temperature to ensure the internal temperature is constant. But while it expands when it gets too hot, what does a thermostat do if it gets too cold?
It contracts to turn on the heat. That’s the basic principle behind the working of the thermostat. Let’s have a more in-depth look at how a thermostat works in an HVAC system.
How Does a Thermostat Work?
Thermostats use the principle of thermal expansion to switch on and off an HVAC system, which means that any changes in the external temperature will either have them expand or contract.
Now, when the conditions get hot, the thermostat expands and switches off the HVAC system to ensure a colder breeze. That enables the thermostat to cool the house or car.
When the external temperatures get too cold, on the other hand, the thermostat contracts and cause the HVAC system to turn on the heat. That raises the external temperature of the house or car, making it warmer.
That’s what makes the thermostat one of the most integral parts of an HVAC system. It also enables them to work in different applications such as car engines and home heating systems.
Most traditional thermostats had the bimetallic strip that caused the shifts whenever there was a temperature change. The bimetallic strip was typically two metals that had opposite roles in the thermostat.
When the temperature increases and becomes too hot, one metal in the bimetallic strip expands, causing the thermostat to bend. The bending breaks the circuit and switches off the heater.
The bimetallic strip regains its original shape with a cooling of the temperatures, which then restores the connection to the circuit. The heater cranks up the heat to get rid of the cold.
The two metals work in concert to cause a mechanical displacement whenever there is a temperature change. The more modern thermostats don’t, however, use the bimetallic strips.
It is a more sophisticated gas system that you are likely to find in modern HVAC systems. That doesn’t mean the old bimetallic strip method isn’t still in use. Some thermostats still have bimetallic strips.
You can see that the thermostat works just like the human body. Whenever you get too cold, you shiver to enable your body to raise the temperature. The reverse happens when it becomes too hot. You sweat to allow your body to cool itself.
What are the Different Types of Thermostats?
Having seen the way a thermostat works and the science behind it, are there different types of thermostats? Yes, there are. The two main types are mechanical and digital thermostats.
Digital thermostats are a more modern invention compared to mechanical ones. Besides the two, electronic thermostats are also quite common. All this has enabled the thermostat to be efficient and more responsive.
Mechanical thermostats are the ones that still work with the bimetallic strips. That, however, isn’t that efficient when you compare it to the digital or electronic thermostat. The bimetal doesn’t react to changes in temperature as fast as digital thermostats.
Mechanical thermostats might be as far out as 5 degrees for the temperature. They, however, are beloved by most people because they are pretty cheap compared to their digital counterparts.
What are the Signs of a Faulty Thermostat?
Thermostats, too, are prone to the occasional issue. That might be because they are old, or it might point to a slight malfunction. Whenever a thermostat gets to this point, there will be clear signs that can help you recognize a problem.
- Faulty Thermostat Readings
This is one of the first signs that you need to check the thermostat. False readings will reverberate across the HVAC system and cause your air conditioner to get the temperatures wrong.
That means there will be an issue whenever you want to increase the temperature.
- Nonresponsive Display
How else are you to operate the thermostat without the display? If you notice that the display isn’t showing anything, then it’s a clear sign you need to check the thermostat.
- No Responsiveness to the On and Off Switches
The thermostat should be able to work immediately after you turn your air conditioner on. If it doesn’t, then it means it has a problem. The issue might be minor or a major issue that will need you to call a professional to help.
- Short Cycling of your HVAC System
Short cycling by your AC might be from other sources, but it can also be thermostat issues.
- Alarmingly High Energy Bills
A faulty thermostat will get you in trouble by having the air conditioner working poorly. That might translate to uncharacteristically high energy bills.
Common Thermostat Troubleshooting Techniques
It is not all the time when a thermostat malfunctions that you call an expert. Sometimes it is usually a minor issue that you can easily troubleshoot with the below tips.
- Check the batteries: sometimes it is the batteries that are no longer working. Always check them first before making any conclusions.
- Circuit Breaker-always check the circuit breaker before deciding anything else. Maybe the circuit breaker has broken the power connection, causing the thermostat to appear faulty.
- Check the fuse: this might also be a possible issue.
If it isn’t any of the above issues, then you can call an expert to come and check it out.
What Does a Thermostat Do If It Gets Too Cold? We hope we have given you the answer you needed. We also hope you know the principle behind their functioning and a few tricks you can use to troubleshoot them.
Thermostats have become a significant part of most households, so you need to know how to use them.
- Can You Run A Car Without A Thermostat? The Best Answers
- White Rodgers Thermostat Blinking Snowflake – How to Fix It?
- Thermostat Reads Higher Than Actual Temperature – Causes & Solution
- How To Turn Off Auxiliary Heat On Honeywell Thermostat: Best Solution Ever
- The Room Temperature Doesn’t Match the Thermostat Setting – What to Do
Let Us Know How We’re Doing!
Did this expertly prepared resource answer your question?
Do you have another question about home maintenance, home improvement projects, home appliance repair, or something else?