Individuals get hung up over complicated terminologies like ‘hysteresis’ and more often than not, these terms can be simplified with an easy explanation that can be understood by anyone. In the same manner, hysteresis is considered an engineering terminology that is used to explain a simple ‘lag.’ It is specifically the way that a reaction lags a step or an action. Let’s take a closer look at this simple example below.
If you were to squeeze a piece of foam and then release it, you would hear a popping sound as if it popped back to its original form. However, it does not do so immediately. It goes back to its normal state in a slow motion. It lags this action until the release of your hands. Other forms of hysteresis are the same way.
The common use of hysteresis is during the use of magnetic and electronic systems. Thermostats are a perfect example. Without using technical applications and definitions of hysteresis, let’s look at how it applies to thermostats. The hysteresis thermostat also goes through a similar motion; it lags inputs from the surroundings for the main purpose of saving energy as well as preventing a furnace or air conditioner from enduring wear and tear as it frequently turns on and off.
If you live in a house that is poorly insulated and the temperature outside is a scorching 104 degrees, your main concern is how long it will take for the heat to penetrate your house while the air conditioning unit is running. Believe it or not, this would not take long. With a good HVAC system, your house will cool to about 72 degrees, which is quite comfortable. When the insulation is insufficient, in about one minute, the temperature will increase to 73 degrees and your air conditioner will kick in again. This cycle continues to be repeated frequently as your air conditioning unit is overworking due to the poor insulation. It is, therefore, difficult to maintain the comfortable temperature in the home.
You would not classify this thermostat as a hysteresis thermostat because of its lack of hysteresis in the programming. For that reason, it will constantly turn on and off. With a hysteresis thermostat, you can set your temperature to 72 degrees and be able to maintain it. Why? The temperature will go up to 74 degrees before cooling it to down to 71 degrees, allowing the HVAC system to relax. This saves on wear and tear and also fosters energy efficiency.
It is important to get your HVAC system working efficiently and therefore, you could consider using a hysteresis thermostat. It will definitely work in your best interest. Speak to a HVAC contractor to discuss your immediate needs.
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