Understanding how furnaces work
How do furnaces work? Most homeowners would simply answer this question by saying furnaces work by keeping them warm. True enough; a furnace’s main function is to keep you warm during the brutal Canadian winters. However, there is more to the actual process of keeping you warm than just magically converting chilly air to something warm and comforting. Because furnace repairs are inevitable, it becomes important for every homeowner to understand how furnaces work. By having a general idea of how the process goes, it gives every homeowner a step ahead in case something in the system isn’t working right.
What Thermostats Do
A thermostat is what signals your furnace to kick in and do its heating job. The thermostat works by recognizing if the temperature in the home has dipped to a certain degree and provides the go signal for the furnace to start the heating process. The most popular type of thermostats today is the programmable kind. This small device can be set up to automatically heat up the home when people are in the house and turn the temperature down when nobody is around. The common problem that most homeowners encounter with thermostats includes a faulty thermostat that doesn’t send any signal for the heater to work or when the thermostat isn’t reading the temperature correctly which keeps the furnace running all the time and drive up your utility bills.
The Process of Sucking In Air
When the thermostat sends in the signal for the furnace to start the heating process, the furnace actually requires air to get the process started. The furnace fan sucks in the air from the room or outside to create combustion airflow. When the airflow is sufficient, the air gets heated. There is a standing debate as to the better source of air. Some say that sucking the air from outside brings in a healthier and more pure air as compared to the air from a damp utility room or an unfinished basement. Others say that the winter air temperature can be too much for a furnace and so it creates a heavier workload for your heating system. Either way, the air drawn in still goes through a number of processes that create a final product of air that is pure and warm.
Gas Valve Opens / Ignitor Engages
One of the most common areas prone to furnace repair happens within the gas valves and the ignitor. When the fan is able to draw in a sufficient amount of airflow for combustion, the gas valve opens releasing gas to the burners where the ignitor generates a steady blaze. Old furnaces work just like how gas stoves do making use of a pilot light instead of an ingnitor to ignite the gas when it’s turned on. The problem with the pilot light is that it often goes out and would again require to be lit back up. On the other hand, the modern furnace units usually feature an ignitor that automatically turns off as soon as it detects flame.
Air is Blown Over Heat Exchanger
When the furnace burners are set ablaze, the air is pushed over to the heat exchanger by the blower motor. The heat exchanger does the function of taking out the cold from the air and making sure that the air is warm enough before it gets pushed through the ducts and the vents. The furnace will continue generating warm air until either the preset time is completed or the thermostat recognizes the temperature suitable for your heating needs. You can force the heating process by cranking the temperature up; however, this can put some pressure on your furnace and eventually cause it to prematurely malfunction.
Gas Valve Turns Off and Blower Motor Cools Off Heat Exchanger
When the room temperature reached the level that the thermostat has set, the thermostat signals for the process to shutdown. This process involves turning off the gas valves while the blower motor works to cool off the heat exchanger until it completely shuts down while it waits for another signal from the thermostat to start another heating process. Heat exchangers play quite a huge role in getting the heating process completed so they are always in constant pressure especially during the viciously cold winters. It is also for this reason that heat exchangers are likely to go through a number of repairs throughout your furnace’s lifespan.
They say, ‘knowing is half the battle’. The other half may not necessarily mean you are now qualified to do some serious furnace repairs after understanding how furnaces work. The fact that you are now aware of the tedious process that your furnace goes through every time you require heat for your home makes it easier for you to make a somewhat accurate diagnosis of your heating system’s current situation and make a reasonable decision in terms of the resolution that your unit necessitates.