6 Significant Furnace Controls

Gas furnaces are the preferred style of furnace set up in residential properties. They are equipped with numerous controls to make sure Safe and sound and economical operation. It is crucial to examine the furnace specifications and manuals to properly understand how the controls work. Listed below are 5 major furnace controls identified over a residential gas furnace.

Fuel Strain Regulator

As the fuel from the main line is subject matter to distinct pressures, a fuel strain regulator makes certain a steady fuel force into the burner manifold. This is generally FoundĀ type j thermocouple between the supply tank and the key gasoline valve. This guarantees your furnace receives the right volume of gasoline to burn; not far too weak and never too much.

Principal Gasoline Valve

Just like a gasoline pressure regulator is needed so is a principal fuel valve. Its main purpose is to regulate the movement of fuel from the surface offer line or storage tank for the gasoline burner. They come in a variety of sizes and shapes and usually located behind the front panel of the furnace. The valves will include things like a safety shutoff valve that means that you can switch off the leading fuel line plus the pilot gasoline. In a contemporary furnace that does not Possess a standing-pilot light-weight, these most important gasoline valves are identified as Digital ignition gas valves.

Mercury Flame Sensor

You will discover a mercury flame sensor in a more moderen furnace by having an Digital ignition process. It can be made up of the mercury-filled perception close, a capillary tube and an SPDT switch assembly. The sensor conclude is full of mercury and heats up with the immediate burner flame. When heated, the mercury liquid triggers the change and opens the gasoline valve.


A area thermostat is the key Charge of every time a furnace operates based on the temperature from the room. A thermostat senses improvements in air temperature that is certainly becoming heated and send out an electrical signal to open or close the automated gas valve of your respective furnace. Most thermostats are wired Using the pilot basic safety valve, limit Command and the automatic primary gas valve.


A thermocouple is the protection unit accustomed to detect whether the pilot mild is is lit ahead of the key gas valve is opened to produce fuel to the burners. A Thermocouple utilizes a warmth-sensing machine that senses the warmth with the pilot mild then converts it right into a electric powered existing making it possible for gas into your furnace to ignite.


At times known as a thermopile generator or millivolt generator, a thermopile is yet another protection product for the key gasoline line and pilot light. Much like a thermocouple, the heat-sensing product is accustomed to detect the pilot light is on. A thermopile is greater and provides a lot more energy than a thermocouple. The benefit of a thermopile is it does not require a transformer.