Where’s The Lennox Furnace Reset Button? [And How To Use It]

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Furnaces are sometimes confused for boilers, but these two are worlds apart. The central heating systems in many homes are either oil or gas furnaces. Over time, your furnace might have some issues. Manuals will suggest troubleshooting and resetting the furnace to solve some problems. If you own a Lennox furnace, you might be wondering where the reset button is. We asked the experts, and they gave us a direct answer.

The Lennox furnace has the reset button situated on the ignition control panel. The reset button has the label, Reset, boldly written on it. In the furnace's manual, the location of the reset button is indicated.

If you are looking for the reset button on your furnace, it means there's some trouble with it. Read on to find out what the reset button does and when to use it.

High energy efficient furnace in a basement, Where's The Lennox Furnace Reset Button? [And How To Use It]

The Reset Button's Location

Resetting a furnace is like rebooting a computer. The reset button in a Lennox furnace is not challenging to locate. Turn off the power supply before you start looking for the reset button in your furnace. This is a necessary safety precaution.

Once you have turned off the furnace, you can proceed to do these steps:

  1. Locate and expose the control panel of the furnace.
  2. Search for a raised button (mostly red).
  3. You'll find it on the ignition control panel.

Note: Most furnaces have a diagnostic light that flashes to indicate a problem. To decode the flashing of the diagnostic light, look for the instructions on the inside of the panels.

Why Do You Need To Reset A Lennox Furnace?

Over time your furnace might not be working as it once used to. But if you bought a house with a furnace in it, you might not be aware of what problems it has.

Luckily, manufacturers have added codes to help you detect problems with your furnace. Therefore, resetting a Lennox furnace is the same as troubleshooting.

Common Furnace Problems [And Their Causes]

Since a furnace is the primary source of heating in most homes, ensure that it is in good working order before the start of the cold season.

There are some common problems which occur from time to time in furnaces. You will save some money when you can identify the issues and their causes.

No indicator light

The fuse in the furnace powers the blower and control circuits that use electricity. The fuse will gauge the current consumed by the appliance to avoid overload or power shortage.

The indicator light won't blink if there's a burnt fuse. You'll need to change the fuse. Fuses used in furnaces are not more than 5 amps.

Check out these fuses on Amazon.

Flame Goes Off

Gas flame inside of the gas boiler furnace

Heating appliances for a living space shouldn't suddenly go off. Once you notice that when you turn on the furnace and the flame goes off after a few seconds, open the back panel and check.

Restart the furnace to find out if the furnace burners go off almost as soon as they go on. In this case, the problem could be that the flame sensor is dirty.

Note: Newer furnaces will go into lockout mode for three hours if the furnace tries and fails to ignite five times consecutively.

To remedy this issue, restart the furnace after a few seconds. If the problem persists, remove the flame sensor and clean the buildup.

Have a look at this flame sensor on Amazon.

No Heat

There could be several problems that will make a furnace not blow hot air into the vents. You will need to troubleshoot the furnace to find out where the problem lies. Your furnace might not be heating due to any of these conditions :

  • Clogged Air Filter: Remove and clean any dirty air filters. The leading cause of clogged air filters is soot, dirt, and debris.
  • Spoilt Thermostat: Check to see if the thermostat on the furnace is working correctly. Ensure that you check to see the temperature reading is correct too.
  • Leaky or Blocked Ducts: If one room is warm and the other is cold, it could be a leaky or blocked duct. Ensure that all registers are open. Look for any gaps in the system and seal them.
  • Dirty Chimneys: A blocked chimney can be one of the reasons why your furnace isn't working. Dead birds might fall inside and block the chimney.
  • No Fuel: Whether you have an oil or gas furnace, ensure the fuel tank has fuel. Always ensure that the furnace doesn't run out of fuel.

A person changing an air filter on a high efficiency furnace

Turned Off Switches

Sometimes the furnace might not be working because the switches are off. Check if the switches are turned on. The power and the thermostat switch should be on for the furnace to work.

Ensure that the gas valve has been turned on too. You might have forgotten to turn the gas valve back on.

Note: Proper maintenance and cleaning will have the furnace functioning well.

Here is a video that visually highlights different problems you might detect in your furnace:

How To Reset A Lennox Limit Switch

Reset the limit switch in a Lennox furnace with these three simple steps:

  1. Turn off the electric supply to the furnace.
  2. Then locate the control panel of your furnace. It could be on the top or bottom part of the furnace.
  3. Open the panel and search for a button near the ignition control box. Press and release the button to reset the furnace.

The limit switch is easy to locate on any Lennox furnace.

Do All Furnace Blower Controls Have A Reset Button?

Furnaces are required to have a reset button as a safety precaution. The reset button helps turn off the furnace in case of a problem.

If the furnace overheats or doesn't heat up, the reset button helps switch off the furnace immediately. Shut down the furnace to avoid triggering the electrical circuit and causing a fire.

You'll find the reset buttons in the blower compartment. They are often brightly colored.

Are Lennox Furnaces Oil Or Gas?

There are three types of modern furnaces: oil, natural gas, and electric furnaces.

Lennox furnaces, in particular, use oil and gas. These furnaces will deliver the comfort promised in both commercial and residential buildings.

Lennox oil furnaces are fuel-efficient. Although the initial installation cost might be high, they are durable and last long. When they have enough fuel, they heat the living space very fast.

Gas furnaces made by Lennox have been in the market for a long while. Their installation is affordable, and they work anywhere there's readily available natural gas.

Note: When installing a furnace, please consider which fuel is readily available in your vicinity. Most importantly, seek a professional's help.

How A Furnace Works

A home high energy efficient furnace in a basement

The basics of a furnace are straightforward. Knowing the basic furnace functions will help you avoid calling the maintenance guy unnecessarily. It will also help you save a lot of money on house calls.

The main components of a furnace include:

  • Control system
  • Gas valve [for gas furnaces]
  • Heat exchanger
  • Ventilation system
  • Blower
  • Burner
  • Oil tank [for oil furnaces]

For a furnace to heat the living space efficiently, it should work in the following manner:

  • The thermostat signals the furnace, and the gas valve opens and ignites the burner. The thermostat notifies the gas valve how much gas should be burned to get the temperature on the thermostat.
  • The blowers blow hot air into the duct and ventilation system. In turn, the heat gets to the living space via the vents.

Furnace Safety Tips

All appliances have safety measures that must be adhered to. Gas, oil, or electric furnaces have safety measures too.

  • In case you smell gas, do not operate the furnace. Immediately, call in a professional to solve the problem.
  • Always check the heat exchanger for any cracks or dents.
  • Inspect the vents and ducts often, and remove any debris and dust that might clog them.
  • Have a look at the color of the flame often. The color of the flame will let you know if you have a fuel or burner problem.
  • Call in a qualified technician for a monthly or bi-monthly check-up of your furnace.

Home repairman working on a furnace

In Closing

Heating your living space can be costly, thus, ensure that you are knowledgeable about the heating system in your home. For your Lennox furnace, you might as well remember that its reset button is located on the ignition control panel.

It is wise to have your furnace in proper working order throughout the year. Troubleshoot the appliance before the start of the cold season to avoid any problems.

Before you go, check out these posts on well pump and sump pump:

Does A Well Pump Need A Control Box? [By Type Of Pump]

Does A Finished Basement Need A Sump Pump?

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