Lennox Furnace Reset Button

Posted by: Mas Broto
Lennox Furnace Reset Button

If you’re the proud owner of a Lennox furnace, you’ve made a choice that countless others trust for their heating needs. But even the most reliable of furnaces can encounter a hiccup now and then. Overheating, for instance, is a common concern that can send homeowners into a spiral of worry. Here’s where a critical component, the Lennox furnace reset button, plays a vital role.

Picture this: your Lennox furnace starts to overheat or hits a snag in its operation. Rather than pushing on and risking damage, a built-in component, also known as the ‘Limit Control’ switch, promptly restores things. This automatic halt isn’t the end of the story, though. Quite the opposite – it’s an intentional pause for safety and a signal for you to step in.

Resetting a Lennox furnace isn’t a daunting task—it’s a simple, straightforward process that can have your home’s heating system restored in seconds. Let’s walk through the purpose of the furnace reset button, find out where it hides, and learn how to coax your furnace back to life.

Locating the Lennox Furnace Reset Button

The reset button is usually red or yellow and located on the front or side of the ignition control box in your Lennox furnace.

lennox furnace limit switch location

The location might vary slightly depending on your model, so when in doubt, check that manual (or find it online with your model number).

Step-by-Step Guide to Reset Your Lennox Furnace

Resetting your Lennox furnace when it’s gone off on a limit or high-temperature condition is a procedure you can often do yourself. Still, it’s important to proceed with caution and follow these steps meticulously to ensure your safety and the proper functioning of your heating system.

Step 1: Power Down

Before laying a finger on your furnace, it’s crucial to eliminate any electrical hazards. Make your way to your electrical service panel, which might be located in a basement, garage, or utility closet. Here, you will find a series of circuit breaker switches. Look for the one marked as “Furnace” or “Heating System.” Flip this switch into the “Off” position. This action will cut off the power to your furnace, ensuring you can safely proceed with the reset process.

Step 2: Access the Control Panel

Your next task is to locate and remove the control access panel on your Lennox furnace. The position of this panel varies with the furnace model: it’s typically the bottom panel on downflow models and the top panel on upflow models. Once you’ve identified the correct panel, you’ll want to carefully lift it and pull it away from the furnace’s body. This should be done gently to avoid disturbing any internal components. With the panel safely removed, set it aside so it won’t be in the way.

Step 3: Locate the Reset Button

With the inner workings of your furnace now exposed, it’s time to find the ‘Limit Control’ switch. The switch is usually conspicuous and is located to the right of the furnace’s ignition control box. It’s often marked and raised, making it accessible. This small but mighty button is the key to resetting your furnace.

Step 4: Reset the Furnace

Now, you’re ready to reset the furnace. Press the ‘Limit Control’ switch gently. You should feel a click as the button engages. It’s a simple push-and-release action. This should reset the limit switch and is the first step toward getting your furnace up and running again.

Step 5: Reassemble and Power On

It’s now time to put things back together. Carefully replace the furnace control access panel by reversing the removal process. Once the panel is securely back in place, return to your electrical service panel. Now, with a flick of the wrist, flip the circuit breaker switch for your furnace back to the “On” position. This will restore power to the unit.

After completing these steps, your Lennox furnace should be ready to operate normally again. Keep an ear out for the startup sequence, and observe the furnace as it begins to run. It should start without issue, but if it doesn’t, or if it goes off on the limit again, this could indicate a more serious problem requiring professional attention.

Remember, while a reset can be a quick fix, it’s not a cure-all for underlying issues that might be causing your furnace to overheat. Regular maintenance is key to a healthy, long-lasting heating system.

Troubleshooting Tips After Resetting

Say you’ve hit that reset button, but your furnace is stubborn. Don’t sweat it. Check a few things before you wave the white flag:

  • Is the filter cleaner than a whistle? A dirty filter can cause all sorts of drama.
  • Is the thermostat set to “heat” and turned up high enough to call for heat?
  • Are all switches and breakers related to the furnace in the “on” position?

If all these check out and your furnace is still on strike, it’s time to phone a friend — a certified Lennox technician, that is.

When to Reset Your Lennox Furnace

Below are some of the most common scenarios where a reset could be the first step in getting your heating system back on track.

  1. Empty Fuel Supply: If your furnace runs on gas or oil and there’s no heat, the first thing you should check is whether there’s fuel available. An empty tank won’t fire up, which could be the whole issue.
  2. Valve Obstructions: Valves control the flow of fuel to your furnace. If these are accidentally turned off or become obstructed, your furnace won’t receive the fuel it needs. Ensure that all valves are open and clear of debris.
  3. Air Filter Complications: A dirty air filter can cause your furnace to work harder than it needs to, leading to overheating and shutdowns. Conversely, if you’ve just changed your filter, your furnace may need a reset to adjust to the change in airflow.
  4. Flame Sensor Issues: Your furnace’s flame sensor plays a crucial role in safety. If it becomes dirty, it may not function properly and could cause the furnace to shut down. Cleaning and then resetting your furnace can often solve this problem.
  5. Overheating: Just like humans, furnaces can overheat. If your furnace runs excessively or has restricted airflow, it might need a break. A reset can help it cool down and start fresh.

If you’ve encountered any of these issues and resolved the underlying cause—refilled your fuel, cleared the valves, replaced or cleaned the air filter, or cleaned the flame sensor—a reset is the next logical step.

A reset after addressing a specific Lennox furnace problems helps the system recalibrate and ensures that everything is running smoothly. However, if you reset your furnace and the same issue persists, or it shuts off again soon after, it may be time to call a professional. Regularly scheduled maintenance is the best way to prevent these issues, but knowing how to perform a reset when needed is a valuable skill for any homeowner.

Maintenance Tips to Avoid Frequent Resets

Prevention is better than cure, am I right? Keep your Lennox furnace from throwing too many errors by:

  • Changing or cleaning furnace filters regularly.
  • Scheduling annual maintenance check-ups.
  • Keeping vents and registers unblocked and clean.

A little TLC goes a long way to keep your furnace running without a hitch.

Well, there you have it. The reset button on your Lennox furnace isn’t just a button; it’s a first line of defense and often an easy fix to common furnace hiccups. Remember, though, it’s not a miracle worker. Regular maintenance and knowing when to call in the experts are key to keeping your home cozy and your furnace happy.

mas broto avatar

Mas Broto

Have been in the heating and air conditioning (HVAC) industry for over 20 years. He is person that will grow and thrive to learn more about the HVAC industry throughout his career. Mas Broto is also a blogger, who's dedicated to bringing you the best knowledge to get ahead in the game of life.

Related Posts