If Your Rheem Furnace Isn’t Working, This Might Be the Fastest Fix
Problem
Your Rheem furnace suddenly stops working, and your house starts getting cold fast. You might see blinking lights or error codes on the control board, or your system is just blowing cold air. If this sounds familiar, you’re not alone. One of the most common questions we get is:
“How do I reset my Rheem furnace?”
Expertise
As a 20-year HVAC and plumbing veteran, I’ve worked on hundreds of Rheem units across the Steubenville, OH area. Whether it was a Rheem Classic 90 Plus in Wintersville or a Prestige Series modulating furnace out in Richmond, I’ve seen firsthand that many issues can be fixed with a simple reset—if you know how to do it correctly.
Promise
This guide will show you exactly how to reset your Rheem furnace, step-by-step, the right way. We’ll also explain when resetting isn’t the solution and what to do next if the issue keeps coming back.
Step-by-Step: How to Reset Your Rheem Furnace
When Resetting Doesn’t Fix It
Sometimes a reset won’t solve the underlying issue. If your Rheem furnace still won’t start or keeps shutting off, it might be due to:
- Dirty flame sensor
- Faulty pressure switch
- Blocked intake or exhaust vent
- Limit switch trip from overheating
- Ignitor failure
Real Example from Alex: A homeowner in Mingo Junction called about a Rheem that was blowing cold air. I walked him through a reset, but it didn’t help. After a quick visit, I found a dirty flame sensor. A simple cleaning got it firing like new.
If the reset doesn’t work, call a professional HVAC technician who knows Rheem systems.
Frequently Asked Questions
Where is the reset button on a Rheem furnace?
On many Rheem models, the reset button is located near the blower motor or burner compartment. It’s usually red or yellow and may be recessed.
What does the blinking light on my Rheem furnace mean?
A slow blink every few seconds usually means normal operation. Rapid or repeated blinks indicate a fault. Count the blinks and refer to your owner’s manual.
What should I do if my Rheem furnace keeps turning off after a reset?
If the unit short cycles or shuts off again, there may be a deeper issue like a clogged filter, bad flame sensor, or pressure switch problem. Schedule a repair visit.
Why won’t my Rheem gas furnace start even after resetting?
If your gas furnace doesn’t ignite, the issue might be with the ignitor, gas valve, or airflow restrictions. Resetting won’t fix a mechanical failure.
Still Need Help? Honest Fix Offers Free Exact Quotes
At Honest Fix, we’re trained on every Rheem model, old and new. As well as all other brands of furnace problems. If a reset doesn’t solve your problem, we’ll diagnose it fast and give you options on repair or replacement.
Alex Largent
Alex Largent is the Owner and Senior HVAC Efficiency Analyst at Honest Fix Heating, Cooling & Plumbing. With more than 20 years of field experience, NATE and EPA certifications, and a hands-on leadership style, Alex teaches his team to fix systems right the first time — with transparency, precision, and no upsells. He writes about HVAC diagnostics, home energy efficiency, and practical maintenance advice for homeowners across the Upper Ohio Valley. Read Alex Largent’s full bio to learn more about his expertise in the HVAC and Plumbing industry. Updated October 2025.
