Lennox G40UH Furnace | Reviews | FurnaceCompare®

Lennox G40UH Furnace Overview

Filters for the Lennox G40UH

Air Flow ConfigurationCabinet WidthFilter Size(s)
All14.5″14x25x1 (bottom)
16x25x1 (side)
All17.5″16x25x1 (side)
16x25x1 (bottom)
All21″16x25x1 (side)
20x25x1 (bottom)
All24.5″16x25x1 (side)
All24.5″24x25x1 (bottom)

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Consumer Reviews of Lennox G40UH


  • Very Satisfied
  • Somewhat Satisfied
  • Neutral
  • Somewhat Unsatisfied
  • Very Unsatisfied
  • #12 of 29 Lennox Furnace
  • 28.57% of customers recommended

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Lennox G40UH Furnace Reviews

Showing 1-5 of 7 reviews


5.0 rating
Very Satisfied

After 11 years only thing bad that happened was outside fan bearing failure.Easy to replace,but I cannot buy Lennox parts because not certified.Picked it up at WW Grainger.

D Wilder

"Many many service calls"

1.0 rating
Very Unsatisfied

This system is made so cheaply. Strongly I do not recommend to anyone to use. Too may fails because of poor quality. I lived in 4 houses, and used all different systems, but Lennox this model only fails all the time and have to pay $$$ every time I call the service.

Kennesaw, GA

"My Trusty Furnace"

5.0 rating
Very Satisfied

I have had my furnace for over 10 years now. It was installed 3 years before I bought the house, so it is over 13 years old now and I have never had a problem with it. The furnace was made by Lennox. It is a hot air furnace that uses natural gas and is of sufficient capacity to heat my whole house even in the coldest of weather. The furnace is of pleasant appearance and simple design that requires very little maintenance. It is located in a closet in my basement next to other major appliances. I once had a maintenance man come in to check the furnace out. There was nothing wrong I just wanted to know if it needed maintenance or adjustments. Nothing was needed so now all I do is change the air cleaner every 3 months. I like it because I never had any problem with it. If it ever needed replacement I would buy the same brand again and I would certainly recommend it to a friend.

Walled Lake, MI


1.0 rating
Very Unsatisfied

What a joke! This is the 2nd Lennox g40uh-24a-045x* furnace that we have purchased in the last 15 years. You think that we would have learned after the 1st time. Once again the furnace is running continually and it will not shut off. Last time the furnace would not turn on and they told us it would be cheaper to buy a new furnace then replace the circuit boards. Ha ha! I will never purchase another Lenox furnace. They are a piece of junk and the company should be investigated for selling inferior products. If you are thinking about purchasing a Lennox product don’t!!!

[email protected]

"Continual Break Downs"

1.0 rating
Very Unsatisfied

We have a g40uh gas furnace installed in late 2005. I have just made my 4th service call due to a wire coming loose causing the fan to not start. While seemingly simple due to the cheap parts in this model, it will not stay fixed and short of spending thousands for a new unit Lennox has no solution. I was happy to see a Lennox unit but now am wondering if the former quality of the brand is long gone.

Other G40UH Reviews

Lennox G40UH Model Numbers

The G40UH is available in different models which vary in efficiency and capacity.

Model Number AFUE BTUs per Hour
G40UH-36A-070* 80 66,000
G40UH-36B-090* 80 88,000
G40UH-48B-090* 80 88,000
G40UH-48C-110* 80 110,000
G40UH-60C-110* 80 110,000

G40UH Warranty

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