The Lennox G50UH gas furnace is not currently produced by Lennox; the latest available owner’s manual lists the year of production as 2000. The G50UH is part of the Lennox Elite series, and can achieve an AFUE of 80 percent. The heat exchanger is constructed of aluminized steel, and the blower compartment is insulated for quiet operation. The low-speed fan circulates air constantly for more comfort. Lennox products are designed to work together as an integrated system to provide uniform temperatures and healthy air quality.
We bought and installed this furnace in 2000. After 17 years of reliable service I can say I am completely satisfied. I called a service tech once who did something with the flame sensor. A few years later I just cleaned it myself. Now I’m replacing the draft inducer motor. Now, with 17 years of use its coming close to the end of a furnace’s useful life, so its coming time for another furnace. But I won’t buy it until absolutely necessary. And yes, I would buy another Lennox furnace.
"Flame Sensor Replaced 3 Times"
We had this Lennox G50UH-36A-070 installed in August 2005. Since then, we have had 5 service calls all because of no heat. All related to the flame sensor which has been replaced 3 times in that period. Until today, I did not realized how common and widespread this problem is. Not a good product by a country mile. What a turkey!
"Dissatisfied Lennox customer"
New house, Lennox furnace and heat pump: the heat pump fan went out at four years (part warrantied, I paid labor); then at five years and seven weeks the pressure switch (all my cost) and five years 11 weeks the circuit board (over $400, again, all my cost). Never again.
We have had this Lennox furnace G50UH-36B-090-07 for three years and has given nothing but trouble from noisy fan motor to bad gas ignition to flame sensor cleaning. Wish I had my old furnace re-installed as this was absolutely trouble free for almost twenty years. Having a trouble free furnace gives peace of mind especially when going on vacation as the winters here range from minus 5c to minus 40c. If you are thinking of purchasing a new energy efficient furnace I would not be looking at Lennox as their replacement equipment is very excessive in costs which by the way they call “maintenance” !!
Other G50UH Reviews
Most of the talk on the forums about the G50UH seems to be about ignition problems; either the furnace will not light or ignites and then goes out. For example, a thread on diychatroom.com reveals a discussion of a Lennox G50UH that will not light. The experts advise cleaning out the vent pipe and the draft housing.
A post on doityourself.com details a similar problem a homeowner is having with his Lennox G50UH furnace. The flame goes out occasionally, and the homeowner has tried several solutions listed in the owner's manual. The last suggestion he mentions is to clean the flame sensor with steel wool, which he has not tried yet. The experts respond that this often solves the problem.
Another Lennox G50UH owner posts a question on justanswer.com about his furnace not staying lit. The online contractor leads him through a series of steps to test for the problem. The contractor concludes that the problem is in the thermostat of the outdoor unit.