Olsen Ultramax III Furnaces | Reviews | FurnaceCompare®

Olsen Ultramax III Furnace Overview

Olsen’s Airco UltraMax III furnace is a 95-percent AFUE furnace. Due to its flexible installation configurations, this compact unit can be adapted to fit in small spaces. It requires only 2 inches of clearance in the front of the unit; the placement of various outlets such as the condensate drain, electrical connections, air inlets/outlets and gas supply piping can be custom arranged.

The UltraMax III is equipped with a tubular heat exchanger that the manufacturer says is capable of lasting longer than others due to a wrinkle design that protects the bends from thinning over time. The induced draft fan requires no oiling and has sealed ball bearings for increased longevity.

The internal parts of the UltraMax III are encased in a tightly sealed, insulated cabinet. The front panels can be removed for access to the burners and controls, and the aluminized steel base provides protection from corrosion.

In addition, the furnace is designed to exceed ANSI safety requirements. The unit has an overheat limit as well as shut-offs for the main gas valve and vent in case of a blockage. Prior to shipment, each furnace’s safety features are tested under conditions comparable to those after operating for about 20 years. The unit is delivered ready to accept air conditioning, a humidifier and an electric air cleaner and, finally, the included Honeywell Smart Valve II helps maintain precise operation and troubleshoot in the event of needed servicing.

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Consumer Reviews of Olsen Ultramax III


  • Very Satisfied
  • Somewhat Satisfied
  • Neutral
  • Somewhat Unsatisfied
  • Very Unsatisfied
  • #2 of 3 Olsen Furnace
  • 66.67% of customers recommended

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Olsen Ultramax III Furnace Reviews

"Olsen Ultra max III now 14 years old, first issue."

5.0 rating
Very Satisfied

I have no complaints about this furnace that has given 14 years of reliable service. Very low maintenance required on this unit. Fan motors all sealed and perm lubed. I have done regular filter changes and a yearly clean. But it’s just a machine and yes it did fail a few days ago… on New Year’s Eve. Luck is with me so far as the outdoor temps are mild enough that I can wait for the trades to re-open Jan 3 to call for local service. Description of Issue: Furnace vent blower will go on for a short while, but no burner action and then the vent blower turns off. Best guess is a pressure switch or igniter has died. I’ll update this review after I get the service tech in for a look and make the repair.

Ontario, Canada

"I hate my furnace"

1.0 rating
Very Unsatisfied

I purchased this Olsen furnace 6.5 years ago and I wouldn’t give it to my worst enemy. Every year it fails on me. It shuts off for no reason, then you need to either take it all apart and grease the fans or the igniter needs to be replaced. Well, it’s failed again and now I can’t get a darn part for it near my home because not even the repair people around here want to work on them. I wish I would have done a lot more research on this before sinking this kind of money into a friggen lemon.

Ontario, Canada

"29 Years Service"

5.0 rating
Very Satisfied

We just replaced our 1984 model Olsen furnace. It was still working very well but not very efficient and our a/c was on its last legs so we replaced both. All we ever had to do with the furnace was replace the blower motor 12 years ago. We had trouble finding an Olsen dealer in our area and went to a local company that sells Lennox products. I hope Dave is as good as Olsen.

Brantford, Ont.

Other Ultramax III Reviews

There are few reviews of the UltraMax III furnace itself on online discussion forums. However, homeowners have posted comments online about how pleased they are that replacements parts, such as the draft inducer blower, are easy to find online.

Olsen Ultramax III Model Numbers

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

Model Number AFUE BTUs per Hour
GTH-050 94 50,000
GTH100 95 100,000

Ultramax III Warranty

This UltraMax III furnace comes with a lifetime warranty on the heat exchanger and a 5-year warranty on all other parts.

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