Goodman reports that its GKS9 gas furnace was built for reliability and efficiency. Its dual-diameter tubular heat exchanger is crafted from aluminized steel and uses a “wrinkle bend” technology, which the manufacturer says adds to its durability. The furnace control board is self-diagnostic and has a low-voltage terminal block for easy control of the unit. This model features a 4-speed circulatory motor for uniform heating and a single-speed induced draft blower, which assists in the energy conservation aspects of the furnace. The blower is sound-isolated. The Goodman GKS9 gas furnace has a single-stage combination redundant gas valve and holds a 92 percent AFUE rating.
The corrosion-resistant cabinet is designed for upflow installation, but it can easily be converted to a horizontal left or right position with a pressure switch kit. The bottom of the cabinet is constructed with airtight solid steel for enhanced return applications from the sides.
I’ve owned a house with one of these since early 2011, which had this unit installed when built in 2007. In 2014, the control board failed, then the draft inducer motor in 2015. It has been reliable since those issues; the other portion of this dual fuel split system is a York Affinity 5t heat pump. I suspect the draft inducer motor failure may have been accelerated due to an incorrect heating cph setting in the thermostat, which had been left at the default for a standard efficiency furnace resulting in more frequent cycling. Reducing the thermostat’s cooling cph setting by one step also improved both the efficiency of and dehumidification by the heat pump, bringing humidity down ~5% to an ideal state in the mid 40’s. The contractor’s installation had a fair amount of air leakage from its seams, which I mostly fixed with foil tape within the last year, but I recently found this furnace has significant vacuum leaks from the lower blower section’s service door. Considering it has no gaskets on the door, I was surprised to see its marketing claim of < 2% cabinet air leakage. The leakage from the bottom of the door was most significant, and I used a combination of adhesive weatherstripping foam on the sides and removable / no residue tape along the bottom seam to properly seal the cabinet door.
West Coast, BC
We had this furnace installed by the builder of our new home and it is a pain in the butt. It will take up 45 minutes to bring the temperature up one degree. Service guy checked it out and said Oh, it’s working just the way it’s supposed to. If that’s the way it’s supposed to work then it’s a long way from being energy efficient. I wouldn’t recommend this piece of crap to anyone.
Saskatoon, Saskatchewan, Canada
"Worst furnace ever — Lemon"
Purchased furnace and used for 2-3 months for first winter. Did not use it for AC. Second winter it turned on but did not work. Replaced the circuit board and then a loose wire and used for 3-4 months that winter. Third winter, limit switch was replaced and it worked one day and here I sit again and the furnace is not working. The furnace does not have even 12 months of use. Goodman furnaces are lemons! I am going to contact Better Business Bureau, Goodman, Homebuilders Association, Realtors, etc.
"Warranty, or lack thereof.."
Purchased a new construction home (1st and only owner of the home) with 4 Goodman units (2 furnaces and 2 A/C units). Neither the builder nor the installer registered the units when the home was built. When I called customer service and explained my case regarding the failure of parts in one furnace, I was essentially told nothing could be done to warranty parts at this point because it needed to be done in the first 60 days of installation. I would have thought the company would have honored the warranty of 10 years (or even 5 years with a one time exception rule) on parts as per their claims regardless of the non-registration considering the circumstances that the builder and installer dropped the ball on the registration. Had someone informed me, I would have certainly registered the product to meet this ridiculous requirement of a 60 day period. Not only will they not warranty the parts now, but also told me there is nothing they can do going forward. Essentially, I’m on the hook for any part failure for the next four years as well. Terrible customer service…you should stand behind your products and not hide behind warranty deadlines! Either you have faith in the quality of your products or you don’t. Goodman is missing the bigger picture here! Disappointed to say the least.
"Eight years later"
This is my second review. After 8 years something finally broke, the control panel. It was covered. I paid $85.00, which I would have spent anyway on the fall checkup. The part was covered, no problem. I still think with any furnace the install is the key. Goodman is a low cost no-frills furnace, a good value. By the way, my installer said he does more service work on Trane than Goodman.
A review on furnacereviews.com relates the GKS9�s inconsistency in heating performance. These heating variations appear to be more inconsistent during extreme winter conditions, according to the reviewer. Unfortunately, the reviewer on this forum has no clear-cut solutions to addressing this issue, other than staying on top of regular maintenance.
Some consumers also have complained about the system malfunctioning due to improper installation or maintenance by inexperienced technicians. For example, a consumer posts on justanswer.com a question about the unit�s limit switch, which turns out to be difficult to reset. The homeowner suspects the problem began when a technician replaced the unit�s blower.
Goodman GKS9 Model Numbers
The GKS9 is available in different models which vary in efficiency and capacity.
BTUs per Hour
The warranty for the Goodman GKS9 gas furnace is the baseline standard for all Goodman furnaces: a 10-year parts warranty. In addition, the original registered owner of the unit is entitled to receive a new heat exchanger if the unit fails under any circumstances for as long as he owns the home. Warranty registration must take place within 60 days of the unit being installed.
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