The Goodman GMH8/GDH8 is a multi-speed, two-stage gas furnace with an efficiency rating of 80% AFUE. It is designed for multi-position installation — the GMH8 is an upflow horizontal unit, and the GDH8 is a dedicated downflow unit. It reduces energy usage by operating on low speed up to 90% of the time, while the multi-speed blower and two-stage gas valve help reduce noise levels. The unit features a tubular aluminized steel primary heat exchanger, along with an electronic control board with self-diagnostics and a left or right connection for gas and electric service. The heavy-gauge steel cabinet has a baked enamel finish and is fully insulated to improve efficiency while reducing sound levels.
Heater is a waste of money. Had it 2 winters, it broke 11 times. Had it repaired each time and something else was wrong. Have had no heat 11 times in 2 winter seasons. Broke again; it’s a lemon. Don’t waste your money, the company doesn’t care.
"Good dependable furnace"
We had this furnace installed in September of 2006 and have had zero problems with it. We went with a local, very well known and dependable company who, in a small town, have to maintain their reputation. The only service, if you can call it that, that’s been done is to properly clean the electrostatic filter monthly. The furnace heats our century- old house easily and we’ve had two consecutive horribly cold and windy winters here in west Michigan.
"No more Goodman heaters for us"
Bought this heater in 2008 and it started acting up in 2011 and has not worked properly since. Luckily, I have a service contract with the contractor who installed it. We have had the control board and igniter replaced several times – many times within the same year. I do not feel comfortable at all with this heater since it is so unreliable.
"Not a happy camper"
This natural gas furnace has worked well for 5-plus years. Now it cycles on and off multiple times and wont stay on long enough to warm my house. I called Goodman Manufacturing, only to find out my 10-year warranty is really only 5 years because I did not send the registration card by registered mail. I was not told by the installer that it had to be done online in 60 days or sent by registered mail. In California this would be illegal! (I live in Virginia now). I am pretty sure I can fix this myself, but that is not the point. What about next time? A lot of the reviews talk about frequent control board failure and that sounds like a lot of money. The unit is in my hallway and is very noisy and I don’t want it to run hot so I’m stuck with the noise. The warranty issue sticks in my craw and you can be sure I will never buy a Goodman product again and would never recommend it to anyone I liked!
"Goodman furnace delivered powerful heating when we needed it. I would recommend it to a friend."
Got this furnace in my cabin before I moved in. The furnace has been in the cabin now for at least four years. I love the way that it heats up the house so rapidly, and always works whenever I need it. It is powerful enough to heat all rooms in the cabin, even rooms without vents heat through convection because this baby is so powerful. I like also that this furnace is relatively quiet. I also liked that this furnace was really affordable, and I only had to pay about 12$ a month when I first got it. Never had to replace any parts, the only thing I do not like about this furnace is that sometimes I have to relight it manually, because it randomly cuts off on rare occasions which is strange. However, after relighting it goes right back to normal. Even though that happens though, overall I would highly recommend this furnace, you certainly will not freeze while you have this in your home.
A consumer on hvac-talk.com choosing between the GMH8/GDH8 and a comparable Rheem unit asked for opinions on which furnace was better. A slight majority chose the Rheem, with a few professional members listing the low quality of Goodman and the quality of the compressor as reasons not to buy it. Those in favor of the GMH8/GDH8 included professionals who stated they have had no problems with the unit and most problems are due to installer error, not the quality of the furnace.
Goodman GMH8/GDH8 Model Numbers
The GMH8/GDH8 is available in different models which vary in efficiency and capacity.
BTUs per Hour
Product registration is required for maximum warranty coverage. The Goodman GMH8/GDH8 furnace warranty is comprised of the following:
10-year unit replacement limited warranty
Lifetime heat exchanger limited warranty
10-year parts limited warranty
Labor costs are not covered by the warranty. If the unit is not registered within 60 days of installation, Goodman will offer a 20 year warranty on the heat exchanger and 5 years on all remaining parts.
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