In the near future I am going to be in the market for a new gas furnace and a/c unit for my house 1500 sq ft house (750 first floor, 750 second floor). I started to look at some of the major manufactures to see the differences between their models. What are good features to look for? For Example:
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Gas Furnace
- Multi-speed blower (3-4, 4-5) vs. variable speed
- AFUE 92% vs. 94% vs. 95-96%
- Nitrate Igniter vs. Silicon Nitrate Igniter
- Duel Fuel (gas & elec) vs. gas
A/C
- R22 vs. R410A
- Scroll Compressor vs. other compressors
Optional Equipment
- Humidifiers
- Filtration Devices
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I don’t mind spending a little extra money on a nicer unit; I just want to make sure I’m not wasting my money on features I don’t need.
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Any advice will be appreciated.
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Trevor
Replies
The installer is just as important as the unit. I would also consider a Hybrid Unit. It is a combination of a heat pump and gas or propane furnace. Heat Pumps are more efficient down to about 32F. Some units lower than that. At that point the gas furnace kicks in. I just did that myself. The exterior unit is two stage. Lower stage runs most of the time which is less costly and when needed the higher stage kicks in. The unit I bought was a Bryant only because the installer who I trust recommended it. He sells other brands also but said at the time it was the best value. Again find an installer you can trust and talk to him.
Varible speed blowers provide the best comfort and the greatest energy efficiency. They do so however at a greater cost. IMO, well worth the extra money.
AFUE - any of those are good. A top of the line gas funace will cost you several thousand dollars. The difference in a point or two in AFUE rating one way or another will never amount to much.
Ignighter? Really, who cares. The old ones lasted for decades and cost a few bucks at most. Unless messed with, not a problematic feature of the unit.
Dual fuel as in the hybrid someone mentioned is a good idea. You never know how the price of energy will evolve.
R-410a vs R-22. R-22 is the past, R-410a is the immediate future. Don't look back.
If you find a residential unit manufacturer that does not offer a scroll compressor, do not consider it further. I doubt you can find one.
Humidifers (a powered, computer controlled unit is the only way to go) may or may not be of any use in home and in your environment. I have one. If I lived in FLA, I would not.
Filtration - My personal preference is one of the large media mechanical filters, like the Honeywell, AirBear or AprilAir - whole house air filters.
Other features to consider - two-stage heat and two-stage AC. If available in the capacity you need, I would recommend both. I would also recommend a good, programmable digital thermostat.
In addition, if there is a stat that is matched to the system, get it. It is optimized for that system.
Great! Thanks for the info.
Trevor
Any furnace higher than 90% is a condensing style, high efficiency. Nuances in tested values may not really be meaningful.
Not sure what the guy said about variable speed fan ... cooling high, heating low ... that is normal. Variable speed in a mode may be more high tech than you need for a residence. Not sure what would control the speed.
Filters ... 2 inch pleated filters are better than the cheap filters you get at Lowe's.
You didn't mention where you are located ....
Heat pump MAY be good .... depending on your location.
Buy the most you can afford ... you'll have to live w/ it a while. More efficient means long term savings.
Not sure if I would install a humidifier in a residential system ... Don't know about this application. Maybe a stand alone unit if you need humidity? If humidity is desired in summer, consider a swamp cooler as an inexpensive cooling option?