Update
OK, I'm going lose any DIY and LBYM cred I had (short explanation below), but I'm going ahead with the highest level the guy quoted me, and I'm not going to bother with additional quotes.
With my previous DIY repairs, I was able to stretch this furnace out to last 24 years, and the A/C is older. I'm justifying a little 'splurge' for the best comfort level, and for that, I feel we need a 2-stage A/C, and that really requires a variable speed furnace - so it adds up. I'm also going with a new whole house humidifier (previous original unit needed repairs, and the new ones are easier to open for annual cleaning). And.... we are having the compressor moved from right near the patio and under the kitchen window, to the side of the house. And.... the water heater is the original - I can't believe this thing is still functioning from 1986! The replacement water heater has a powered damper, so that will reduce air infiltration. And of course the higher eff% furnace has PVC air in and out, so less air infiltration as well. Whew!
And it turns out, the difference between his 'good' and 'better' quotes was slight (< $200, main diff was 13 vs 16 SEER) - the various rebates offset almost all of the delta. And only the 'best' included the 2-stage A/C. And the 'best' qualifies for some added discounts and another $300 in tax credits (the key is a 13
EER - different from the
SEER rating - and only the Trane high end met that). And, at the high level, the difference in price between Trane and Amana (Goodman) looks like < $100 after tax adjustment, so I went Trane.
I was surprised, looking at the prices at Alpine ( alpinehomeair.com ), that going from the 80's% to 92% and to 96% actually had a pretty short payback of ~ 3-4 years, even with my stingy use of heat (turned way down at night, often low to mid 60's during the day when I'm home, maybe 68 in the evening). But there was also the comfort factor (2 stage A/C to reduce humidity and handle the hottest days, and variable speed fan for better circulation). I didn't really do the same comp with these quotes, as the higher eff% was really tied into the comfort requirements I set.
About $1400 delta (before Fed tax credit/deduction) to go up to the 2-stage A/C and higher level furnace to support that. There will be some offset in lower bills, and if the unit lasts 14 years (it should - just easy math), that's roughly $100 per year amortized, less with gas/electric savings.He took room sizes, vents sizes/amounts/ orientation, some estimates of insulation. I had told him our 80% 125,000 BTU furnace didn't seem to run much past ~ 2/3 duty cycle in even the coldest weather, and he came up with 100,000 BTU of the higher eff% models, so that makes sense to me.
Back to some aspects of my OP, yes, I still think Goodman makes a lot of sense for a DIY, but this was a big job, more than I wanted to tackle. For a basic furnace replacement, w/o having to dink with the A/C, a handy DIY would probably be well served by the Goodman, IMO. And it appears the price delta between Goodman/Amana and other brands becomes less the higher up in features/eff% you go.
I've had a lot of responsibility for extended family this past year, and it has made it near impossible to devote large blocks of time to any project, so just no way will I DIY this one (I probably wouldn't anyway - this is a big job, moving compressor, running new PVC in/out), and no, I'm not even going to spend the time/effort for multiple quotes. I got a good feeling from this guy, no pushy sales, he really knew his stuff, considered a lot of alternatives and options, and they got good reviews on-line, and we got a good reference from a friend. Tha'ts more important to me than some $ difference. At this point, I'm 'applying' all my past 'scrimp-and-save' tokens to this job. Rationalization mode ON.
And of course, I'd like to get this done before the next heat wave, or company comes during even a warm spell.
Install is next Friday, looks like we won't have too much hot weather before then, and the nights stay cool, so that helps.
Only downside other than $$$ (and he laughed at me for this) - I have to give up my old-school mercury Honeywell thermostat!
The two-stage looks at temperature deltas (though it can be set up for a timed function I think). Just like volume controls on audio gear, I like to just turn a knob, not push buttons up and down. Hopefully the UI on the thermostat is good, and cranking up/down a few degrees, or 10 degrees at night is easy (no, I don't use timed or 'learned' functions - I don't have a schedule to learn).
I guess I should have done a tl;dr version, but I didn't. Hah!
-ERD50