location?

What are your rates, electric/kwh and nat gas/therm? Be specific.

Who is underwriting the labor warranty? While the ext labor warranty may provide peace of mind, it is my experience it is not worth it on a quality system. Remember though, it is homeowner's responsibility to see that new system is properly registered for warranty. Just read a horror story on a Carrier Infinity system where dealer and homeowner failed to register a system.

I can not see your ductwork. Other than age, are there known problems? Hot and cold spots? Leaks? Adequate returns? Have you been given a replacement cost?

The Amana Mdl number-APG15 or SPG15? Please check and advise.

On the surface, it appears Amana has a better warranty than Trane. This should be scrutinized closely especially understanding exclusions.

You are being quoted 3 ton units? What is heating output? Both the Trane and Amana have two stg gas valve that will require a true two stage thermostat to properly operate. The Trane has a var speed blower motor. Not sure if the Amana does. May be just a high eff motor but not var speed. This might be important for better dehumidification. You should check on this.

After further study, I think the Trane is a better unit with the var speed blower motor and two stage AC compressor. Amana warranty though looks stronger.

Post back.

IMO

http://www.amana-hac.com/Products/PackagedUnits/15SEERAPG15.aspx

http://www.trane.com/residential/en/products/heating-and-cooling/packaged-systems/xl16c-packaged-gas-elec.html

This post was edited by tigerdunes on Fri, Nov 7, 14 at 6:41

Thank you for the detailed reply. Here are the answers to your questions.

Location - I live in Charlotte, NC

Gas/Electric Rates - Electric 9.3587â / Gas 0.96839 per therm

Ductwork - 50 years old, hot and cold spots, leakage and lack of insulation. I have returns in every room.

Amana Model - The Amana is an APG15 (not SPG - sorry)

Warranty - Offered by J.B. and Associates. Cost is $610 to extend labor to 10 years

Additional Questions:

(1) Flex Ductwork - All 3 companies quoted flex duct. Is this a problem for a crawl space? Seems pretty standard these days, but a couple of the online forums suggest avoiding flex in a crawl.

(2) Returns - I have returns in every room. One company encouraged me to go to central returns, the other said to keep what I have. Suggestions?

(2) Amana APG15 - Any experience with this model? Price is about $1,000 higher. Trane is more of a known entity to me.

(3) Trane XL16 and XL 16-Dual Fuel - is one more reliable than the other? Seems like more to fail on the dual fuel.

Thanks!

Here is a fuel comparison between HP and nat gas.

Cost per 100,000 btu of useable heat

Electric baseboard: $2.48
Heat pump: $1.00
Natural gas: $1.18

As you can see, there is an advantage to a HP. Where you get hurt is the 80% eff on package units. Any opportunity to go to split system rather than package unit? You could then get a condensing furnace with 95%+ efficiency. My advice is to stay away from the heat pump because you live in an older home.

Who is J B and Associates? Third party warranties are problematic and i am generally opposed to them. I would forget the ext warranty and put that money toward a new ductwork system. Nothing wrong with flex as far your individual runs both supply and returns. But I would want metal for your supply and return trunk lines. R8 insulation minimum. Floor is insulated? Keep individual returns. You do want a box filter cabinet installed whether you replace ductwork or not.

I see nothing wrong with DF Trane model as far as reliability versus the straight 16c gas/electric model. I just don't think it's worth it taking into consideration your rates and location. Savings with HP when in use would be around 15%. You will have to be judge. If your home has poor to average insulation qualities, I don't think you would be happy with the HP.

IMO

I prefer the Amana design overall, because it places the heat exchanger before the cooling coil. It is just likely to last much longer that way. On Trane (and the majority of other units) you will get cold air blowing over the heat exchanger in the cooling season. This causes condensation on the inside of heat exchanger, which leads to rust, and eventually failure, often in under 10 years. However, the Trane does have a stainless steel heat exchanger, which will mitigate this somewhat. As tigerdunes said Trane does have advantages, with the VS blower and 2 stage cooling. If you decide you want those features, I would go with the Trane, as I'm pretty confident in their heat exchanger despite its placement. However, if you decide end up going with a simpler unit, I would take the Amana over Trane's offerings in that area.

Another one you could look at is YORK Affinity, they have both the heat exchanger before the coil, and 2 stage cooling/ variable speed blower. No dual fuel though.