Have you reviewed the Manual J calculation? I find it hard to believe that a 2750 sq. foot new construction house needs 6.5 tons of cooling. Something is not right.

I will assume your new home will have excellent building/insulation qualities. If basement is insulated and below grade or even partially below grade, it will have small heating and cooling load. I don't like the way either dealer has sized you. Have you received in writing a load calc for each zone. If not request one. I might consider using zoning control for the main floor/basement zone. The equipment quoted is the XR series, exact same available from AmStd. All excellent choice especially for heat pumps. Thermostats do matter. Wouldn't have the models the Trane dealer quoted. Regardless, I would want pleated filter media cabinets for each system. I like the AmStd quote the best especially with the 2 stage HP condenser for the main floor/basement. I would though look into zoning control for that system.

IMO

Mike_home & Tiger,

the basement is a walkout and all exterior walls are insulated. I have better quality vinyl Windows and R50 in the ceiling.

I have only seen the totals from the manual j not the actual breakdowns by floor.

I was told by Am Std that the unit quoted didn't come in 1/2 ton increments which is why a 4 ton was quoted.

i will ask for the complete manual J calc and come back with those numbers.

I will also ask for a quote for a zoned system as well.

Thanks for the advice so far.

cntrybmkn

Mike_home & Tiger,

the basement is a walkout and all exterior walls are insulated. I have better quality vinyl Windows and R50 in the ceiling.

I have only seen the totals from the manual j not the actual breakdowns by floor.

I was told by Am Std that the unit quoted didn't come in 1/2 ton increments which is why a 4 ton was quoted.

i will ask for the complete manual J calc and come back with those numbers.

I will also ask for a quote for a zoned system as well.

Thanks for the advice so far.

cntrybmkn

cntrybmkn,

I just want to give you a point of reference ....Your home could be completely different than mine, but I'm in a 2400 sq home.. Not including a 1200sqft basement... Built in 2004 in MD, near the PA line... At the time of build, it was a EPA energy star home. I do heat the basement in the winter, but do not cool it, in the summer... I just close all the basement vents in the summer.

In it, I've got a 3.5 ton AC and a 100K propane furnace.. The AC is more than enough to keep my place cool, even down to 68F on days where it hits 100F. Furnace is way more than enough.. It's over sized... I don't have any zoning, but I do have returns in every room. Even without the zones, no one has ever say the top floor was to hot or cold, compared to the main floor.

Based on my place, with just a 3.5T AC, I'd say the 6T for AC is over doing it...

For crab,,,glad you recognize your furnace is oversized...is your furnace single stage or two stage?...

TD

Furnace is single stage ... It's a York Diamond 90.. with either 92 or 93% efficiency... Can't remember.

I'm replacing my AC with a heat pump because the AC compressor doesn't sound right and propane prices have been killing me. I'm keeping the furnace and going to a dual fuel setup... The plan is to use the heat pump down to 35F (outside temp) but below that, to use the furnace..

Sounds like a good plan....you will need a DF thermostat and I recommend an outdoor sensor so you can control the changeover between fuels. Outdoor sensor should be located in complete shade.

IMO

I picked up a Honeywell Prestige IAQ.. I was thinking about putting the outdoor sensor under my porch roof or bay window..