Before we talk about brands and products at all, which contractor examined the ductwork (size, returns, supplies, etc.) and performed a Manual J load calculation to determine sizing? You cannot go by square footage or guess or you may sacrifice your comfort.

Carrier vs. Lennox? Can't go wrong with either one in my opinion.

Please provide the model numbers for the indoor units. Variable speed is definitely worth it in my book. Also, I am highly doubtful of those SEER and HSPF ratings that you posted. They almost sound like those "up to" values. I can confirm them for you on ARI's directory.

What thermostat? If not going with the Infinity, I would certainly go with the Honeywell VisionPRO IAQ and have it set up to control the dual fuel system and dehumidify on demand (with variable-speed blower).

Thanks for the quick response. Believe it or not, both contractors took the measurements and did a Manual J, which is why they are both finalists.

You are right about the quoted SEER and HSPFs, they are the up to numbers (I fully recognize that we will not see the full value- old house with old ducts). Full Carrier install would be infiniti. The lennox dealer did not specify which thermostat(thanks for the recommendation).

Sorry, but I forgot to address your question about the furnace- Carrier unit is 58VMR/58VLR. Lennox is 023V. Both oil (unfortunately we do not have gas service on our street).

Last I heard the oil furnace can't interface with the Infinity system. Yep, I just changed Carrier's website and they have a Performance 80 oil furnace that is not listed as supporting the Infinity controls. That would be a big downside to me, so I'd look at the Performance 15 heat pump, variable-speed oil furnace backup, and VisionPRO IAQ thermostat. That would be a nice system. That, or an equivalent Lennox system.

Excellent catch, thanks! Does the pricing look reasonable for the type of system being installed. The Lennox quotes, in particular appeared to be fairly high.

snrub

this is one system? I would carefully weigh the dual fuel with oil backup vs a straight high eff HP with matching var speed air handler. oil prices just scare me!

and you might ask dealer about the feasibilty of zoning controls for the first and second floor to improve overall comfort and good temperature control between the floors.

Carrier Infinity would be my preferred choice.

IMO

The prices do seem a bit high, but since they're relatively consistent, it could just be the circumstances for your installation or just your area. Are you stuck on keeping the oil furnace? A high-efficiency heat pump with backup electric heat might be a better alternative--Carrier's Infinity 16 heat pump would be my recommendation.

We are not, in fact, particularly wedded to the Oil furnace (in retrospect we should have checked to see if we could switch to gas before buying the place). Backup electric may very well be an option. I will look into it. Thanks again for the input!

snrub

run the numbers on attached fuel comparison calculator.

check with electric utility on any special rate incentive for HP heating with electric backup.

and again if this was my home,I would strongly urge you to discuss feasibility of zoning controls for the first and second floor for best comfort and temperature control.

and I agree with Ryan that the Infinity 16 HP would be a great unit.

IMO

Here is a link that might be useful: Fuel Comparison Calculator

Thanks. Inquiries are already out to the bidders to see what they can do on a new air handler w/ electric strip heat.

We have looked into zoning, but that part of the project will have to wait for stage 2. Given the configuration of the ducts, estimates ranged from 7-10 thousand. At those prices, it may be better for us to put in a separate system to service the second floor, since that will also give us the option to heat/cool the attic when we finally get around to finishing it (3-5 years down the road).