My current furnace and A/C are over 20 years old and getting very noisy, so I suspect that they are about due for replacement. I've never been very happy with my current furnace and A/C with their single stage blower - temperature varies a lot and distant rooms are always cold in winter and hot in summer. With rising energy costs I'm getting nailed for $400-500 per month for gas in the coldest winter months, so I figure that a new high efficiency furnace will pay off fairly quickly. However, I'm less certain about whether to get a heat pump or a conventional A/C, as we spend much of the summer at our vacation cottage and leave the A/C at home set at 80 degrees while we're away. Our summer electric bills run about $150-200 per month. Our house is a 1 1/2 story contemporary design with 3200 square feet of floor area.
A local Carrier dealer has recommended an Infinity ICS 58MVC120-1-20 (120,000 BTU) furnace and either an Infinity 16 25ANA660 A0003 heat pump or an Infinity 17 24ANA760 A003 air conditioner. The premium for the heat pump over the A/C is $1700. His calculations indicate that either option should pay off in 6-7 years vs. my current system, but he recommends the heat pump because of higher expected increases in fossil fuel prices.
I have several concerns that I hope this talented group can help me to resolve:
- Is an air heat pump really practical for southeast Michigan? Are the energy savings vs. a conventional A/C significant? Will it deliver the same heating comfort as a furnace?
- As it runs basically all year, will a heat pump fail more quickly than an A/C which only runs in the summertime?
- Do I need a top of the line Infinity ICS furnace paired with a heat pump or would a lesser model do the job? I like the blower speed and burner flexibility of the ICS, but it will (hopefully) not be providing much of my heat in spring and fall, so maybe it's overkill...
- Initial cost is less of a factor than the operating cost, ultimate comfort level, and reliability of the system, but I don't want to buy a gold-plated system that is beyond my needs.
Any thoughts or suggestions would be very welcome.