How do they actually differ?
A gas furnace creates heat by burning fuel. A heat pump does not create heat at all — it moves heat, extracting it from outdoor air and concentrating it indoors, which is why it can deliver more energy than it consumes. In summer it reverses and works as your air conditioner.
That difference drives everything else. The furnace's output is essentially constant regardless of outdoor temperature; the heat pump's output and efficiency both decline as it gets colder, because there is less ambient heat available to move.
Which costs less to run in central Iowa?
It depends on outdoor temperature and on the ratio between your electric and gas rates. Above roughly freezing, a modern heat pump is typically the cheaper way to heat. As temperatures fall toward the single digits, its efficiency drops and natural gas generally becomes the better value.
Because Iowa gives us a great many hours in that mild band and a real stretch of genuine cold, neither wins outright across a full season. That is precisely the case dual-fuel is designed for, and it is why we set the switchover point from your actual MidAmerican Energy rates rather than a factory default.
Where each one wins
- Heat pump: shoulder-season efficiency, October-December and March-April
- Heat pump: one outdoor unit covers both heating and cooling
- Heat pump: no combustion, so no flue and no carbon monoxide risk from heating
- Furnace: dependable full output on the coldest January nights
- Furnace: warmer supply air, which many people prefer at the register
- Furnace: lower installed cost and simpler service in most Des Moines homes
Do heat pumps really work in Iowa winters?
Cold-climate models genuinely do work far below what older heat pumps managed — many maintain useful capacity down into the single digits and below. The outdated advice that heat pumps are useless north of Missouri no longer reflects the equipment.
The caveat is capacity, not capability. As it gets colder, a heat pump's output falls exactly when your home's heat loss is highest. Without a gas furnace as backup, the system falls back to electric resistance heat, which is effective but expensive. Read a cold-climate unit's rated capacity at 5°F, not just its HSPF2.
How should I decide?
Start with what you already have. If you have natural gas service and a furnace that is failing, replacing the furnace and adding a heat pump in place of an aging air conditioner gives you dual-fuel for close to the cost of doing both separately anyway.
If you do not have gas service, a cold-climate heat pump is very likely your best option and will substantially outperform electric resistance or propane. If your furnace is young and healthy and only the AC needs replacing, a heat pump as that replacement is worth pricing. We will run the comparison for your rates and your house — and if a straightforward furnace and AC is the better value for you, that is what we will say.
Frequently asked questions
Will a heat pump keep my house warm at -10°F?
A cold-climate heat pump will still produce heat at that temperature, but at reduced capacity, and in most Iowa homes it will need backup to hold your setpoint. That backup is either a gas furnace in a dual-fuel setup or electric resistance heat. Planning for the backup is part of designing the system, not an admission the heat pump failed.
Is heat pump air really cooler than furnace air?
Yes. A heat pump typically delivers supply air in the 90-100°F range, while a gas furnace delivers noticeably hotter air. Both heat the house effectively, but heat pump air can feel cool against your skin since it is near body temperature. Most households acclimate within a season, though it is worth knowing before you buy.
Does a heat pump replace my air conditioner?
Yes — a heat pump is an air conditioner that can also run in reverse. If you install one, you do not keep a separate AC. That is a large part of why the incremental cost over a straight air conditioner is smaller than people expect.
Which qualifies for better rebates?
Heat pumps have generally been the focus of federal tax credits and utility incentive programs, often with meaningful amounts for qualifying efficiency tiers. Programs change annually, so we check current MidAmerican Energy and federal offerings during the quote and handle the filing.
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