Start with two separate numbers: the full installed price and the annual cost to heat your home. Compare the same rooms, comfort level, and work scope before subtracting a verified rebate.
What changes the installed price?
A system serving a few rooms and a whole-home project are different purchases. A useful quote begins with an assessment of your home and names the equipment and work included. A price advertised per indoor unit cannot establish the total for your property.
The system and the home
- Heating needs: the rooms to be served, the home's heat loss, and equipment performance in local winter conditions.
- Equipment and distribution: outdoor and indoor units, their exact model numbers, controls, and any duct alterations.
- Installation route: unit locations, refrigerant-line routes, outdoor supports, drainage, and access to the work area.
The supporting work
- Electrical work: circuits and disconnects, plus any panel or service work an electrician determines is needed.
- Other project work: permits, removal of old equipment, and wall or ceiling repairs.
- Completion and support: system testing, an operating demonstration, warranty terms, and service availability.
Ask which insulation or air-sealing improvements should be considered before final equipment sizing. Have a qualified professional assess electrical capacity; a panel upgrade is not automatically part of every heat-pump project.
Background: ENERGY STAR buying and installation guidance ↗ and electrical-readiness guidance ↗.
Get inclusions and exclusions in writing
Use these questions to uncover differences between bids. Each item may be included, excluded, or priced as an allowance; ask for its status and who will do the work.
- Electrical and permits: Does the total include the electrician, permits, and inspections? Is possible panel or utility service work separately quoted?
- Mounting, lines, and drainage: Are supports, line covers, condensate routing, and any needed drainage equipment included?
- Ducts and finishing: Does the price cover specified duct work, sealing, wall repairs, painting, and cleanup?
- Existing equipment: What stays, what is removed, and who handles disposal? Ask how the proposed heating plan affects any system you retain.
- Testing and aftercare: What checks and homeowner instruction are included? Separate equipment warranty, labor coverage, travel charges, and scheduled service.
- Changes and payment: What could change the price after work begins? Require written approval for extra work, and compare the payment schedule and any financing fees.
Record each installer's answers in the quote-comparison worksheet →
Compare the combined annual heating cost
When a heat pump replaces oil or propane use, electricity use rises while fuel use falls. A higher electric bill alone cannot tell you whether total heating costs went up or down.
Use the same rooms, indoor temperatures, and weather assumptions. If a heat pump serves only part of the home, include the fuel or electricity still needed elsewhere. Separate domestic hot water from space heating when the same fuel supplies both.
For an operating budget, add estimated heat-pump electricity, remaining heating fuel, and any other heating electricity. Include service and repairs separately. For a full household budget, also account for summer cooling, fixed utility charges, and loan payments.
A heat pump provides summer cooling as well as heating. Added cooling is an additional use to budget for if your home did not previously have air conditioning; better comfort can be valuable even when it does not reduce spending.
Sources: Efficiency Maine's energy-bill explanation ↗ and ENERGY STAR heat-pump overview ↗.
A worked example: fuel avoided versus electricity added
Illustration only: assume an installer estimates that 6,000 kWh of annual heat-pump electricity will replace 600 gallons of space-heating oil for the same heating job. Use a hypothetical oil price of $3.50 per gallon. These are invented inputs to explain the arithmetic, not current Maine prices, a typical home, or a prediction for your system.
At an assumed electricity price of 25¢/kWh
- Oil expense avoided
- 600 gallons × $3.50 = $2,100/year
- Heat-pump electricity added
- 6,000 kWh × $0.25 = $1,500/year
- Difference in heating energy cost
- $2,100 − $1,500 = $600/year less
| Electricity price | Heat-pump electricity per year | Heating energy cost difference |
|---|---|---|
| 20¢/kWh | $1,200 | $900 less |
| 30¢/kWh | $1,800 | $300 less |
| 40¢/kWh | $2,400 | $300 more |
This compares only the oil replaced with the electricity added for heating. It excludes installation, rebates, financing, service, repairs, cooling, fixed charges, and changes in other heating use. It does not estimate kWh from gallons: the installer must justify both quantities using the home's load, existing-system efficiency, heat-pump seasonal performance, and expected coverage.
Build an estimate with your own inputs
- Gather a full year of bills. Record fuel quantities and prices, electricity use, and any water-heating or cooling use that needs separating.
- Define the proposed coverage. Ask which rooms and heating loads the system will serve and what heating use remains.
- Open Efficiency Maine's comparison tool. Choose the row for your current heating system, update fuel prices, and review efficiency assumptions under “Show Details.” Calculate, then use Increase/Decrease to bring its annual cost into line with your current heating cost. Compare the applicable heat-pump row at that heating demand.
- Review assumptions with the installer. Ask whether the tool's system and distribution efficiencies fit your home. A rating at one outdoor temperature does not establish seasonal electricity use.
- Try a range. Change fuel prices, electricity prices, and seasonal performance assumptions. Keep the heating demand comparable; allow separately for cooling, retained heating, and service.
Open the official heating-cost calculator ↗
Use your applicable electricity supply and usage-based delivery charges, not just the supply price. If comparing utility rate plans, also compare annual fixed charges. The calculator's defaults are comparison assumptions; replace them with prices and efficiencies appropriate to your situation. Actual performance can differ.
Method and tool instructions checked against Efficiency Maine's calculator ↗ on October 11, 2026.
Bring the costs together before choosing
Compare the full installed prices for equivalent scopes first. List verified rebates separately, including eligibility, payment recipient, and application timing. Check the current program terms before counting an incentive in your budget.
If borrowing, compare interest, fees, term, and total payments alongside the monthly payment. Treat a simple payback calculation as a limited estimate: installation cost divided by estimated annual energy savings leaves out financing, repairs, future price changes, and the value of added cooling or comfort. If estimated annual savings are zero or negative, there is no positive energy-savings payback under those assumptions.
Use the installer-selection guide to discuss sizing, performance, scope, and service before signing.