Heat pump vs furnace
See if a heat pump pays off against your oil, propane or gas heat. Enter your fuel use and prices and get the payback in years. Free, runs in your browser.
Replacing costs less by
$61 a year
$306 over 5 yearsExample calculationClose call
Replacing costs a little less. At these inputs, replacing costs about $61 a year less than repairing over 5 years ($306 in total). Replacing is the cheaper choice for any repair quote above $694; yours is $1,000. This is a close call: the gap is under 10 percent of the cheaper choice's total ($5,197).
- If fuel prices stayed flat the answer is the same: replacing costs about $52 a year less ($259 in total).
- Changes that give a different answer: a new system price 25% higher; a new system that lasts 15 years.
Repair, total over 5 years
$5,502
$1,100 a yearReplace, total over 5 years
$5,197
$1,039 a yearRepair limit
$694
Replacing wins above this quoteCash needed now
$1,000 or $6,000
Repair now, or the new system after rebatesSafety. If a technician says the heat exchanger is cracked or there is a carbon monoxide problem, tick the box in the first group: that is a safety problem, not a money question. Official pages: CPSC carbon monoxide questions and answers, EPA sources of combustion products, New York State DHSES safety tips and CDC carbon monoxide. A leaking oil tank is a separate problem from the boiler or furnace: see the New York DEC page on checking tanks and reporting leaks. This page gives no safety advice beyond these links.
Cost over the repaired system's life
Both choices are costed over the years the repair buys. The new system's price is spread over its own life, so only the part used in those years counts.
| Cost | Repair | Replace |
|---|---|---|
| Repair quote now | $1,000 | $0 |
| Another repair | none counted | $0 |
| Fuel or power over 5 years, with a 3% yearly rise | $4,502 | $3,697 |
| New system, share used (5 of 20 years of $6,000) | $0 | $1,500 |
| Total over 5 years | $5,502 | $5,197 |
| Per year | $1,100 | $1,039 |
| Cash needed now | $1,000 | $6,000 |
| Fuel or power a month, year 1 | $71 | $58 |
| Fuel or power a month, year 5 | $80 | $65 |
| Rating used | 78 percent | 95 percent |
| Total with fuel prices flat | $5,240 | $4,981 |
| Result in words | Replacing is $306 cheaper | |
Cost so far, year by year
The replace line stays below the repair line in every year.
The replace line starts at $0 because the new system's price is spread over its life, so each year counts a share of it.
Year-by-year table
| Year | Repair, cost so far | Replace, cost so far | Difference (repair minus replace) |
|---|---|---|---|
| Year 0 | $1,000 | $0 | $1,000 |
| Year 1 | $1,848 | $996 | $852 |
| Year 2 | $2,721 | $2,013 | $708 |
| Year 3 | $3,621 | $3,052 | $569 |
| Year 4 | $4,548 | $4,113 | $435 |
| Year 5 | $5,502 | $5,197 | $306 |
What changes the answer most
The new system's life changes the result most: 5 years more moves the difference $300 toward replacing and 5 years fewer moves it $500 toward repairing. The new system's price comes next.
| Change | Cheaper choice | Moves the difference |
|---|---|---|
| New system price 25% higher ($7,500) | Repairing, by $69 | $375 toward repairing |
| New system price 25% lower ($4,500) | Replacing, by $681 | $375 toward replacing |
| Repair quote 25% higher ($1,250) | Replacing, by $556 | $250 toward replacing |
| Repair quote 25% lower ($750) | Replacing, by $56 | $250 toward repairing |
| Fuel bill 25% higher | Replacing, by $507 | $201 toward replacing |
| Fuel bill 25% lower | Replacing, by $104 | $201 toward repairing |
| Repair lasts 7 years | Replacing, by $63 | $243 toward repairing |
| Repair lasts 3 years | Replacing, by $569 | $263 toward replacing |
| New system lasts 25 years | Replacing, by $606 | $300 toward replacing |
| New system lasts 15 years | Repairing, by $194 | $500 toward repairing |
| One more repair of $1,000 in year 3 | Replacing, by $1,306 | $1,000 toward replacing |
Rules of thumb, for comparison
- $5,000 rule (CBS News, 2026-06-24): age x quote = 15,000, which is above 5,000 and points to replacing.
- Half-price rule (DOE guide, 2011): the repair is 16.7% of the new system's price, which is less than half.
- Energy Star's age flag: your system is 15 years old, which is not over the 15 years it gives for furnaces and boilers.
These are shortcuts. They ignore fuel, efficiency and how long the repair lasts, which this page uses.
Good to know
Same fuel only. This page keeps the same fuel and kind of equipment. To compare switching to a heat pump, see Heat pump vs fossil fuel heating.
New York. Many New York homes burn heating oil. A 2017 review by an oil-heat trade group put replaced boilers at 33 years old and about 73% efficient (second-hand, from an interested party). This page does not know how old your boiler is, so type its rating.
Air conditioning. If your AC uses R-22 refrigerant and the repair is a refrigerant leak, ask what the refrigerant costs. EPA (updated 2026-04-01): no new R-22 has been made or imported since 2020-01-01, and existing systems may keep being used and serviced.
Credits. No federal credit applies to a 2026 purchase: it ended for property placed in service after 2025-12-31 (IRS, checked 2026-10-18). Type any utility or state rebate in More options.
Not counted. Ductwork, sizing, comfort, noise, warranty, maintenance, fan power, financing, tax, house value, equipment price changes and the time value of money.
How this estimates
The old unit's rating is the one you type, or the federal minimum for the year it was made (this year minus its age) if you leave it blank. For a central AC the old SEER times 0.95 stands in for SEER2, a rule of thumb and not an official conversion. The new system uses your yearly use times the old rating divided by the new rating, for the same heat or cooling. Fuel cost is that use times the price, and it rises by your yearly percent.
Both choices are costed over the years the repair buys. Repairing is the quote, any second repair you enter, and the old system's fuel. Replacing is the new system's fuel plus a share of its price after rebates: the price divided by its life, for each year used. Each total is added up year by year with the shared payback engine, with no discounting and no loan. The difference is repair minus replace, so a positive number means replacing costs less. The break-even repair quote is your quote minus the difference. The flat-price line repeats the sum with a 0% rise.
The result is "the same" when the totals match to the cent, "about the same" within 50 cents, and a close call when the gap is under 10 percent of the cheaper total. The biggest changes come from moving one input at a time: price, quote and fuel bill by 25%, the repair's years by 2, the new system's life by 5. The half-price rule is this model with equal ratings and a repair that lasts half the new life.
Not advice. An estimate from the numbers you typed. Not an offer, not financial, safety, tax or legal advice. Prices vary by home and region; check your quote.
Benchmark sources and dates
Starting assumptions are example benchmarks, not binding quotes. Change any input to match your own bills or offers.
| Assumption / Input | Starting value | Source | Checked |
|---|---|---|---|
| Repair quote | $1,000 (typical, edit this). Ranges: furnace $349 to $650, boiler $150 to $750, central AC $150 to $2,000 (second-hand) | Fixr repair guides, 2025-08-29 to 2026-01-29 (opened) | 2026-10-18 |
| New system, installed | $6,000 gas furnace, $6,500 oil furnace, $7,000 gas boiler, $7,500 oil boiler, $6,900 central AC (typical, edit this; second-hand; no New York price found) | Fixr guides, 2025-01-31 to 2026-01-28; HVACBase, 2026-10-15 (opened) | 2026-10-18 |
| Life of the new system | 20 years (18 for central AC), typical, edit this. DOE modeled averages: gas furnaces 21.5, boilers 24.6, central AC 21.2. Guides say 10 to 25 (second-hand) | DOE rules (opened; AC rule via govinfo.gov, federalregister.gov did not open: unverified); Fixr, CBS (second-hand) | 2026-10-18 |
| Years the repair lasts, a second repair, and the yearly price rise | 5 years; no second repair; 3% a year (all typical, edit this; the 3% is not a forecast) | None found (searched 2026-10-18) | 2026-10-18 |
| Old unit's rating (when left blank) | Blank: the federal minimum for the year made (78 to 86%; AC 10 to 14 SEER), a floor. Old SEER x 0.95 = SEER2 (rule of thumb; second-hand) | 10 CFR 430.32, eCFR 2026-10-01 (opened); HVACBase for 0.95 (opened) | 2026-10-18 |
| New unit's rating | 95% gas furnace, 87% oil furnace, 90% gas boiler, 87% oil boiler, 15.2 SEER2 AC (typical, edit this; Energy Star levels are in the hints) | Energy Star criteria (opened, undated) | 2026-10-18 |
| Yearly fuel or power use | 530 therms, 500 gallons or 2,800 kWh a year (typical, edit this; U.S. single-family averages) | EIA survey 2020, tables CE4.6 and CE4.7 (opened) | 2026-10-18 |
| Fuel and power prices | U.S.: gas $1.60 a therm, oil $6.04 a gallon, power $0.18 a kWh. New York: $1.78, $6.08, $0.25. Dates are in the hints | EIA, via the site's shared price files | 2026-10-08 |
| Rebates and credits | $0. The federal credit ended after 2025-12-31 (confirm). New York: unverified, NYSERDA pages returned 403 | IRS (opened); NYS Clean Heat (opened); NYSERDA not opened | 2026-10-18 |
| Rules of thumb (notes only, never the answer) | Notes only: $5,000 rule, half-price rule, Energy Star age flag (15 years, AC 10) | CBS News, DOE guide 2011, Energy Star (opened) | 2026-10-18 |
| Safety, oil tank and R-22 links | Links only, no advice of our own | CPSC, EPA, NY DHSES, CDC, NY DEC, EPA R-22 FAQ (opened) | 2026-10-18 |
| New York boilers: age and efficiency | 33 years, 73.19% (2017 trade average; second-hand, interested party). Not defaults | Oil and Energy, 2017 (opened) | 2026-10-18 |
| Pages that could not be opened | Unverified: NYSERDA (403), energy.gov Energy Saver (404), Energy Star landing pages (404), federalregister.gov (redirected) | Nothing from these is used | 2026-10-18 |