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What Temperature Should You Switch Off Your Heat Pump?

At EIA’s outlook prices a heat pump needs COP 3.73 to beat a 95% gas furnace; find the exact outdoor temperature where your furnace takes over.

Outdoor temp where furnace cost < heat pump costWhat it solves for
Named NEEP-listed cold-climate capacity/COP at 47/17/5°FHeat pump side
Your entered AFUE ratingFurnace side

· Source: EIA Electric Power Monthly Table 5.6.A (July 2026 data) · next EIA update ~Oct 23

On this page: CalculatorTableHow we calculatedSources

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What changes if…

Sliders scale the two prices to test sensitivity; the numeric fields stay the precise inputs. The URL keeps your scenario.

Crossover temperature: —
Heat pump at 47°F: —
Furnace: —

What it solves for
Outdoor temp where furnace cost < heat pump cost
Heat pump side
Named NEEP-listed cold-climate capacity/COP at 47/17/5°F
Furnace side
Your entered AFUE rating
Rate inputs
Your $/kWh and $/therm, or state EIA defaults (vintage shown)
Winter-month split
Mean monthly temp = 65°F − (HDD ÷ days in month)
What it ignores
Demand charges, tariff seasonality, multi-zone homes

Why this number

This tool finds the outdoor temperature below which running your gas furnace costs less per unit of heat delivered than running your heat pump — its economic balance point. It converts your $/kWh and $/therm (your own numbers, or your state’s newest EIA-published rates with the vintage shown) into a cost per BTU on each side: the furnace side divides by your AFUE, the heat pump side divides by the coefficient of performance (COP) of a named NEEP-listed cold-climate model at its rated 47°F/17°F/5°F test points, interpolated between them. Where those two costs cross is the crossover temperature; below it, backup or furnace heat is the cheaper choice even if the heat pump can still physically do the job. The page also splits your winter into months using regional degree-day data, estimating each month’s mean outdoor temperature as 65°F minus heating degree-days divided by days in the month, and shows which side of the crossover each month falls on.

A heat pump and a furnace deliver the same thing — heat — at costs that cross somewhere on the thermometer. This tool finds where, for your prices and a named, NEEP-listed machine.

The NEEP-listed units behind the picker

Named NEEP-listed cold-climate heat pumps with capacity and COP at 47, 17 and 5 degrees Fahrenheit
Brand / outdoor unitAHRITypeTons47°F COP / BTU17°F COP / BTU5°F COP / BTUListing
Mitsubishi Electric MUZ-GS24NAHZ***207679256ductless22.67 / 369002.22 / 254001.95 / 21200NEEP
Mitsubishi Electric PUZ-HA30NKA207702688ducted2.53.29 / 340002.11 / 320001.93 / 32000NEEP
Fujitsu AOU24RLXFWH8779046ductless23.14 / 362002.26 / 277002.03 / 23200NEEP
Daikin DZ6VSA361EA*212614865ducted33.42 / 342002.25 / 370002 / 30000NEEP
LG KUSXB301A214796354ducted2.52.71 / 370002.29 / 320002.02 / 30400NEEP
Bosch BMS500-AAS024-1CSXRC207760006ducted23.64 / 330002.41 / 226002.3 / 20000NEEP
Trane 4TXD2060A10NU**208141271ducted43.4 / 480002.04 / 480001.8 / 39000NEEP

Max-compressor-speed ratings at the NEEP mandatory test points, retrieved 2026-09-10 from the cold-climate ASHP database. Your installed system's real performance also depends on install quality, ductwork and controls.

A heat pump and a furnace deliver the same thing — heat — at different costs that depend on outdoor temperature. This tool finds the single outdoor temperature where the cheaper option flips, using your own rates, a named NEEP-listed cold-climate unit’s published performance, and your furnace’s AFUE.

How the crossover is calculated

Cost per unit of heat on the furnace side is your $/therm divided by AFUE (a therm is a fixed 100,000 BTU, so this converts price directly into cost per BTU delivered). Cost per unit of heat on the heat pump side is your $/kWh divided by COP, after converting kWh into BTU (1 kWh is a fixed 3,412 BTU) — and COP itself falls as outdoor temperature drops, which is why the tool interpolates between your chosen unit’s published 47°F, 17°F, and 5°F NEEP-listed points rather than using one fixed number. Setting the two costs equal and solving for outdoor temperature gives the crossover: above it, the heat pump is cheaper per unit of heat; below it, the furnace is. The winter-month split works the same logic forward — each month’s mean outdoor temperature is estimated from regional heating degree-days as 65°F minus HDD divided by days in the month, and compared against the crossover to show which months a typical winter favors which fuel.

Honest limits

This is single-zone math: one furnace, one heat pump, one house-wide balance point, not a room-by-room or multi-zone system model. It compares energy charges only — demand charges, minimum-bill provisions, and seasonal tariff pricing aren’t in the calculation, so check your own rate schedule for those before assuming the dollar gap is the whole story. And the monthly mean-temperature estimate is a regional average derived from degree-days, not a forecast or a record of your actual weather that winter — a mild or harsh month will move the real crossover date without moving the number this tool reports.

Next steps

If your system runs dual-fuel already, take the crossover temperature straight to the dual-fuel switchover calculator to set an actual thermostat changeover point. If a specific bill spike is what brought you here, why is my electric bill so high splits that increase into weather, rate, and usage. And for the degree-day mechanics behind the monthly split, see winter heating costs .


Frequently asked questions

What is a balance point, economically vs thermally?

They’re different questions. The thermal balance point is the outdoor temperature below which a heat pump’s rated capacity can no longer keep up with a house’s heat loss, so backup heat has to engage — a capacity question. The economic balance point, which this tool computes, is the outdoor temperature below which running the furnace costs less per unit of delivered heat than running the heat pump, even if the heat pump could still physically carry the load — a cost question. The two numbers can land at different temperatures for the same house.

Why does the answer change with my rates?

COP and AFUE convert fuel into delivered heat; your $/kWh and $/therm convert that heat into dollars. Raise the price of electricity relative to gas and the crossover temperature rises — the furnace becomes the cheaper option at a wider range of outdoor temperatures — and the reverse happens if gas gets relatively more expensive. That’s why this tool asks for your actual rates rather than a national average.

Are these named units representative of my heat pump?

The capacity and COP figures come from each model’s own NEEP cold-climate listing at the 47°F/17°F/5°F test points — published, manufacturer-submitted lab data, cited on the page. Your installed system’s real-world performance also depends on install quality, ductwork, altitude, and how closely your specific unit matches the listed model, so treat the named unit as the closest available reference point, not a guarantee of your own performance.

What about electric resistance backup heat?

Below a heat pump’s thermal balance point, or during defrost cycles, many systems bring on electric resistance strips, which cost far more per unit of heat than compressor-driven heat pump operation. This tool’s crossover math applies to normal compressor operation only — if your system’s controls lean on resistance backup more than expected, your actual winter bill will run higher than the crossover estimate implies, which is exactly the gap the dual-fuel switchover calculator is built to size.

How we calculated this

Furnace $/MMBtu = 10 × $/therm ÷ AFUE; heat pump $/MMBtu = 293.07 × $/kWh ÷ COP(T). COP(T) is interpolated between the chosen NEEP unit’s 47/17/5°F max-capacity COPs. Crossover = the temperature where they are equal, solved by inverting COP(T). Monthly mean temperature = 65°F − HDD/day from the EIA STEO division tables.

Sources: U.S. Energy Information Administration (EIA) electricity rates · DSIRE incentive records · public IRS/OBBBA guidance. Figures are modeled estimates, not quotes or tax advice. See our methodology.

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