How should DC homeowners compare a heat pump with a furnace?

Compare them on what each costs you per unit of heat, whether your ducts and electrical service can carry a heat pump, and whether you want the gas bill gone. On illustrative DC rate components, a heat pump costs less to run once its seasonal COP passes about 2.4 against an 80% furnace, or 2.9 against a 95% one. At Perennial DC Heat Pumps we install ducted systems across Washington, DC, and we run that arithmetic on your own bills.

Is this about the furnace or about the gas?

Most homeowners are really making two decisions at once: what heats the house, and whether the gas account stays open. A furnace burns gas and blows the heat through your ducts; its efficiency, AFUE, is the share of fuel energy that reaches the house, commonly about 80% for older non-condensing units and above 90% for condensing ones. A heat pump moves outdoor heat indoors with electricity, delivers more heat than it uses, and reverses in summer to cool.

If your house is heated by radiators, it is a different project, because a ducted heat pump needs ducts. Our conversion service covers the forced-air scope, and the ducted-versus-ductless guide explains why we work only with ducted systems.

Will a heat pump keep up on the coldest nights?

That depends on its output at the cold end, so that is where we check it. A furnace puts out the same heat at 40°F as at 10°F. A heat pump’s output drops as the outdoor air gets colder, so we compare its output at ENERGY STAR’s 14°F heating design temperature for DC with your home’s calculated heat loss. We don’t size from your old furnace’s input rating, because many furnaces were oversized when they went in.

The air feels different, too. A furnace blows air well above body temperature in short bursts; a heat pump blows cooler air for longer. Neither feel means something is wrong. Our cold-climate page and sizing guide show how we run the capacity check at 14°F.

Backup changes the economics. Resistance strips turn each kWh into 3,412 Btu, a COP of 1, so an hour on strips costs far more per unit of heat than an hour on the compressor. In a dual-fuel system the backup is your furnace burning gas instead. That is why our estimate spells out the heating sequence, not just the equipment name.

Going all-electric or keeping the gas furnace as backup

If you want the furnace gone, an all-electric conversion removes it. With an ENERGY STAR ducted heat pump replacing gas heat, the current DCSEU tier is $4,000, or $5,000 for ENERGY STAR Most Efficient, paid after installation as a reimbursement. The application needs proof the fuel system was removed.

If your furnace is fairly new, a dual-fuel system keeps it and switches over below a set outdoor temperature. That can make sense when the ducts were sized for the furnace and it has years left. Plan on a retained furnace not qualifying for the conversion tier; our rebate guide lists the full conditions.

What will it actually cost to run each one?

Here is the illustrative arithmetic we use, on the DC Office of the People’s Counsel calculator components before riders and taxes. Gas commodity, distribution and PROJECTpipes add up to about $1.49 per therm, and one therm is about 29.3 kWh of energy. At 80% AFUE, a kWh of delivered heat from gas costs about 6.4 cents; at 95%, about 5.4 cents. Pepco’s per-kWh components come to about 15.4 cents above the usage thresholds.

Dividing 15.4 by 6.4 gives an illustrative break-even COP of about 2.4; dividing by 5.4 gives about 2.9. Above that seasonal COP, heat from the heat pump costs you less than heat from the furnace on these components. Your own bills, riders and taxes move the result, and our running-cost guide shows how to redo it with your usage. The installed price is a separate question: our typical range for a whole-home ducted system is $8,000 to $18,000 before rebates, and the cost guide explains what moves it.

Can your ducts and electrical panel handle it?

Ducts sized for a furnace can be too small for a heat pump, which usually moves more air for the same heat. A return that was fine for the furnace can choke a heat pump and cut its capacity, so we check it on the site visit. Our ductwork page covers what we look at.

Electricity is the other gate. A furnace runs on a small 120-volt circuit; a heat pump needs 240-volt circuits for the outdoor unit and air handler, and backup strips can add a large load. We run a load calculation to see whether your service has room. If you are planning insulation work, tell us, because it lowers the heat loss the heat pump has to meet at 14°F.

So which one is right for your house?

There is no universal winner, so we start with what you want: no more gas, a failing furnace or AC replaced, one problem room fixed, or the least disruption. A furnace near the end of its life alongside an aging air conditioner points to a full heat pump conversion; a five-year-old furnace with a dead AC makes dual fuel worth pricing.

If you are comparing proposals, our quote checklist helps line them up. Use the assessment tool to record your current system, then request an estimate with a year of Pepco and Washington Gas bills so we can run the break-even with your own rates.