In summer, they are the same machine
A heat pump in cooling mode is a central air conditioner. Same compressor, same coils, same refrigerant cycle, same SEER2 rating scale. A 3-ton heat pump at 16 SEER2 cools a Memphis house the same way a 3-ton AC at 16 SEER2 does.
Bluffline Memphis Heat Pumps prices both on the same estimate when an AC fails, so you can see what the heat pump adds.
The one extra part
A heat pump has a reversing valve that flips the refrigerant’s direction, so the outdoor coil gathers heat in winter and the indoor coil releases it. It also has defrost controls for cold, damp mornings.
Side by side
The differences are all on the heating side:
| Central AC | Heat pump | |
|---|---|---|
| Cooling | Yes | Yes, identical at the same rating |
| Dehumidification | Yes | Yes, identical |
| Heating | No; needs a furnace or strips | Yes, two to four units of heat per unit of electricity |
| Runs in winter | No | Yes |
| Extra parts | None | Reversing valve, defrost controls |
| Price step at the same size | Base | Modestly higher |
| TVA rebate | Not part of the heat pump program | Qualifying heat pumps at 15 and 17 SEER2 |
What your house heats with now
The value of switching depends on what does the heating.
Strip heat or an electric furnace
The heat pump replaces the AC and becomes the main heat, with smaller strips as backup. On MLGW’s rates strip heat costs about $35.80 per million BTU and a heat pump about $10.20 to $14.30, so the winter bill drops sharply. This is the clearest case for switching. See electric furnace to heat pump.
A sound gas furnace
The heat pump replaces the AC and sits on the furnace as a dual fuel system. On MLGW’s typical rates gas is cheaper per BTU, so the heat pump earns its place through steadier mild-day heat and a second heat source. See dual fuel.
An old heat pump
You already have one. A heat pump replacement keeps it that way, sized for the house.
The price step
At the same size and efficiency, a heat pump outdoor unit costs modestly more than an AC. In a dual fuel setup the indoor coil is similar; in an all-electric setup the air handler is similar too.
What it buys
- A second heat source if the furnace fails in January.
- Mild-day heat that is steadier and quieter than a furnace’s short bursts.
- Flexibility when gas prices spike.
- The TVA rebate, on qualifying heat pumps for MLGW customers.
Bluffline’s typical range for an outdoor unit only is $4,500 to $9,000, and for a heat pump on a kept furnace $5,000 to $10,000. Your written estimate after the visit sets the price.
Running costs in summer
None. A heat pump and an AC at the same SEER2 use the same electricity to cool. If the heat pump has a higher rating than the AC it replaces, it uses less. SEER2 and HSPF2 explained covers the numbers.
Running costs in winter
It depends on what the heat pump replaces.
| Heat source | Cost per million BTU on MLGW |
|---|---|
| Electric strips | About $35.80 |
| Heat pump, cold day | About $14.30 |
| Heat pump, mild day | About $10.20 |
| Gas, 95 percent furnace | About $6.30 |
The gas versus heat pump guide explains why gas usually wins on MLGW and when it doesn’t.
What changes on install day
Swapping an AC for a heat pump is nearly the same job as swapping an AC for an AC. The differences:
Outside
The heat pump sits on the same kind of raised pad, but raised enough for defrost meltwater to drain away in winter, which an AC never needed. It may be a little larger than the old AC, so clearances get checked against the new unit’s dimensions.
Inside
- Dual fuel: a matched coil on the furnace, a dual fuel thermostat and an outdoor sensor.
- All-electric: a matched air handler with backup strips, and a heat pump thermostat.
At start-up
Besides the cooling checks, a heat pump gets heating checks: a forced defrost, backup heat staged and the strip lockout or gas switchover set with you. The commissioning checklist lists them.
Three Memphis houses
The same choice plays out differently in three typical houses:
| House | Heats with | What the heat pump changes |
|---|---|---|
| 1971 Millington ranch | Electric furnace, 15 kW strips | Winter heating cost falls by more than half |
| 1984 Germantown two-story | Eight-year-old gas furnace | Second heat source and mild-day comfort; summer the same |
| 2005 Arlington house | Gas furnace with a builder heat pump | Stays a heat pump; sized and placed better |
The Millington and Germantown pages show those jobs in detail.
Wear and lifespan
A heat pump runs in both seasons, so it logs more hours than an AC that rests all winter. In Memphis that can shorten its life somewhat compared with an AC in the same house. Good installation and care matter more than the difference.
The lifespan guide covers both.
When a plain AC still makes sense
A plain AC is still the right buy in a few cases:
- You only ever want gas heat and don’t value a second source.
- The furnace blower can’t carry a heat pump’s airflow, and you don’t want to replace the furnace.
- The budget is very tight and every dollar counts this year.
The rebate difference
On MLGW and other TVA power companies, TVA EnergyRight pays $500 for a qualifying heat pump at 15 SEER2 and $800 at 17 SEER2, installed by a participating contractor in TVA’s Quality Contractor Network. A plain AC isn’t part of that heat pump program.
That rebate can cover much of the price step from an AC to a heat pump of the same size. The TVA rebate guide has the rules.
Myths worth clearing up
“Heat pumps don’t work in the cold”
Older units struggled below freezing, and that reputation stuck. A correctly sized modern heat pump keeps heating well below Memphis’s 20-degree design temperature, with backup heat for the coldest hours. Cold-climate equipment isn’t needed here.
“Heat pump air feels cold”
In heating, a heat pump’s supply air is in the 90s, cooler than a furnace’s. It runs longer and more evenly, so the house holds temperature, but the air at the register feels milder. Most people adjust within a week.
“A heat pump costs much more than an AC”
At the same size and rating, the step is modest. The bigger price differences come from efficiency tier, variable speed, duct work and electrical changes, which apply to either.
“It will raise my summer bill”
Not at the same SEER2. In summer it is an AC, and if it carries a higher rating than the unit it replaces, the summer bill goes down rather than up.
The decision in short
In a strip-heat house, switch: it is the biggest bill change available. In a gas house with a sound furnace, a heat pump costs a little more than an AC and adds comfort, a backup and flexibility.
The Memphis buying guide puts the whole decision in order, and the cost page lists every range.