Two outdoor units sitting side by side on the same gravel pad. Same brand family, same tonnage, same 10-year parts and labor warranty. One is a single-stage unit that costs a few thousand dollars less installed. The other is a variable-speed system the salesperson calls "the best tier."
That's the fork in the road on most heat pump estimates in Federal Way, Kent, Puyallup and Olympia. Here's how we explain the difference to homeowners standing in their own driveway, including the part where we tell some of them to buy the cheaper one.
What the compressor stage actually controls
A heat pump moves heat. How smoothly it moves heat is what these tiers describe.
- Single-stage. One speed: full blast or off. The thermostat calls, the compressor slams to 100%, the house overshoots slightly, the system shuts down, and it repeats. This is how most heat pumps built before the last decade worked, and it still works fine.
- Two-stage. A low setting and a high setting. It runs on low most of the year and kicks to high on the coldest mornings or the hottest August afternoons.
- Variable-speed (inverter-driven). The compressor modulates continuously, often anywhere from roughly 25% to 100% of capacity. Instead of sprinting and resting, it jogs all day at whatever output the house actually needs.
The efficiency ratings follow from that. A modulating system spends most of its hours at part load, and equipment is more efficient at part load than at full tilt, which is why variable-speed units post the higher SEER2 and HSPF2 numbers on the yellow sticker.
What the price difference looks like here
A ducted heat pump in standard Puget Sound markets runs $12,000 to $18,000 installed. In affluent markets like Seattle, Maple Valley, Normandy Park or Fircrest it's $13,800 to $21,600, and in luxury markets like Bellevue, Gig Harbor and Fox Island $15,000 to $24,300.
Those ranges aren't arbitrary. Broadly:
| Tier | Where it usually lands in the range |
|---|---|
| TierSingle-stage (Good) | Where it usually lands in the rangeBottom of the range |
| TierTwo-stage (Better) | Where it usually lands in the rangeMiddle |
| TierVariable-speed (Best) | Where it usually lands in the rangeTop of the range, or above it in premium markets |
Home size, ductwork condition, electrical work and site access move the number as much as the compressor tier does. That's why we present Good, Better and Best on every written proposal instead of quoting one figure. If you want the shape of your own number before anyone visits, the instant estimate tool gets you there in about a minute, and our full Washington heat pump cost guide breaks down every price driver.
What you actually feel with variable-speed
The brochure sells efficiency. The real-world payoff is comfort. Four things change:
1. Temperature swing gets smaller
A single-stage system typically lets the house drift a couple of degrees before it fires, then overshoots on the way back. Variable-speed holds much closer to setpoint because it never fully stops chasing it. In a house where somebody is always adjusting the thermostat, that's the difference people notice within a week.
2. It gets quieter
A modulating unit spends most of its life at low speed, and low speed is dramatically quieter than full speed. If the outdoor unit has to sit under a bedroom window, near a patio, or six feet off a neighbor's property line — common on Puget Sound infill lots and townhome sites — that's a real feature, not a luxury.
3. Humidity control improves
This matters more here than most contractors admit. A heat pump removes moisture as a byproduct of cooling, and long, slow runtime removes more total moisture than short bursts do. In the muggy stretch from July to September, a modulating system leaves the house feeling drier at the same thermostat setting.
4. Airflow evens out between rooms
Longer, gentler run cycles keep air moving through the whole duct system instead of blasting the nearest register and quitting. Two-story homes with a hot upstairs benefit the most — though if the upstairs return is badly undersized, no compressor tier fixes that.
Where single-stage is genuinely the right call
We install plenty of single-stage systems and don't apologize for it.
- Small, tight homes. A 1,200 sq ft rambler with decent insulation has a small load. Put a modulating system on it and the extra capability rarely gets used.
- Rentals and homes you'll sell in a few years. Buyers care that there is a heat pump. They don't shop compressor tiers.
- Budget is the deciding constraint. Getting a reliable, correctly sized heat pump installed at the bottom of the range beats stretching for a tier you can't comfortably pay for. The cheaper system still heats and cools the whole house and still carries the same 10-year parts and labor warranty.
- Ductwork needs the money more. If the ducts are leaky, undersized or falling apart in the crawl space, fixing them buys more comfort per dollar than upgrading the compressor. We'll say that out loud at the estimate.
Where variable-speed earns it
- Larger or multi-level homes, where a single-stage unit is oversized for most of the year and short-cycles through spring and fall.
- Homes with big temperature complaints already — one roasting room, one freezing room, constant thermostat fights.
- Noise-sensitive placements, including tight lots and bedroom-adjacent equipment.
- You're staying 10-plus years. Comfort you live with every day for a decade is worth more than a payback spreadsheet suggests.
- Colder pockets of the service area. Olympia's 17°F design temperature and the 19°F valley towns like Puyallup and Sumner ask more of the system than Tacoma's 29°F does. Modulation gives it more room to work.
The mistake that wastes the upgrade
Sizing. A variable-speed system installed two tons too large is still an oversized system — it just short-cycles more gracefully. Every Varsity estimate includes a real Manual J load calculation run against your city's actual winter design temperature, at no extra cost, because guessing off square footage is how homeowners end up paying premium-tier money for mediocre comfort.
Same goes for ducts. Low-speed airflow needs a clean path. If static pressure is high because the returns are choked, the system spends its life fighting the house.
What about rebates?
Rebate eligibility follows efficiency ratings and what you're converting from — not the words "variable-speed" on the invoice. Higher-tier equipment often clears qualifying thresholds more easily, but plenty of mid-tier systems qualify too. Programs change, so we confirm your current eligibility and handle the paperwork; our PSE rebate breakdown covers what's on the table now. Two things worth knowing: the federal 25C tax credit ended December 31, 2025, and starting April 2, 2026 PSE rebates require a PSE-certified installer. Varsity is PSE Certified.
One more caution: rebates follow the meter, not the county. PSE rebates apply to PSE customers. Tacoma Power, Seattle City Light, Peninsula Light and the Parkland-area mutual utilities run their own programs. We check which one bills your address before promising anything.
How to decide in one sitting
- Ask the contractor which compressor tier each price on the proposal represents. If the answer is vague, that's information.
- Ask what load calculation the sizing came from.
- Ask what the ducts measured, and whether duct work should come before an equipment upgrade.
- Then decide comfort-first: is your current complaint temperature swing and noise, or is it the thing is dead and it's February? Those point to different tiers.
Either way, the install is usually done in one day, permits pulled, warranties registered, rebate paperwork filed.
Want real numbers for your house? Request a free in-home estimate or call us at (253) 785-4622, Monday through Friday, 8 to 6. We'll show you Good, Better and Best side by side and tell you plainly which one your house is actually built for.