Nobody wants to call for a quote before they have any idea what the number looks like. So here are real ranges, what moves them, and how to tell whether the quote in your hand is sane.
One caveat worth stating plainly: these are market ranges, not a price list. Two identical houses on the same street can land thousands apart depending on ductwork, electrical and access. Any calculator that gives you a firm number without seeing your attic is guessing, including the ones that look official.
The short answer
| What you are replacing | Typical installed range |
|---|---|
| AC only, reusing good ductwork | $5,000 – $11,000 |
| Full system (AC + furnace), existing ducts | $11,500 – $14,000 |
| Full system + new ductwork | $7,000 – $16,000 |
| High-efficiency or premium package | $9,500 – $20,000+ |
A useful sanity check: installed cost commonly works out to roughly $3 to $6 per square foot of conditioned space.
Cost by system size (tonnage)
Tonnage is capacity, not weight. One ton equals 12,000 BTU of cooling. Bigger is not better, and we will get to why.
| Size | Roughly suits | Typical installed cost |
|---|---|---|
| 2 – 2.5 ton | ~1,000 – 1,400 sq ft | under $6,000 |
| 3 – 3.5 ton | ~1,400 – 1,900 sq ft | $7,000 – $11,000 |
| 4 ton | ~1,900 – 2,400 sq ft | $11,000+ |
| 5 ton | ~2,400 – 3,000 sq ft | $13,000 – $17,000 |
Those square-footage figures are a starting point, not a rule. In the Sacramento valley, where systems fight 105-degree afternoons for months, the same house often needs different capacity than it would in a mild coastal town. Orientation, glass, insulation and shade all move it.
How much is a new AC unit for a 1,500 sq ft house?
This is the single most common version of the question, so let us answer it directly.
A 1,500 square foot home usually lands on a 3 to 3.5 ton system, which puts a straightforward AC replacement on existing ductwork in the $7,000 to $11,000 range installed. Replacing the furnace at the same time pushes it toward the low-to-mid five figures.
What would push a 1,500 sq ft house above that range: a west-facing wall of single-pane glass, an attic full of failing duct insulation, an electrical panel with no room, or a high-efficiency variable-speed system instead of a basic single-stage unit.
What actually drives your number
- Ductwork. The biggest swing factor by far. Sealing and repairing existing runs is far cheaper than replacing them, but old, leaking, poorly insulated duct in a 140-degree attic will eat the performance of whatever you buy. We check before quoting.
- Efficiency tier. Single-stage is cheapest. Two-stage and variable-speed cost more and are genuinely worth it in a long cooling season, though they will not rescue a badly ducted house.
- Refrigerant transition. New systems now use A2L refrigerants such as R-454B, which run roughly 5 to 10% more than the old R-410A equipment did. Your existing R-410A system remains legal to service and recharge, so nobody should be pressuring you to replace a working unit over this.
- Electrical. Mostly relevant when moving to a heat pump. Older panels frequently lack space for a dedicated 240-volt circuit, and an upgrade is a real line item.
- Access. A furnace in a tight 1920s closet, a rooftop unit needing a crane, a crawlspace you cannot stand in. Labor time is labor cost.
- Permits. Required for replacements, and California’s Title 24 can add duct sealing and testing depending on scope. Anyone skipping the permit is saving themselves time, not saving you money, and it surfaces when you sell.
Why the cheapest quote often costs the most
When three quotes come back thousands apart, the gap is rarely the equipment. It is what is excluded.
Look for whether the quote names the full matched system rather than just a brand and a tonnage. Ask whether a load calculation was performed or whether they matched the old nameplate. Check whether the permit, duct work, electrical and haul-away are in the price or waiting to be added later.
Roughly 80% of how long a system lasts comes down to installation quality. A mid-tier unit installed carefully outlives a premium unit installed in a hurry, which means the cheap quote with a great brand name on it is often the worst value on the table.
Should you repair instead?
Sometimes, and we will tell you when. The rough test: if the unit is past about 15 years and facing a repair over roughly a thousand dollars, put the money toward replacement. Under ten years with a common part failure, repair it. A cracked heat exchanger is not a budget decision at any age, it is a carbon monoxide issue.
Our repair diagnostic is a flat $69 and it goes toward the repair, so finding out costs very little.
Ways to bring the number down
Replace in spring or fall rather than during a July heat wave, when everyone is booked and you are deciding under pressure. Register the warranty immediately, since most require it within 60 to 90 days and an unregistered ten-year warranty quietly becomes a shorter one. Check rebates: SMUD has actively incentivized heat pumps, and qualifying high-efficiency equipment can earn a federal tax credit. And spend on duct sealing before spending on efficiency tiers, because it is cheaper and does more.
Getting a real number
An honest quote comes after someone has looked at your attic, your ducts, your panel and your house, and it should be itemized so you can see equipment, labor and extras separately.
That is how our installation and replacement quotes are written. If you are still choosing equipment, our guides to the best central air conditioner brands and the best HVAC brands cover what is actually worth paying for. We work across Sacramento, Roseville and the surrounding towns.
Frequently asked questions
How much does a new HVAC system cost?
Replacing a full system with existing ductwork typically runs about $11,500 to $14,000 installed. An AC-only replacement on good ducts is usually $5,000 to $11,000, while premium or high-efficiency packages can reach $20,000 or more. Installed cost commonly works out to roughly $3 to $6 per square foot.
How much is a new AC unit for a 1,500 sq ft house?
A 1,500 square foot home usually needs a 3 to 3.5 ton system, which puts a straightforward replacement on existing ductwork around $7,000 to $11,000 installed. Failing ductwork, difficult access or a jump to variable-speed equipment pushes it higher.
What does a 3 ton AC unit cost installed?
Expect roughly $7,000 to $11,000 installed for a 3 to 3.5 ton system on existing ductwork. Equipment alone is a fraction of that, which is why equipment-only prices found online rarely match real quotes.
Are online HVAC cost calculators accurate?
They are useful for a ballpark and nothing more. A calculator cannot see your ductwork, your electrical panel, your attic access or the orientation of your glass, and those are exactly the things that move the price by thousands.
Does a new system cost more because of the refrigerant change?
Somewhat. Equipment using the new A2L refrigerants such as R-454B runs roughly 5 to 10% more than comparable R-410A equipment did. Your existing R-410A system is still legal to service and recharge, so this is not a reason to replace a working unit.