HVAC System Cost Calculator & Price Guide

Installing an HVAC system typically costs $5,000 – $12,500, according to This Old House. HVAC stands for heating, ventilation, and air conditioning, so a full system can include a furnace or heat pump, an outdoor condenser, an indoor coil or air handler, a thermostat, and the ducts that carry air through the house. Which of those pieces you replace has the biggest effect on the bill.

Figures below come from published guides and carry a check date of Oct 11, 2026. Because sources define a "system" differently, each table shows what it measures. Cooling-only replacement is covered on the AC unit cost page, so this guide focuses on whole-system decisions.

The first table shows installed ranges by component. Furnaces have the widest spread, from basic gas models to high-efficiency units with variable-speed blowers. Air conditioners and heat pumps overlap, and a heat pump can replace both a furnace and an AC in milder climates.

A complete replacement means indoor and outdoor equipment are matched together. Matching components helps keep the system running as designed and usually keeps the manufacturer warranty intact.

Manufacturer sites give another reference point. Trane publishes installed replacement ranges that reflect its own product lines.

These ranges describe one brand, so treat them as a comparison point, since they are not a market average. Contractors may offer several brands at different price tiers.

A homeowner survey reported by This Old House gives average replacement costs for three system types.

A geothermal heat pump costs far more up front because it needs buried ground loops. A gas furnace and a ductless mini-split land in a similar average range, though they suit different homes. Mini-splits make sense where ducts are missing or poor. Furnaces fit homes with working ducts and a gas supply.

• Home size and layout. Bigger homes need more capacity and longer duct runs.
• Equipment type and efficiency. Variable-speed and multi-stage equipment cost more than single-stage units.
• Fuel source. Gas, electric, and heat pump systems have different equipment and installation needs.
• Ductwork condition. Reusing sound ducts saves money. Leaky, undersized, or missing ducts add to the job.
• Climate. Colder or hotter regions may call for larger or more specialized equipment.
• Access. Attic, crawl space, and basement installs vary in difficulty.
• Permits and code. Local rules affect both cost and timeline.
• Time of year. Demand peaks in the hottest and coldest months, and some contractors may charge more or book out further.

Several items fall outside the equipment price. Ask whether your quote includes them.

Ductwork and permits are the most common surprises. Duct changes can add noticeable cost, and permit fees vary widely by city and county.

Many contractors quote a flat job price, but hourly rates show how labor is priced for smaller work such as service calls.

The two rows come from different guides and describe slightly different work. One covers general HVAC contractor rates and the other covers labor on an AC install. Installation labor is typically folded into the total, so a flat quote does not always reveal the hourly rate behind it.

This Old House reports an average HVAC repair of $775. Actual repair cost depends on the part and the technician. A thermostat or capacitor repair is a short visit, while a failed compressor or heat exchanger is a much larger bill. Many companies charge a diagnostic or service fee that they may credit toward the repair if you proceed.

The two sources above overlap in their low and high ends, which suggests a reasonable planning range for a typical project. Differences come from what each guide counts. One may include only equipment and basic labor, another may include ductwork, permits, or higher-efficiency models. Region, home size, and brand mix can all shift a guide's numbers.

Repair is usually reasonable for a single failed part on a system that is still in good condition. Replacement deserves a serious look when repairs repeat, when the system is old, when it uses a refrigerant that is being phased out, or when comfort problems suggest it was never sized correctly. Ask the contractor for repair and replacement prices side by side, and for an honest view of the equipment's age and remaining life.

You can build a rough estimate without a calculator tool by following four steps.

1. Pick the system type you need: furnace, AC, heat pump, or a combined replacement.
2. Find the matching row in the tables above and note the low and high figures.
3. Add the extras that apply to you, such as ductwork, a permit, or a new thermostat.
4. Treat the total as a range and compare it with at least three written local quotes.

The result shows whether a bid is in line with published guides. A contractor's load calculation, which accounts for your home's insulation, windows, and layout, is still needed for sizing.

HVAC installation is not a typical DIY project. It involves gas lines, high-voltage wiring, refrigerant that requires federal certification to handle, and venting that must meet code. Mistakes can cause carbon monoxide hazards, fires, or equipment failure. Many warranties require a licensed installer. Hire a licensed contractor, ask for proof of insurance, and confirm that they will pull required permits.

• Is the quote for a full system or a single component?
• Did you perform a load calculation, and what size are you recommending?
• Does the price include ductwork, permits, a thermostat, and removal of old equipment?
• What brands, models, and efficiency ratings are quoted?
• What are the warranty terms on equipment and on labor?
• What is the installation timeline?