On average, replacing an AC and gas furnace system in a 2,100-square-foot home costs about $8,386 for a mid-range 14.3 SEER2 (Seasonal Energy Efficiency Ratio) system. Expect to pay between $5,720 for a basic 12.4 SEER2 unit and $14,883 for a premium 16.1 SEER2 unit. Your final cost depends on several factors, including the type of system you choose, its efficiency rating, and the complexity of the installation.
Understanding the HVAC options available and the replacement process is essential for making informed decisions. In this guide, we’ll walk you through what you can expect to pay, how system types and SEER2 ratings impact price, and installation costs.
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HVAC Replacement Costs by System Type
Choosing the right HVAC system is one of the most important decisions you’ll make for your home’s comfort and efficiency. There are five main system types to consider, such as AC and gas furnaces, AC and electric furnaces, heat pumps and air handlers, dual fuel systems, and air conditioner-only systems. You’ll also need to think about the SEER2 rating, which measures how efficiently a system cools your home over an entire season. Normally, the higher the SEER2 rating, the more efficient the system, and typically, the more it costs.
For a 2,100-square-foot home, here’s what you can expect to pay across different system types, based on low (12.4 SEER2), high (16.1 SEER2), and average (14.3 SEER2) price points:
| System Type | Low Cost | High Cost | Average Cost |
|---|---|---|---|
| AC & gas furnace | $5,720 | $14,883 | $8,386 |
| AC & electric furnace | $5,113 | $13,245 | $7,446 |
| Heat pump & air handler | $5,645 | $14,680 | $8,269 |
| Dual fuel system | $7,339 | $19,249 | $10,890 |
| Air conditioner only | $5,268 | $13,662 | $7,685 |
HVAC Replacement Cost Breakdown
When planning your HVAC replacement, it’s important to understand what you’re paying for. Costs aren’t just about the equipment—they also include labor and permits. Labor typically accounts for a big portion of the bill, covering installation, wiring, refrigerant handling, and testing. Permits, which ensure the system complies with local codes, typically cost a few hundred dollars.
Here’s a breakdown of these cost components based on a 14.3 SEER system:
| Cost Component | Estimated Cost |
|---|---|
| Equipment (unit) | $4,935–$8,933 |
| Labor | $1,299–$2,960 |
| Total | $6,234–$11,893 |
Understanding this breakdown helps you budget realistically and avoid surprise expenses.
Additional Charges for an HVAC Installation
Beyond the basics, some optional add-ons can improve comfort and efficiency. These include smart thermostats, zoning systems (which let you control temperatures in different parts of the house), and ductwork repairs or replacements. While these extras can increase your upfront cost, they often pay off in improved comfort and long-term energy savings.
| Additional Charge | Estimated Cost |
|---|---|
| Thermostat | $39–$217 |
| Ductwork Replacement | $1,500–$3,000 |
| Permits | $250–$400 |
How Do I Determine the Tonnage or SEER2 Rating?
Tonnage refers to your system’s cooling capacity, not its weight. One ton equals 12,000 British Thermal Units (BTUs) per hour. For a 2,100-square-foot home, you typically need a 3.5-ton system, depending on your home’s insulation, layout, and your local climate. SEER2 ratings reflect energy efficiency; the minimum rating today is 12.4 SEER2, but upgrading to 16.1 SEER2 can significantly reduce energy bills.
The table below summarizes the average, low, and high costs for an AC and gas furnace system in a 2,100-square-foot home, based on 12.4–16.1 SEER2 systems.
| SEER2 Rating and System Type | Low Cost | High Cost | Average Cost |
|---|---|---|---|
| 12.4 SEER2 (AC & gas furnace) | $5,720 | $10,962 | $7,673 |
| 13.4 SEER2 (AC & gas furnace) | $5,916 | $11,316 | $7,944 |
| 14.3 SEER2 (AC & gas furnace) | $6,234 | $11,893 | $8,386 |
| 15.2 SEER2 (AC & gas furnace) | $6,200 | $11,830 | $8,338 |
| 16.1 SEER2 (AC & gas furnace) | $7,887 | $14,883 | $10,676 |
Note that SEER2 requirements vary by region. For example, the Southeast and Southwest regions require a minimum of 14.3 SEER2 for new central air conditioners. Lower-rated units, such as those with a 12.4 SEER2, are no longer widely available due to updated federal efficiency standards. Your contractor can help you ensure your unit meets requirements.
How Does My Location Affect Cost?
Where you live can have a big impact on the total cost of a new HVAC system. Labor rates are generally higher in urban and coastal areas, and typically account for five hours per unit of installation time. In regions with challenging installation conditions, such as tight crawl spaces, expect to pay on the higher end of the labor range. The high end of labor costs typically comes from the Northeast and Hawaii, ranging as high as $2,960 for a 2,100-square-foot home. On the contrary, the South generally is the most affordable, with some areas having labor costs as low as $1,299.
Editor’s note: Although this article discusses SEER2 ratings in the context of AC and gas furnace split systems, SEER2 applies only to the air conditioning portion. SEER2 measures cooling efficiency and does not apply to the heating performance of gas furnaces.
FAQs About Air Conditioner Costs for a 2,100-Square-Foot Home
Should I replace my furnace at the same time as my air conditioner?
While you can replace just your air conditioner, there are several benefits to replacing both your furnace and AC simultaneously. First, matched systems from the same manufacturer are designed to work together efficiently, potentially improving performance and energy savings. Second, if your furnace is more than 15 years old, replacing both units at once saves you from paying for labor twice within a few years. However, if your furnace is less than 10 years old and in good working condition, you might consider replacing only the air conditioner for now.
How will the 2025 refrigerant regulations affect my new system?
Beginning January 1, 2025, manufacturers will no longer be able to produce residential HVAC equipment using R-410A refrigerant due to its pollution potential. New systems will instead use more environmentally friendly refrigerants, such as R-454B or R-32, which have a significantly lower environmental impact. While you can still use and service existing R-410A systems, choosing a system with the newer refrigerants is a more future-proof option if you’re installing a new unit now.
How do I compare contractor quotes for my 2,100-square-foot home?
When comparing HVAC contractor quotes for your 2,100-square-foot home, look beyond just the bottom-line price. First, ensure each quote specifies the same system size (tonnage) and efficiency rating (SEER2) to make an apples-to-apples comparison. Check what they include in each quote—some may bundle extras, such as programmable thermostats or air purifiers, while others price these separately.
Review warranty terms carefully, as coverage can vary significantly between contractors even for the same brand. Confirm that each quote includes necessary permits and that the contractor will handle this paperwork. Ask about their post-installation service policies and maintenance packages. Finally, verify that all contractors are properly licensed, insured, and have positive reviews or references from previous customers in your area.
Will a new high-efficiency system really save me money in the long run?
A high-efficiency HVAC system can indeed save you money over time, but the payback period depends on several factors. Upgrading from an old 10 SEER system to a new 15.2 SEER system could reduce your cooling costs by up to 38%, with yearly savings ranging from $200 to $500, depending on your climate and usage patterns.
How We Get Our HVAC Cost Data
Replacing an HVAC system is a large investment. Throughout this article, we estimated what it would cost to replace an HVAC system in a 2,100-square-foot home. Keep in mind: These are estimates intended to help you understand what a project like this might cost. You should get quotes from at least two companies to understand the true costs in your area.
We collected unit prices and the average cost of labor to calculate a total estimated price to replace an HVAC system in a 2,100-square-foot home. For unit costs, we collected wholesale prices for air condensers, electric furnaces, gas furnaces, evaporator coils, heat pumps, and air handlers from three sources, including: AC Direct, HVACDirect.com, and Buy Comfort Direct. We calculated prices for the total system using various combinations of unit costs. We also added an estimated retail markup. For labor, we researched the average time it takes to replace an HVAC system and multiplied this by the average cost of labor.