16 Questions to Ask Before You Buy a New HVAC System

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Being careful is smart, especially with big buys. After all, getting a new HVAC system is a great deal for your home. It can shift your energy bills, the air quality, and even your home’s value. You might be tempted by the first affordable option. But there’s more to it than price. To pick the right one for you and your family, here are some key questions to ask before buying a new HVAC system.

1. Which Type of HVAC System is Right for Me?

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It might sound basic, but many people overlook this question. HVAC systems vary, and your options include:

If you’ve already got an HVAC system, it’s usually best to stick with the same kind. It simplifies installation and might even save you some cash. But if you’re starting fresh, here’s a quick rundown to guide your decision:

  • Central Air Conditioners: These are popular choices for cooling your entire home. Paired with a furnace, they’re great for those colder climates.
  • Heat Pumps: Want to save on energy and lessen your environmental impact? Heat pumps both heat and cool by moving heat around, making them an efficient pick.
  • Ductless Mini-Split Systems: If your home is older or lacks ducts, this system might be your match. With an outdoor unit connecting to individual indoor ones, you get tailored temperature control without the ductwork costs.
  • Hybrid Heating Systems: These switch between gas and electricity based on the outside temperature. While they offer energy efficiency and flexibility, they can cost more upfront.

Remember, these are just pointers. For advice tailored to your home and needs, it’s always best to ask this question to a trusted HVAC professional. They’ll help ensure you make the right choice for you and your family.

2. Which Energy Efficiency Rating is Ideal for Me?

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This isn’t just a question of eco-friendliness, though that’s important too. A system’s energy efficiency can greatly impact your monthly bills. Here are the minimal energy efficiency ratings to aim for:

  • Central air conditioners: 14 SEER;
  • Heat pumps: 14 SEER 8.2 HSPF;
  • Furnaces: at least 85% Annual Fuel Utilization Efficiency (AFUE);
  • Boilers: at least 82% AFUE.

SEER (seasonal energy efficiency ratio) gauges cooling and HSPF (heating seasonal performance factor) rates heating. A higher number means more efficiency. AFUE shows how much fuel a furnace or boiler turns into warmth. For example, 80% AFUE means 80% of the fuel becomes heat.

Remember to think about your local weather and your budget. The higher the efficiency rating, the more savings in the long run. But upfront costs can also be steep, so it’s about finding a balance that works for you.

And here’s a pro tip: ENERGY STAR-certified HVAC systems can cut your heating and cooling bills by up to 20%. Plus, you might get tax credits or rebates if you go green.

3. How Do I Choose the Right Size and Capacity?

You might be thinking, “I’m just looking for a new HVAC system, not trying to become an engineer!” But knowing these things matters. Get a system too small, and it won’t adequately heat or cool your home. Overshoot with a system too large, and you’re wasting money and energy. So, how do you find the sweet spot?

  • Assess your home’s size: Measure the total square footage of the areas you want to heat or cool. Not every room needs the same attention. Perhaps you have rooms you rarely use, or there might be areas that are naturally cooler or warmer.
  • Look at insulation: Homes with good insulation can make do with smaller systems since they retain heat or cold more effectively.
  • Check window locations and types: The amount, size, and direction your windows face can affect how much heat enters and leaves your space. North-facing windows, for instance, may not get much sunlight, while west-facing ones can make rooms really warm in the afternoon.

In the HVAC world, BTU (British Thermal Units)  and tonnage units help gauge a system’s size. Basically, they measure how fast a system can change the room’s temperature. A rule of thumb is to aim for 25 to 30 BTUs per square foot. 

So, if you have a 2,000 square foot area to cool or heat, then you need a system with at least 50,000 BTUs of output capacity. Regarding tonnage, one ton of refrigeration equals about 12,000 BTUs per hour. 

However, a manual J load calculation conducted by an HVAC contractor will give you the most accurate sizing for your specific home.


J load calculation estimates how much heat enters and leaves your home. It’s based on factors like the area, number of occupants, window size and types, insulation levels, and local weather.

4. What Kind of Ductwork Do I Need?

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Ductwork might not be the most glamorous part of an HVAC system, but it’s a vital component. Poor duct design or maintenance can lead to energy losses, uneven heating or cooling, and even compromised air quality. So, let’s dive into some considerations:

  • Existing vs. New Ductwork: If you’re replacing an old HVAC system and your home already has ducts, you might be in luck. But they should be inspected. Aging or damaged ducts can reduce your system’s efficiency.
  • Material Choice: Ducts come in different materials like galvanized steel, aluminum, and flexible ducting. The best choice often depends on your home’s layout and the HVAC system’s requirements.
  • Size: Duct size is vital. Too small or large ducts can impact efficiency.
  • Sealing and Insulation: Make sure your ducts are sealed and insulated. This helps air flow where it’s supposed to.

5. How User-Friendly is the System’s Thermostat and Controls?

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Ease of use is essential when it comes to managing your HVAC system efficiently. A complicated interface can lead to inefficiencies, while a user-friendly one can help conserve energy.

  • Does the system come with a smart or programmable thermostat?
  • Can you control the thermostat remotely, perhaps from a smartphone or tablet?
  • Does the thermostat offer energy usage reports to help you optimize consumption?
  • Is there a learning feature that adapts to your routine?

An intuitive thermostat that offers advanced features can make a significant difference in user experience, energy conservation, and cost savings. Ensure you’re comfortable with the system’s controls and that they meet your needs.

6. Can the System Improve Air Quality?

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Air quality is crucial for health and comfort. Poor indoor air quality can lead to respiratory problems, allergies, and other health issues. When choosing an HVAC system, consider how it might impact and even improve the air inside your home:


Check if the system has built-in air filters and what type they are. High-efficiency particulate air (HEPA) filters, for example, can capture at least 99.97% of particles 0.3 microns in diameter (like pollen and dust mites).

Humidity Control

Balancing humidity can enhance comfort and health. The cooling system usually reduces humidity levels in the air automatically. But in extreme climates, you might need a separate dehumidifier or humidifier.


A system that brings in fresh outdoor air and expels stale indoor air can improve air quality. Look for systems with good ventilation capabilities, especially if anyone in your family has respiratory issues.

UV Lights

Ultraviolet (UV) lights can kill microorganisms like bacteria and mold, improving air quality. They can be installed in HVAC systems to treat air passing through the ducts. While not a replacement for regular cleaning and maintenance, they can be a beneficial addition.

Air Purifiers

Air purifiers can further improve indoor air quality. They help trap air pollutants like smoke, odors, and volatile organic compounds (VOCs), potentially reducing the risk of health problems.

7. What Other Specialized Features Does the System Offer?

Technology has made HVAC systems smarter and more convenient. Now, you can control temperatures from afar with smart thermostats or enjoy custom airflow with special vents. Think about which cool features would make life better for your family. 

Some other specialized features HVAC systems may offer include:

  • Zoned Heating and Cooling: Divide your home into different zones, each with its own temperature setting. This means you can heat or cool specific rooms or areas according to their use, potentially saving energy and money.
  • Energy Efficiency Modes: Modern HVAC systems come with energy-saving modes that adjust the system’s performance to save on utility bills while maintaining comfort.
  • Voice Commands: Integrated with smart home systems like Alexa or Google Assistant, you can now command your HVAC system using just your voice.
  • Self-Diagnostics: Advanced HVAC systems can run self-diagnostics to identify any issues or malfunctions, making maintenance easier and potentially reducing repair costs.

8. What’s Covered in the Warranty? 

When you’re investing in an HVAC system, the last thing you want is unexpected repair costs. That’s where the warranty comes in handy. A warranty safeguards you against manufacturing defects and might save you significant repair costs. But warranties vary, and you must know the specifics, including:

  • Duration: How long is the warranty valid? Some last about five years, while others could span a decade. Make sure to register your system to get the full warranty benefits. 
  • Coverage: Not all parts of the HVAC system might be covered equally. For instance, the compressor might have a different coverage duration than the fans or the thermostats.
  • Registration: Some warranties require online registration or specific maintenance schedules. If you skip these, you could void the warranty.
  • Transferability: If you’re planning to sell your home, it’s worth knowing if the warranty can be transferred to the new owner. It might be a selling point!
  • Limitations: Most warranties have specific exclusions. They might not cover labor costs, or there could be exclusions for damages caused by external factors, like natural disasters.

To ensure you’re getting the best out of your warranty, always read the fine print and clarify any doubts with the manufacturer or your HVAC technician.

9. What Maintenance Does the System Require?

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Every HVAC system requires regular maintenance to ensure it runs efficiently and lasts a long time. Neglecting this can lead to decreased performance and a shorter lifespan for your system. It’s vital to understand the kind of attention your new system will demand, including:

  • Changing air filters regularly;
  • Scheduling annual maintenance checks;
  • Cleaning coils and vents;
  • Checking for leaks and other potential issues.

Ask the manufacturer or your HVAC contractor about specific maintenance requirements for the system you’re considering. Knowing what’s needed beforehand can help you plan and budget for maintenance costs. Plus, some HVAC companies offer maintenance plans to make the process more convenient for homeowners.

10. How Loud Will Your HVAC Be?

Sound can be a concern for many homeowners. No one wants to be kept awake by a noisy HVAC system or struggle to hear the TV over the hum of an air conditioner. Check the system’s decibel ratings to know its noise level. For reference:

  • A whisper is about 30 dB.
  • A chat is around 60 dB.
  • A busy road can be up to 80 dB.

You’d want your HVAC system’s noise to be somewhere between a whisper and a busy street. Mini-split systems are usually the quietest at around 30 dB. Central air systems can be louder, making noises between 50 and 80 dB.

Pro tips:

  • Placement can affect noise levels. Consider installing the unit away from the main living areas or bedrooms.
  • Look for vibration dampeners and advanced design features to reduce sound.
  • Proper insulation around indoor and outdoor components can also help dampen noise.

11. What Are the Installation Costs and Time? 

The purchase price of the HVAC system is just one part of the overall cost. Depending on the complexity, installation can sometimes be as much or even more than the system itself. Before you commit, get a clear understanding of:

  • Labor costs;
  • Any additional materials needed;
  • Duration of the installation;
  • Any potential disruptions to your daily life or property.

Having a clear timeframe and understanding of the entire installation process can help you plan and avoid any unexpected surprises.

The national average HVAC installation cost is $5,000 to $9,000 in total. However, the price can vary based on location and other factors. Get at least three quotes from reputable HVAC contractors in your area for accurate estimates.

12. Are There Any Incentives or Rebates Available?

Many local or federal government programs offer incentives or rebates for energy-efficient appliances, including HVAC systems. Before purchasing:

  • Research your local area’s programs.
  • Visit Energy.gov to learn about federal tax credits, rebates, and other incentives. Energy Star-rated HVAC systems may qualify for these benefits.
  • Ask your HVAC contractor for suggestions if you’re considering energy-efficient options to maximize savings.

13. What Brands or Models Are Reliable and Available?

With so many options out there, choosing the right HVAC brand or model can be overwhelming. You might come across reviews and advice from friends and family, but it’s always best to do your own research. Some factors to consider include:

  • Brand reputation and reliability;
  • Warranty terms;
  • Overall customer satisfaction ratings;
  • The availability of parts and technical support in your area.

A trusted HVAC professional can also provide recommendations based on experience and knowledge of the industry. Don’t be afraid to ask for their opinion on which brands or models they have seen perform well and last long.

14. What Type of Energy Source is Best for Me?

The energy source your HVAC system utilizes can greatly impact its efficiency, cost, and eco-friendliness. Depending on your region and the availability of different energy sources, you might have to decide between:

  • Electricity;
  • Gas;
  • Oil;
  • Propane;
  • Geothermal.

Electricity is generally more expensive than gas or oil, but it’s a greener option. Gas and oil, on the other hand, are more common options for heating systems. If you have access to natural gas, it’s often a more cost-effective and efficient choice. 

However, if your home doesn’t have access to gas lines or you want to be more environmentally friendly, you could consider a geothermal system. These systems harness the earth’s natural temperature to heat and cool your home, making them highly efficient and eco-friendly.

15. How Long Can I Expect the System to Last? 

Understanding the longevity of your investment is crucial. Different HVAC systems have varying lifespans, influenced by their design, quality, maintenance, and usage. Here are some general guidelines:

  • Central Air Conditioners: 15 to 20 years
  • Heat Pumps: 10 to 30 years (depending on the type)
  • Furnaces: 20 to 30 years (depending on the type)
  • Boilers: 15 to 20 years

Remember that while the system itself might last a certain number of years, individual components might need replacement sooner. Regular maintenance can extend the lifespan of your HVAC system and keep it running efficiently. Always inquire about the expected lifespan of the system you’re considering and any guarantees or warranties that might accompany it.

16. What Are the Basic Credentials of the HVAC Company?

Working with a reputable and experienced HVAC company for your new system installation is essential. Before hiring them, be sure to ask for their basic credentials like:

  • Licensing and certifications;
  • Insurance coverage;
  • Overall experience with HVAC-related work.

You can also use this opportunity to inquire about their scheduling and payment options, any manufacturers’ warranties they offer, and the paperwork required for the installation process. This will help you ensure that you are working with a reliable and qualified company for your HVAC needs.

FAQ About New HVAC Systems

What to look for when replacing an HVAC system?

First and foremost, it’s essential to evaluate your current system and its limitations. Usually, it is best to replace it with a similar one, but if your needs or budget have changed, you might consider alternatives. Other essential factors to consider include:

  • Your home’s size and layout;
  • Local climate;
  • Energy efficiency ratings;
  • Warranty and maintenance requirements.

What are the most common HVAC replacement mistakes?

Replacing your HVAC system is a significant investment, and making mistakes can be costly. Some common pitfalls to avoid include:

  • Not having your home’s size and layout assessed before choosing a new system;
  • Purchasing the cheapest option without considering long-term efficiency and maintenance costs;
  • Not verifying warranty coverage and requirements; 

Who should I call when my HVAC system isn’t working?

Once you’ve tried some basic troubleshooting steps, such as checking power sources and filters, it’s best to call an HVAC professional to diagnose and fix the issue. Attempting repairs on your own can be dangerous and may cause more damage. A service call to a technician will cost an average of $60 to $150 per hour.

Make an Informed Decision

Investing in a new HVAC system is a significant commitment, both financially and in terms of the comfort and health of your household. So, ask the right questions and do a bit of homework. This way, you’ll pick the best system for you while avoiding unexpected costs and setbacks in the long run. 

And remember, a local HVAC professional can answer all of these questions and guide you to make an informed decision. Don’t hesitate to reach out for their expertise when it comes to choosing the perfect type of system for your home.

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Luminita Toma

Luminita Toma is a nature-loving writer who simply adores anything pretty, from colorful flower gardens to chic interior design. After plenty of research on landscaping and home improvement, she’s got a keen eye for what makes a home beautiful. When she’s not sharing what she’s learned, there’s nothing she enjoys more than chilling with her friends, hitting the theatre, or traveling.