HVAC Repair and Replacement Guide

The common parts of an HVAC system include thermostat for temperature control, AC unit (central AC, furnace, or heat pump), duct work, compressor, evaporator coil, and exhaust outlets. We discuss them briefly below:

• Thermostat: This is the most interactive part of the entire HVAC system. It controls the heating and cooling devices by switching them on or off, or by regulating the airflow to maintain the desired temperature.


• Central Air Conditioners: Air conditioners distribute cool air throughout your home using a circuit or series of connected ducts. Central air conditioner is most common in warmer climate regions.


• Furnace: There are various types of furnaces, with the most common using gas combustion or electric resistance heat strips to produce the necessary heat. Since furnace installation can only produce heat, it is sometimes retrofitted with a central air conditioner to provide cool air during the summer months.


• Heat Pump: A heat pump is a variation of a central air conditioner. Heat pumps are capable of delivering both heated and cooled air. They work by transferring the inside heat outside during the summer months to cool the home and extracting heat from outside air or ground inside during the winter months. Heat pump systems are one of the most energy-efficient systems available today.


• Air Return: Air return is the starting point of your ventilation. Its main purpose is to suck the air along with its pollutants and contaminants from the environment through filters to be cooled or heated. This also helps to maintain air quality and airflow.


• Exhaust Outlets: Exhaust outlets are used to remove heat and gas from the environment, which can be done through chimney flue or vent stack.


• Ducts: Air ducts help to distribute heated and cooled airflow to maintain acceptable indoor quality of air. 


• Compressor: An air compressor part of the outside AC unit that helps to turn the warm refrigerant gas into liquid. It is in this compressor the heat is removed from the gas with the help of pressure.


• Evaporator Coil: Inside an AC unit, evaporator coils help cool down the air being circulated using a liquid refrigerant. A blower assembly — fan and motor — provides the necessary circulation to distribute the conditioned air.

The square footage area of your home is the top factor to determine the size of HVAC unit needed for your home. The size is calculated in tons based on how many BTUs you need to cool/heat your home. For example, for a 2000 sq. ft. home, you will need an AC unit size of 40,000 BTUs, or approximately 3.5 tons.

To find the ideal size for your home, consider these factors:

• Square Footage: This is a general guideline, not the only factor.


• Climate: Hotter climates need a larger capacity than mild ones.


• Insulation: Well-insulated homes require less BTU (British Thermal Units) for heating and cooling.


• Sun Exposure: South-facing windows let in more heat, requiring a larger system.


• Ductwork: Leaky or poorly designed ducts can reduce efficiency.

Use our AC size calculator to estimate the BTU requirements based on square footage. The calculators use a range of 20 BTU per square foot as a rule of thumb.

The following chart is an estimation for tonnage coverage based on the square footage of your property to show standard AC sizes available in the market.

Tons Needed For Room Size

Room Size	Tonnage Your Air Conditioner Needs
600 to 1100 square feet	1.5 tons
901 to 1400 square feet	2 tons
1201 to 1650 square feet	2.5 tons
1501 to 2100 square feet	3 tons
1801-2300 square feet	3.5 tons
2101 to 2700 square feet	4 tons
2401 to 3300 square feet	5 tons

By changing or upgrading your air filters to high-efficiency filters like a MERV 13 or 14, you can improve the air quality of your house. While standard filters can only capture larger dust particles, upgrading can significantly improve particle removal, including allergens like pollen and pet dander.

Some HVAC systems allow for additional filtration options like HEPA filters or UV germicidal lights. HEPA filters capture even tinier particles down to 0.3 microns, while UV lights help kill bacteria, mold, and viruses within the system.

The best HVAC system for your home will depend on a number of factors, including the size of your home, the climate in your area, and your budget. Here are some things to consider when choosing an HVAC system:

• The Size of Your Home: You will need an HVAC system that is sized correctly for your home. A system that is too small will not be able to adequately heat or cool your home, while a system that is too large will be less efficient.


• The Climate in Your Area: If you live in a cold climate, you will need an HVAC system that is good at heating. If you live in a warm climate, you will need an HVAC system that is good at cooling.


• Your Budget: HVAC systems can range in price from a few thousand dollars to tens of thousands of dollars. It is important to choose a system that fits your budget.

A ductless HVAC system, or mini split unit is beneficial for some homes based on certain needs for your household. A ductless system has multiple indoor units located in each room that you would like to have controlled heating and cooling. The mini split units are mounted on your home’s walls and connect to a compressor located outside of the home. Mini split units are easier to install than a central AC system but usually cost more upfront.

Some reasons you may be interested in a duct free AC unit would include:

• You want to cool or heat only one particular room, such as a garage or a new room that was added to the house.


• You do not use all of the rooms in your home and you would like to be energy efficient with your air conditioning use for only rooms you utilize.


• You prefer independent control of room temperature across multiple areas of your home.

Pros and Cons of Ductless AC – Mini Split System

Pro: They have lower energy costs than most of the split systems, and it is your best high-energy efficiency option. The biggest pro is that you don’t have to worry about ducts because they are ductless, so no extra infrastructure is needed.

Con: These systems are low heat effective, so if you live in cold climatic areas, getting an effective mini split system will be impractical and costly as mini split systems are costlier than traditional ones. Also, maintenance can be expensive in some areas as it is hard to get parts for the system. Consult with your HVAC contractor to know which would be the best option for you.

The most common type of HVAC system is the heating & cooling split system. Split HVAC units have two main systems, one dedicated to cooling your home and one dedicated to heating your home. They usually contain one indoor unit such as a furnace (found in a garage, utility closet, crawl space, garage, attic, or basement) and one outdoor unit such as a central air conditioner often located outside on a flat cement foundation called an AC pad.

The split systems can be configured in different ways according to the needs,

AC and Furnace: These systems are very popular and are also called forced air systems because they use blower fans in the furnace to circulate the air through ducts. They absorb untreated air and push treated air into the environment.

Heat Pump and Air Handler: Heat pump split systems are usually ideal for warm climate regions which do not experience freezing temperatures. The heat pump does not generate heat (instead absorbs ambient heat), so it is energy efficient. So the absorbed heat is circulated through the air handler via ducts. The heat pump’s function is reserved to distribute cold air in mild warm climates.

Pros and Cons of Split System

Pro: They are quite popular, efficient, and cost-effective HVAC systems. It is easy to replace the existing duct system without doing minor or no modifications. They are highly energy efficient in areas that require less heating or cooling.

Con: The forced air system may disperse dust and allergens around your home, and it might also disperse your kitchen odor to the parts of your home. The system also requires ductwork, which may be expensive for homeowners.

An air conditioner is designed solely for cooling by removing heat from the indoor air and expelling it outside. It’s best suited for hot climates and must be paired with a separate heating system, like a furnace, for colder weather. Air conditioners are ideal when cooling is the primary need, and they operate efficiently in warm environments. See how central air conditioners work.

A heat pump, on the other hand, can both cool and heat a home by reversing its operation to extract heat from the outside air and transfer it indoors. This makes it versatile and efficient in moderate climates, though its efficiency can drop in extremely cold weather. Modern heat pumps, especially cold-climate models, are better suited to handle lower temperatures compared to traditional heat pumps. See how heat pumps work.

Some of the best air conditioning brands to consider are Carrier, Trane, Lennox, American Standard, and Rheem. These brands are known for their reliability, efficiency, and performance across different models and price ranges.

Use our guide to top 10 best air conditioner brands where we compare brands based on cost of installation, AC unit efficiency, features, performance, warranties and customer satisfaction.

When replacing your HVAC system, you don’t necessarily have to choose the same type you currently have. There are often more energy efficient options available that could better suit your needs and climate. For example, if you have a traditional air conditioner and furnace, you might consider switching to a heat pump, which provides both heating and cooling and can be more efficient, especially in moderate climates. Ductless mini-split systems are another energy-efficient alternative, offering zoned heating and cooling with reduced energy loss compared to ducted systems.

Newer systems with higher SEER and HSPF ratings offer greater efficiency and can lower your utility bills over time. Additionally, advancements like variable-speed compressors and smart thermostat compatibility can further enhance efficiency and comfort. To determine the best option, consider factors like your local climate, existing ductwork, and energy goals. Consulting with a qualified HVAC contractor for an energy audit can provide insights into the most efficient systems for your home.

The average lifespan of an HVAC system typically ranges from 15 to 20 years for furnaces and 10 to 15 years for air conditioners and heat pumps, depending on the type, brand, and level of maintenance. Regular maintenance, such as changing filters and scheduling annual tune-ups, can help extend the system’s life. Here is a HVAC maintenance checklist that can help increase the lifespan and repairing bills.

Signs that it may be time to replace your HVAC system include:

1. High energy bills: If your energy bills have increased significantly, it could be a sign that your system is inefficient.  


2. Frequent repairs: If you are constantly dealing with repairs, it might be more cost-effective to replace the system.  


3. Uneven heating or cooling: Hot or cold spots in your home can indicate a problem with your HVAC system.  


4. Strange noises: Unusual noises, like rattling or banging, could be a sign of a serious issue.


5. Poor air quality: If you are noticing more dust, allergens, or other indoor air quality problems, it might be due to a malfunctioning HVAC system.

The cost of installing HVAC systems can range from $6,224 to $11,434 which includes the cost of AC unit, ductwork, local labor and project management charges. With each type of HVAC unit, the installation variables change by size, energy efficiency and brand you choose to install. Below are the average installation costs for different types of HVAC systems.

HVAC Costs by Combo System Type

HVAC Unit Installation Costs	Low Cost	High Cost
Central Air Conditioner	$6,465	$11,877
Ductless Split AC	$2,142	$3,936
Electric Furnace	$767	$3,523
Gas Furnace	$956	$3,870
Oil Furnaces	$3,325	$8,222
Heat Pump	$2,905	$7,449
Geothermal Heat Pumps	$15,000	$38,000

Read more about the cost of different types of HVAC units and what it entails.

Yes, there are a number of government rebates and incentives available for installing energy-efficient HVAC systems. These include:

1. Federal tax credits for energy efficient systems with up to 30% cost credit.


2. State and local governments offer rebates for energy-efficient HVAC systems


3. Utility company rebates with an amount depending on the efficiency of the system and the customer’s energy usage.


4. Manufacturer rebates or discounts on their energy-efficient products.

For more details on the rebates and incentives available, read Government Rebates for Air Conditioning and Heating.

The typical timeline for replacing an HVAC system is 1-3 days and can vary depending on several factors, including the size of your home, the complexity of the installation, and any required permits.

The process involves evaluation and planning by contractors, understanding permits, removal of old systems, installing new systems followed by testing and adjustments to ensure proper operation. 

Read about how to prepare and what to expect during an HVAC installation in detail with steps to consider.

When working with HVAC contractors look for red flags like unlicensed professionals, unclear quotes and high pressure sales tactics. A reputable contractor should be licensed and insured to operate in your area who can also provide references to previous work. 

Additional points to consider:

1. Unclear Quotes: Ensure the quote is detailed and includes all costs, including labor, equipment, permits, and any additional fees.


2. Excessive Upfront Payments: Avoid contractors who request a large down payment or the entire project cost upfront.


3. Negative Online Reviews: Research the contractor’s online reputation and look for any negative reviews or complaints.


4. Lack of Communication: If the contractor is unresponsive or difficult to reach, it may indicate a lack of professionalism.


5. Unfamiliar with Local Codes: Ensure the contractor is knowledgeable about local building codes and regulations.

Here are the steps your need to take once your HVAC is replaced:

• Observe System Performance: Monitor your new HVAC system closely during the initial weeks. Listen for any unusual noises, check for uneven heating or cooling, and ensure it’s operating efficiently.


• Allow for Adjustments: Some systems may require minor adjustments during the break-in period to optimize performance.


• Review Warranty Information: Carefully read through your HVAC system’s warranty documentation and keep record of relevant paperwork, like purchase receipts.


• Regular Maintenance: Schedule routine maintenance for your new HVAC system as recommended by the manufacturer.


• Air Filter Replacement: Regularly replace your air filters to maintain optimal airflow and indoor air quality.


• Preventative Measures: Take steps to prevent common HVAC problems, such as keeping outdoor units clear of debris and avoiding overloading the system.