What Should I Know About Purchasing a New HVAC System?
Well-maintained heating, ventilation, and air conditioning, or HVAC system, can last up to 15 years or more, so most homeowners do not make more than a couple of these purchases in a lifetime. During those fifteen years, technology changes so much that the criteria used for making one purchase will certainly have changed before the next purchase. Unless you work in this field, pulling together all of the relevant information can be time-consuming and confusing.
Here are seven frequently asked questions that should help prepare for the next steps in purchasing a new HVAC system:
1. Can someone give me the basics?
A central HVAC system will use several components to move heat. A refrigerant gas will move heat from inside the house to the outside during the cooling season. The same gas will move heat from outside the house to the inside of the house during the heating season. These two processes use a number of major components:
- The typical air conditioning system is called a split AC, since it is comprised of two units—one inside and one outside. The warm, circulating air encounters a bank of coolant lines containing the refrigerant gas which removes heat and cools the air. As a bonus, the process also removes humidity from the indoor air. The warmed gas travels through coolant lines to an outdoor unit with a noticeably big fan. The outdoor unit releases the heat from the gas and the cooled gas is recycled to repeat the process.
- The typical heating system is a hybrid of technologies, using two major components.
- A heat pump uses the same system used in air conditioning but reverses the process. The refrigerant gas moves heat from the outdoors to the indoors. This is the most efficient way to heat your home . . . until you run out of outdoor heat. A heat pump is effective until about 350 F, so a backup system is needed.
- A furnace provides the secondary heat source for the periods of time the temperature falls below the threshold of heat pump efficiency. The two most common heat sources remain electricity and natural gas/propane. Circulating air is exposed to the heat source, warming the air before distribution throughout the house.
2. How can I determine the right sized system for my home?
If you are replacing an existing HVAC system, you might be tempted to buy the same sized system installed in your home more than 15 years ago. That is not necessarily the proper decision. Nor should you purchase whatever is in stock in the local HVAC warehouse.
- An HVAC system should be “sized to fit” your living space. The proper size is determined using a formula based on building criteria and measurements, which include:
- The volume of your home, not just square footage. Tall or vaulted ceilings must be considered.
- The number and size of windows and doors. The R-value ratings of windows will also be considered.
- The amount and type of insulation make a difference.
- The number, size, and condition of ductwork will be measured.
- Your HVAC professional can explain everything you want to know about the criteria used to determine the size and explain unfamiliar terms, such as tons and BTUs.
- Getting the size right will determine efficiency and comfort for . . . well the next 15 plus years, so take your time. A system that is too small for your space will struggle to make you comfortable. Since it works harder than it should, it will wear quickly. A system that is too big for the space will also struggle to make you comfortable efficiently. It will cycle on and off quicker, waste energy, and the short cycles will not remove sufficient humidity during the cooling cycles. Take your time and get it right.
3. Am I required to replace the entire system at once?
Replacing the air conditioning and heating system at once is the best practice. Combining 15-year-old technology with cutting-edge components is a roll of the dice at best. New, eco-friendly refrigerant gases may not function in old system components. The new system will have sensors, detecting variations that were not considered in the past. So overall, the answer is, “yes, you should replace the entire system together.”
However, in emergency situations—such as a furnace failure in extremely cold winter—talk to your HVAC professional about emergency alternatives.
4. Is it necessary to replace the ductwork at the same time?
Ductwork was built into the very walls of your home before the walls were enclosed. Replacing ductwork would be very expensive and require a major disruption of your family life during replacement. Therefore, duct replacement would be rare and limited, except in the most extreme cases. Circumstances that might require duct replacement include:
- Ducts that are too small
- Ducts that are damaged
- Ducts that have developed restrictions, or
- Ducts that are too long
These problems would most likely present themselves before decision time; evidence of an airflow problem might figure into the decision to replace the HVAC system. If the ductwork is intact and functioning properly, it will not need to be replaced. Getting the ducts cleaned before the new system is a proper decision.
5. What should I know about filters?
The “V” in HVAC stands for ventilation. Ventilation refers to moving fresh, clean air throughout the house. Air filters and air purifiers remove airborne contaminants. Filter options include disposable filters, washable filters, and hospital-grade filters that provide very good indoor air quality. In-line air purifiers can also neutralize organic material, including mold, mildew, bacteria, and viruses. Talk with your HVAC professional about specific needs and preferences.
6. What should I know about thermostats?
Thermostat technology has provided remarkable flexibility, allowing homeowners to customize comfort and savings. It is now possible to program daily heating and cooling cycles that match your family’s schedule precisely. Keeping your home at the same temperature 24/7 does not make sense and it wastes energy and money. You can now schedule your furnace to:
- Lower the temperature while everyone sleeps, to improve sleep comfort and save energy.
- Lower the temperature while everyone is away, at school, or at work.
- Create a warming buffer to return the temperature to the desired comfort level right before the family wakes up or returns home.
- The combination of increased comfort and reduced cost make thermostat technology very helpful.
Most new thermostats are programmable, while Smart thermostats include a phone or mobile device app. A Smart thermostat adds many features, including the ability to change the temperature on the fly, should your schedule change. Check with your HVAC professional about thermostat options for your new system.
7. With so many HVAC companies, how can I choose the right contractor?
Many people CAN do the work but deciding who enters your home to help you make such an important decision is vitally important. Hopefully, you have been developing a relationship with an HVAC firm, someone you trusted to maintain your existing system. If not, here are some key criteria for choosing an HVAC professional:
- A contractor that represents trusted brands, that represents quality workmanship and customer service. Warranties should cover product and installation.
- A contractor with the necessary licenses, certifications, and insurance. Membership in national trade organizations, such as the American Society of Heating and Refrigeration and Air-Conditioning Engineers or the American Conditioning Contractors of America reflect a commitment to professionalism and continuing education.
- A contractor with good online and word-of-mouth references.
Have Questions About Purchasing a New HVAC System?
Northwind Air Conditioning and Heat can help with Replacing Your Furnace, Maintenance, and repair. Contact us and get the answers you need.
