HVAC LINGO FOR HOMEOWNERS PART 1 OF 2

HVAC LINGO FOR HOMEOWNERS PART 1 OF 2

Every profession out there has its own lingo, for example my wife, who has been a Nurse at St Charles for over 20 years, will try and tell me about her day and I find myself just nodding my head and wishing the conversation had subtitles. Because the truth is, I have no clue what she is talking about when she uses words and acronyms that people in her industry use every day, not thinking that the rest of us have never heard nor know what Epistaxis is, she could have just said Nosebleed, but what is the fun in that.   The HVAC industry, although not nearly as complicated as the medical industry, has some HVAC jargon that can leave a homeowner confused and not feeling confident in making a financial decision, especially if they have never had to deal with the HVAC Industry in the past. So, the team here at Cascade Heating, thought it may be helpful to put a series of blogs discussing topics that we run across daily, and think it may be helpful for a homeowner doing research to become informed about available options and what is important to know before making the decision. 

Here is some common HVAC Jargon that you may hear from a Comfort Consultant and other members of the HVAC industry when coming into your home. My intent is not to get in the weeds too much but provide enough information that you have a basic understanding of what they are talking about and how it works. The first part will cover the primary components of a system and part 2 will go over other aspects of the system that are important to understand when trying to decide about your HVAC system.

Air Handler (Indoor Unit)

• What is an Air Handler: The air handler is just a metal or composite box with a blower (fan) and is designed to move air through the duct system. When it includes an indoor coil, it can be used for heating and cooling when paired with a heat pump. Many air handlers today come with a coil already installed at the factory. If heat strips are added, it can be used as a primary heat source. This is sometimes referred to as an electric furnace.
• Air Handlers are used to provide forced air to a home that does not have natural gas or propane options available.

Heat Strips

• Heat strips have several names in our industry. So, if you hear, supplemental heat, emergency heat, auxiliary heat, or backup heat, they are referring to heat strips.
• Heat strips are heating elements that are installed in the air handler that can be the primary heating source (electric-only systems), or when paired with a heat pump, serve as backup heat.
• How they work with a heat pump: heat strips turn on automatically when your heat pump cannot maintain the temperature inside your house due to the outside temperature being too cold. Or if there is a large temperature difference between your indoor temperature and the set point on your thermostat. This is referred to as auxiliary heat.
• Emergency Heat: (EM Heat) In most cases you can manually switch your thermostat to emergency heat. This usually turns off your heat pump and runs the heat strips as your primary heat source. This can be helpful if your heat pump is not operating properly.
• Heat strips are great for comfort and backup heat but typically cost more to operate than the heat pump.

Heat Pump (Outdoor Unit)

• What does a heat pump do? It pulls heat from the outside air and distributes it into your home through your indoor coil and blower. It can also cool your home in the summer.
• Why choose a heat pump? A heat pump is a much more efficient way to heat compared to using electric heating elements (heat strips) alone, because it moves heat instead of creating it.
• Heat pumps come in several comfort/efficiency options. The most common are single stage, 2-stage and variable capacity (variable speed/inverter)
• Singe stage: Runs at one heating/cooling output. Often a good fit for single level moderately sized home that does not need zoning. You can use a single stage heat pump on a 2-story home, but the temperature differences between floors become more noticeable. Cascade Heating does not recommend singe stage equipment with zoning.
• 2-Stage: Runs at lower output most of the time and a higher output when needed. This helps improve comfort and efficiency during the milder days and can be a better fit for homes that would benefit from zoning.
• Variable capacity (often called variable speed/inverter): These units adjust output in small increments to match what your home needs. In general, they offer the best comfort, quietest operation, and efficiency and when paired with the right controls and zoning approach, can make a noticeable difference in comfort.
• Is variable capacity worth it? Keep in mind, you are often buying comfort. Variable capacity is extremely efficient, but depending on your usage and utility rates, the upfront cost may be more than your energy savings over time.
• You will typically hear two things when someone is talking about heat pump efficiency: SEER/SEER2 and HSPF/HSPF2. This is miles per gallon your system gets.
• SEER/SEER2: Tells you how efficiently the unit cools over a typical season. The higher numbers generally reflect lower operating costs. These can range from 14 SEER/SEER2, being the least efficient, 20+ SEER/SEER2, the most efficient.
• HSPF/HSPF2: How much heat the system delivers over the heating season compared to electricity it used. The higher the number also generally means lower operating cost. This can range from 7.5 HSPF/HSPF2 to 11+ HSPF/HSPF2.

Furnace (Indoor Unit)

• Furnaces come with many different options. Efficiency typically ranges from 80% AFUE to around 97-98% AFUE. They also come in many comfort levels: single stage, 2-stage, and modulating (variable speed capacity). The most common fuel types are natural gas and propane and in some areas oil.
• AFUE is a measure of seasonal efficiency. In basic terms, if you have an 80% furnace, about 80% of the fuel’s energy is being used to produce heat and the remaining potential energy is lost, mostly out of the flue/exhaust pipe.
• 80% of furnaces will have a metal flue/exhaust pipe from the furnace to the outside and 90% plus furnaces will have PVC flue/exhausts. This is why they are called condensing furnaces; they can pull more heat out of the gases, cooling the exhaust enough that it condenses.
• If you are considering switching from 80% to a condensing furnace, here are some things to consider.
• Condensate Drain: a condensing furnace produces a lot of water that needs to be drained to an approved location. In many homes this is the laundry washer box or tied into the drain under a sink. To do this, most cases require a mechanical pump.
• Venting changes: The flue venting will need to be changed to meet the manufacturers’ requirements, and in some cases finding a suitable location to terminate the flue to the outside can be difficult.
• Value vs payback: If you are upgrading for efficiency, I would recommend that you look at your overall gas bill and estimate how much your furnace is contributing to seeing whether the extra efficiency savings will outweigh the installation costs and added complexity of the system.

Air Conditioner (Outdoor unit)  

• What does an air conditioner do? It removes heat from inside your home and releases it outside.
• Air conditioners come in several comfort/efficiency options. The most common are single stage, 2-stage and variable capacity (also known as variable speed/Inverter)
• Singe stage: Runs at one cooling output. Often a good fit for single level moderately sized home that does not need zoning. You can use a single stage on a 2-story home, but the temperature differences between floors become more noticeable. Cascade Heating does not recommend singe stage equipment with zoning.
• 2-Stage: Runs at lower output most of the time and a higher output when needed. This helps improve comfort and efficiency during the milder days and can be a better fit for homes that would benefit from zoning.
• Variable Capacity (variable speed/inverter): These units adjust output in small increments to match what your home needs. In general, they offer the best comfort, quietest operation, and efficiency when paired with the right controls and zoning approach they can make a noticeable difference in comfort.
• Is Variable Capacity worth it? Keep in mind, you are often buying comfort. Variable capacity is extremely efficient, but depending on your usage and utility rates, the upfront cost may be more than your energy savings over time.
• SEER/SEER2: Tells you how efficiently the unit cools over a typical season. The higher the seer the more efficient the unit. This can range from 13 SEER/SEER2, being the least efficient to 20+ SEER/SEER2, the most efficient.

Coil (Evaporator coil/Condensing coil)

• A coil is required for an air conditioner or heat pump to function. They are installed so that the air from the indoor unit fan/blower pushes or pulls indoor air across it.
• What does it do? In heating mode (heat pumps): the outdoor unit absorbs the outside heat, and indoor coil gives the heat to the home. In cooling mode (heat pumps and air conditioners), the indoor coil absorbs the heat from your home’s air, and the outdoor unit releases that heat outside.
• Typically, you will not see options for this unit listed on an estimate because they match them to the outdoor unit. The outdoor unit you choose will determine what matching coil is included.

Filters

• Filters come in all shapes and sizes; Their primary purpose is to protect the equipment, and their secondary purpose is to improve air quality.
• What is a MERV rating: It is a standardized rating that tells you how well an air filter captures particles. The higher the MERV rating = catches smaller particles and more of them.
• What filter should I get? Most homes do best in the MERV 8-11 range. It is a good balance of filtration and air flow for many systems.
• What if I want a MERV-13 Filter? Higher MERV filters can be more restrictive, especially in the 1-inch size. If air flow is restricted too much it can cause comfort issues, higher energy use, increased maintenance/repair cost, and even premature equipment failure. If you want to move to a higher MERV filtration, it is best to have an HVAC professional check your system’s current filter size, ducting and airflow to make sure it is a good fit.
• Another way to improve air quality without increasing the MERV rating is to add an electronic air cleaner to your duct work. There are serval options in the market today that allow us to tailor what best works for you and can help increase the efficiency of your existing filter while also providing many other benefits.

Thermostats

• If you are upgrading your system, it is best to talk to your HVAC advisor about the best thermostat for your application. Some of the more advanced systems today require a specific thermostat to function properly. If you are looking to just upgrade your thermostat, it is still a good idea to talk to an HVAC professional before you purchase one. We spend a lot of time on the phone letting homeowners know that the thermostat they purchased is not compatible with the system they own.