Author: Jeff O'Hara
You learn many things when you’re the blog writer for a plumbing and air conditioning business. To borrow a phrase from the internet, “I was today years old when I learned how many different ways there are to heat your home.” I’m like most people who live in a warm climate; as long as whatever kind of furnace I have is in working order on the few cold days we get each year, that’s all I need to know. Understanding the type of heat source your home uses and how the heat is distributed and controlled will help keep you from spending too much on heating system repairs and new heating system installations.
While it seems as though central HVAC systems have always been a feature in our homes, they only became a standard part of new home construction in the mid-1970s. Before that, most households relied on an oil-fired furnace that utilized heavy steel radiators that delivered heat via hot water or steam distribution. The in-window electric air conditioner was introduced just after World War II in 1945, allowing the population of the southernmost states in the U.S. to grow exponentially.
How Many Types of Home Heating Systems Are There?
There are currently seven different types of home heating options, all of them being highly effective when professionally installed. Depending on where you live, variables like local climate, available energy sources, and initial cost considerations will determine the best home heating option for you. In Houston, the most common type of home heating appliance is the gas-powered central furnace, which shares common ductwork with the home’s air conditioning system. From there, heat pumps, boilers with radiators, fireplaces, and electric radiant heaters fill in the gaps where a whole-house heating system is impractical to install.
Furnaces
A furnace has become a catch-all term used to identify the heat source for a particular structure. In most cases, a stand-alone A wide variety of firing methods are used to generate heat, from natural gas, fuel oil, or LPG (liquid petroleum gas) as the most common, with wood and coal among the least common.
In North American homes, the trend has been toward installing multi-function HVAC systems in new construction residential homes. In homes built before the 1970s, heating, ventilation, and air conditioning were separate entities, with specialized appliances needed for each application. While popular in the mid-twentieth century, oil-fired furnaces have fallen out of favor thanks to cleaner-burning natural gas or electrically powered units. Furnaces in turn of 20th-century homes circulate hot water through baseboard radiators, and some still older homes use heavy steel steam radiators with a central boiler.
Heat Pumps
Heat pumps are popular in the southern states, as they are reversible systems that can cool a home as well as heat it. Instead of using a refrigerant to cool incoming air drawn from outside, heat pumps use a series of metal coils to draw heat out of a cold space and transfer it to another area. Heat pumps work like large refrigerators, just turned inside out, and electrical fans are employed to distribute the pre-treated and treated air throughout the system.
Stand-Alone Radiant Heaters
For those who do not have a central furnace in their home or has one that is having a hard time meeting demand, there are several space heating options available. While it is possible to heat your entire home with electric or kerosene heaters, they are not designed to heat multiple rooms or maintain the temperature over an extended period. Space heaters are intended to be supplemental to a more efficient and more powerful whole-house heating system and most usually found in rooms at the end of the home furthest from the furnace.
Radiant Kerosene Heaters: Single room space heaters that use kerosene can release toxic gases into the air if the wrong fuel/air mixture is present. There is also an increased risk of fire from the high temperatures on the heater’s surface and from the open flame burning the fuel. Kerosene space heaters should never be left unattended by a responsible adult at any time they are being used. Carbon monoxide poisoning is possible when using a kerosene heater, as the heaters are most used at night while people are sleeping. Most kerosene heater manufacturers recommend leaving a window or exterior door cracked slightly to allow a steady oxygen supply to reach the heater.
Radiant Electric Heaters: Electric space heaters have their own list of shortcomings, the most notable being the inherent inefficiency of heaters operating at 110 volts. The heat generated by electrical resistance cannot achieve a high enough operating temperature to effectively warm a room at 110 volts, the standard for residential power connections in the U.S. In homes that use an electrically powered furnace that needs to generate more than 15,000 British Thermal Units (BTUs) will require the same 220-volt service that most clothes dryers and electric stoves use.
Things to Consider When Choosing a Home Heating System
Whether you’re replacing an existing home heating system or looking to add central HVAC to your existing home, several items need to be on your contractor’s list of “to do’s.” Size really does matter when it comes to HVAC systems, and accurate measurements need to be taken of each room, taking ceiling heights into consideration. The way an HVAC company determines the size of the unit required to heat and cool the home effectively and efficiently is first to measure the square footage of your floor space.
They say the best customer is an educated consumer, and just a little bit of research can pay a hefty dividend. With a big-ticket purchase like an HVAC system, the homeowner needs to do their due diligence to make sure they don’t have too small or too large of an HVAC system. For example, I’ve broken down how to acquire the measurements you need to take, including some variables, and come up with a quick formula to help you determine your HVAC needs.
What Size System Do I Need to Heat My Home?
To best determine the size of the heating system you need, you need a measurement of your home’s floor space, in overall square feet. Measure each room with a tape measure, take the length and width measurements, and multiply them by each other.
Example: #1
Bedroom #1: Size 10’ X 14’ = 140 Square Feet
Bedroom #2: Size 15’ X 20’ = 300 Square Feet
Kitchen: Size 15’ X 12’ = 180 Square Feet
Living Room: Size 20’ X 20’ = 400 Square Feet
Bathroom #1: Size 10’ X 12’ = 120 Square Feet
Total Floorspace: = 1,140 Square Feet
HVAC systems need to be appropriately sized to sufficiently cool or heat the structure they are installed in. The unit of measurement used in HVAC systems is the British Thermal Unit (BTU), defined as “the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.” It takes approximately 25 BTU’s to heat one square foot of floor space with a ceiling height of eight feet or less.
At this point, we’ll multiply the overall square footage of your home by 25 to get the minimum BTU requirement for your home.
Example #2
Total Floorspace: 1,140 Square Feet
X 25 BTU’s Required for Heating 1 Square Foot of Space
28,500 Minimum BTU’s Needed (8-foot Ceilings or Lower)
The home in our example is going to require an HVAC system with a BTU measurement of 28,500. This is assuming a ceiling height of 8-feet or lower. In homes with ceilings higher than 8 feet, multiply your required minimum BTU measurement by 25% to allow for heating the additional cubic footage of the room.
Example #3
Minimum BTU’s Required: 28,500
High Ceiling Adjustment: X1.25
35,625 Minimum BTU’s Needed (w/ 8′ – 10′ Ceilings)
Since most homeowners replace their furnaces and air conditioning units simultaneously, you can use the data from the heating measurements to determine the air conditioning unit’s size that you’ll need to install for optimum comfort. By taking the number of BTU’s required to heat your living space and dividing that number by 12,000 to arrive at the tonnage needed for an A.C. system in that area.
Example #4
BTU’s Required to Heat Home: 35,625
/12,000
2.968 Tons, requiring a 3 Ton AC Unit.
It’s a crucial step in the HVAC system installation process to select your home’s proper units. Installing too small of a furnace in your home will require that furnace to run for much longer cycles, yet never heating the house to a comfortable temperature. Too large of a heating system will result in rooms heating up too fast, causing the unit to shut down too soon, only to restart it quickly as the heat dissipates from the room. This “short-cycling” of your furnace will cause premature wear and tear on all components within, leading to expensive repairs.
If it’s time to consider a brand-new heating, ventilation, and air conditioning system, call Nick’s Air Conditioning Services for help first. We’ll take the time to inspect your current HVAC system, assess its current condition, and make recommendations to get the right components installed in your home. We hire only licensed and experienced technicians to ensure your satisfaction and background check each one to ensure customer safety.
Have a question or two of your own regarding residential heating systems and how to pick the right one for you? Call Nick’s a call today at 713-868-9907.