Maichle’s Guide to HVAC Heating Systems

Modern home heating systems are undoubtedly a lifesaver in colder climates. While home heating isn’t cheap, it’s hard for most folks to imagine making it through winter without it. However, with an overabundance of different home heating technology available, all seemingly designed for the same basic purpose, it can also be hard to determine what type of heating system is best suited for your exact needs, let alone understand all of your options. To help homeowners do both with ease, we’ve put together our own comprehensive guide to HVAC heating systems. 

Modern home heating systems are undoubtedly a lifesaver in colder climates. While home heating isn’t cheap, it’s hard for most folks to imagine making it through winter without it. However, with an overabundance of different home heating technology available, all seemingly designed for the same basic purpose, it can also be hard to determine what type of heating system is best suited for your exact needs, let alone understand all of your options. To help homeowners do both with ease, we’ve put together our own comprehensive guide to HVAC heating systems. 

Types of HVAC Heating Systems 

There are several different types of heating systems that can be used for home heating purposes, all with their own nuances, advantages and limitations. Before determining whether or not you have the right system, it’s important to understand what type of system you have, what other types of systems are available and the differences between these various system types. To start, heating systems can for the most part be divided into one of two main umbrella categories – forced air systems and water-based heating systems – before being further subdivided by narrower, more specific system types.  

Forced Air Systems

The far more common of the two main types of home heating systems, forced air systems are named for their main heat source (air) and the process by which it is distributed by being blown, pulled or otherwise forced through a series of ducts. Forced air systems use a variety of means and fuels to pull in air and heat it up before sending it off into your home, the specifics of which we’ll explain for each individual system. After the air is heated, the air travels through the distributive ductwork that connects to a series of registers and air vents throughout the home. These registers and vents are where the warm air is forced out and into a designated room or area, creating the well-known warming effect we all cherish so dearly.

Furnaces

Central heating furnaces are the most traditional and (still) most popular type of heating system in American homes. Powered by electricity, natural gas or oil, furnaces work by either burning fuel or using electrical power to create hot air, which is then distributed to various rooms of a home via air ducts, vents and registers. While furnaces come equipped with a number of self-regulating switches and controls, you can adjust its primary output via your thermostat.

Since furnaces are the most typical type of home heating system, one advantage they hold is that most homes are already equipped with all the necessary components for these types of forced air systems, including ductwork.

Heat Pumps

Heat pumps function just like air conditioners in that they both use compressed refrigerants to heat or cool your home simply by transferring hot air into or out of your home. To distribute warm air throughout your home in the winter, heat pumps use the same forced air system as furnaces via a series of ducts and vents.  

The source of hot air depends on which of the two main types of heat pump you have – air-source or ground-source. Air-source heat pumps pull in air from outside in the winter, while ground-source heat pumps (also known as geothermal heating systems) pull heat from underground where temperatures remain more consistent year round. The cheaper and more easily installable of the two, air-source heat pumps are far more common. Despite their initial costs and extensive installation process, ground-source heat pumps are far more energy efficient and eco-friendly, so they can eventually save you money in the long run.   

Hot Water HVAC Systems

Hot water HVAC systems, also commonly known as hydronic systems, are so designated due to the fact that they use water as their main heat source, as opposed to air. While water heaters used to provide warm water are a standard feature in most US households, hot water HVAC systems used to warm entire homes are far less common than their air-based counterparts. 

The fact that they aren’t as widely used means the majority of pre-built homes haven’t been set up to handle them beforehand. This means installing an entirely new system from scratch in most cases, which will obviously require larger costs. 

Boilers

Boilers differ from furnaces in terms of both their heat source and the distribution systems they use. Instead of air, boilers use hot water as their heat source. Instead of air ducts, boilers distribute heat throughout a home via a system of pipes connected. Instead of vents and air registers, these pipes feed the hot water into radiators, which in turn warm the air in your home. 

Boiler HVAC systems don’t come cheap, but they also have distinct advantages that could, in some cases, make the extra cost worthwhile. If you want the ability to program multiple climate control settings at the same time for different floors or rooms in the same home via multiple respective thermostats (commonly known as zone heating), this is much easier and cheaper to do with a hydronic system like a boiler.

Radiant Floor Heating

There is also a heating system known as radiant floor heating that uses boilers and water pipes in a similar manner. The only difference is that with radiant floor heating, the water feeds into plastic tubing beneath the floor as opposed to radiators. The radiant heat produced then warms your home quite literally from the ground up.  

Again, the cost to install and maintain this type of system isn’t cheap, but it has its advantages, such as being more easily adaptable for zone heating purposes. Radiant floor heating is also especially nice for homes with a lot of hardwood, tile or stone flooring. These types of floor would otherwise normally be cold to the touch during chillier seasons, adding to the discomfort created by the cold. 

Ratings for HVAC Heating Systems 

One of the most accurate ways to gauge the comparative performance levels of various heating systems is to refer to their ratings. With several different types of ratings all measuring different aspects of system performance, it’s important to be aware of exactly what each rating is measuring and whether it falls short of, meets or exceeds industry standards. 

What are HVAC ratings and what do they mean? 

Different kinds of ratings are measured using different variables and constants, but most more or less reflect the overall efficiency and performance of the HVAC system in question. There are four main types of HVAC ratings to be aware of, the varying metrics of which we’ll get into more detail on here shortly. Those 4 types of ratings are Annualized Fuel Utilization Efficiency, Seasonal Energy Efficiency Ratio, Heating Seasonal Performance Factor and Minimum Efficiency Reporting Value. 

Types of HVAC Ratings

Annualized Fuel Utilization Efficiency

An Annualized Fuel Utilization Efficiency rating (or AFUE rating) essentially measures the average ratio of input fuel vs. output heat for furnaces and boilers. This ratio is then expressed as a percentage representing the average amount of fuel being effectively converted to usable heat over a year. So, a system with only a 50% AFUE rating has a fuel to heat ratio of 2:1, meaning you’re only getting half as much heat as you would if your system’s fuel consumption was at 100% efficiency. Fortunately, industry standards require a minimum 78% AFUE rating on all new furnace and boiler models. Typical AFUE ratings run from 80%-90%, while high efficiency models can boast AFUE ratings of up to 97% efficiency. 

Seasonal Energy Efficiency Ratio

Defined by the Air Conditioning, Heating, and Refrigeration Institute in 2008, Seasonal Energy Efficiency Ratio (or SEER) is the most widely recognized HVAC ratings system in the US. Typically associated with air conditioners as opposed to heating systems, SEER ratings measure the ratio of maximum cooling output compared to electrical energy input over a typical cooling season, which is then converted to numeric ratings that range from 1 to 27. Older air conditioners have lower SEER ratings of around 8 or 9, while current industry standards require a minimum SEER rating of 13 of 14. On the higher end, more energy efficient models can boast ratings anywhere from 16 SEER to 22 SEER. 

Heating Seasonal Performance Factor

Heating Seasonal Performance Factor (or HSPF rating) is a rating system that is essentially the equivalent of an SEER rating, but for heat pumps instead of air conditioners. HSPF measures the maximum efficiency of a system by calculating the ratio of heat output compared to electrical energy input over the course of a heating season. These ratings are expressed numerically, with decent systems clocking ratings anywhere from 8 to 10, and the most energy efficient heat pumps boasting ratings of 10.2 and higher. 

Minimum Efficiency Reporting Value

The Minimum Efficiency Reporting Value (or MERV ratings) system differs from the others on this list in that it doesn’t measure the efficiency of your HVAC system as a whole but rather focuses on the effectiveness of air filters. Expressed on a numerical scale ranging from 1-16, MERV measures the amount of unwanted air particles (allergens, contaminants, etc.) that a given filter is able to trap. Filters with higher MERV ratings can trap smaller particles than filters with low MERV ratings, resulting in a higher percentage of particles being trapped and cleaner air being filtered through. Filters for residential units can have MERV ratings anywhere from 6-12, while scientific and medical facilities often come equipped with specially designed air filters that boast MERV ratings of 13 and higher.. 

Choosing the Best HVAC Heating System

Now that you know all about different types of heating systems, their functions and how they are rated, the question remains: how do you choose the best system? The simple but frustrating answer to this question is that it all depends. 

A number of different factors will come into play when determining the best heating system for your home, including but not limited to: the size, layout and location of your home, what (if any) existing types of heating systems are already in use there and whether or not you want to switch to a new system type, what kind of a budget you’re working with and what exactly you’re trying to achieve by investing in a new system (ie. saving money, increasing comfort and convenience, reducing carbon footprint, etc.). All of this information will narrow your options down to make the final choice a lot easier. 

Once you’ve reduced the number of options to a select group of potential systems that you know meet all of your criteria, you can look to things like consumer ratings and reviews to help weigh your remaining options. You can also ask a trusted HVAC pro for a recommendation, as their knowledge, expertise and first hand experience with various systems and system types grant them a much more informed perspective than your average homeowner. 

Closing Thoughts 

Whether or not you’re looking to replace your home heating system at the moment, we hope this article has helped you to become a more informed homeowner, especially when it comes to keeping the house warm. If you are considering a new heating system and happen to live in or around the Delaware Valley region, Maichle’s HVAC is here to help, from evaluations and recommendations to installations and upkeep. To learn more, visit www.maichleshvac.com or give us a call at (302) 328-HVAC to get started today!