Your HVAC system may have a very tough time adequately heating or cooling a large home. If your entire home is heated or cooled by a single central unit, this unit must be able to produce a sizable amount of air, which uses a lot of energy. These single-unit systems are common, but frequently they lead to inefficient heating or cooling and high energy costs because they have to operate laboriously, especially in larger homes. Many households have started zoning their HVAC systems as a defense against this.
Why Do We Zone Our HVAC?
By separating various duct and vent systems, zoning is the technique of segmenting the HVAC system in your home. Your system needs to heat or cool a much smaller area at a time when your home is properly zoned, so it runs less frequently and costs you less money. Since your system will have a lot easier time heating or cooling the hardest-to-reach rooms in the house, it also typically leads to higher comfort. This can be a big advantage for houses with multiple stories. Due to the fact that heat rises, homeowners have the option of only air conditioning the upper areas when necessary and only heating the ground floor during the winter.
While it’s very likely that you can zone your home’s HVAC system and ductwork, zoning might come with some additional issues, so it might not be the best option. The type of heating or cooling system you have should be the first thing you check, paying close attention to how the blower motor functions.
HVAC systems often fall into one of three categories:
Systems That Are Single-Stage
The two options for single-stage systems are on and off. The blower motor operates at maximum speed and power when your system turns on until the thermostat tells it to turn off once more. In most homes, especially those with older HVAC systems, this is very typical. When you have a high-power single-stage system, it is not recommended that you zone your HVAC system.
Consider this hypothetical 30,000 BTU air conditioner as an example. If you divide your home into two zones, your 30,000 BTU system will suddenly be twice as powerful as it needs to be because each zone would only require about 15,000 BTUs to cool. Although it may not seem like a huge concern, systems that are too massive for the zone they are managing frequently start short-cycling, or turning on and off quickly. As a result, your HVAC system experiences significant wear and tear, blower motor damage due to excessive amperage draw, motor, igniter, and inducer burnout, furnace overheating, air conditioner coils freezing into a block of ice, and numerous other issues that necessitate time-consuming and expensive repairs.
When some less respected HVAC repair and installation businesses make the offer to zone your system on a single-stage setup, they frequently either don’t know what they’re doing or show up when the system breaks down and offer expensive repairs while still trying to sell you a real zoning system. Others will advise installing a dump damper, which recycles already-conditioned air but still causes short-cycling and the related wear and tear. This device allows a single-stage HVAC system to operate smoothly and reduce motor blowout.
Systems In Two Stages
Two blower levels are available in a two-stage HVAC system: full-blast and a decreased capacity (usually around 65 percent , depending on the manufacturer). One of these systems will operate at a reduced capacity when a smaller zone needs heating or cooling, addressing many of the problems that a single-stage system may have.
These programs are not flawless, though. When cooling or heating a zone that makes up less than 65 percent of your house, your system will still start to short-cycle, putting additional strain on the blower motor and other parts.
A modulated system is the greatest choice for a home with multiple zones when it comes to heating or cooling. Depending on the manufacturer, modulating furnaces can operate at full capacity all the way down to 35 percent (or as low as 25 percent for air conditioners). The greatest choice is this since your system will adjust to each unique zone in your house. You won’t have to worry about the usual issues that arise from zoning a single-stage or certain two-stage systems if you zone your home so that each section is at least 35 percent.