How Does a 2-Zone HVAC System Work?

how does a 2 zone hvac system work

Any homeowner would be delighted to have a switch system that allows them to independently control the temperature within different areas of the house. If there are different rooms in the house and some of them are unused or unoccupied, it would be practical to have a control system that gives them an option to exclude the unoccupied rooms from the air conditioner’s cooling or heating effect. This option not only improves the efficiency of the system unit but also reduces the cost of electricity. 


What Is Dual-Zone HVAC?

Zoning is a process of controlling your HVAC system in order to fully utilize heating and cooling effect. A zoned heating and cooling system breaks your house into different areas or “zones”, each one is controlled individually by a thermostat. This system utilizes multiple sensors, thermostats, and modulating dampers to successfully manage the temperature in various zones within your home. 

Here are some advantages of having a dual-zone HVAC: 


Lower monthly electric bills

The option to concentrate preferred temperature to occupied rooms and space and exclude the unused areas let you save on utility bills.


Less wear and tear on the system

An HVAC system that operates to cool the entire house including the used and unused areas, works harder than those used in a small range of space. Thus, the unit might not last long and might require frequent repairs and replacements in the future. 


Customizable heating and cooling

Having a two-zone or multi-zone HVAC systems allow each occupant to experience their individual temperature preferences. For instance, one person wants to stay in a cooler room while the other one prefers a less cold or a little warm temperature. 


Difference between the Dual-Zone AC & Heating and a Dual-Unit System

A dual zoned system has one unit that provides heating and cooling to multiple areas of your home. While a dual-unit system has two separate units that individually operate a single zone with separate, detached thermostats. This is ideal for houses or offices that require two completely separate systems like apartment rental units. Between the two, a dual-zone HVAC AC is more cost-effective both in utility bills and maintenance repairs. 


How Zoned HVAC Systems Work

One of the primary parts of a zoned HVAC system is a number of motorized dampers. These dampers open and close depending on the demands of the zone thermostats. These dampers are inserted into the ducts or can be installed at the air outlet for each room or zone. If multiple ducts serve a single room or zone. Multiple dampers can be controlled altogether for an individual zone if multiple ducts serve a single room or zone. The number of zones in a specific home can differ based on square footage, room design, number of floor levels, and how different rooms are being used. 

The next key part of the zone HVAC system is the zone thermostats. In homes with the existing thermostat, it is good enough to use it as a zone thermostat. As each zone is divided, there is a thermostat in every zone that controls the heating, cooling, and fan operation for its individual zone. The connection of the HVAC unit to the central control panel which is also connected to the dampers and thermostats, allows the unit to respond to requests from different or multiple thermostats. 

When the thermostat in a specific zone is tuned for heating or air cooling, the dampers in that zone will open to let the air flow into such an area. Otherwise, the dampers remain closed in the rest of the area. Only if there is a call for heating or cooling, a specific damper will open again. When the desired temperatures are reached in each area of the home, those dampers will be closed. And when every part of the home reaches the preferred temperature, the entire system will shut off. 

To further understand the concept of zoning, let’s compare it to having a light switch in every room of the house. You wouldn’t install a central light switch to control in turning on and off all the lights in the house. It would still be practical to have an individual switch for each light. The same is true for AC’s heating and cooling. It would be a waste of energy to have a single central thermostat turning on the heating or cooling for the entire house.