The U.S. Department of Energy estimates that HVAC system zoning can save homeowners up to 30% in cooling and heating bills. A zoned system also gives you greater control of air conditioning and heating in the home. You can easily define the level of heating or cooling in each room, depending on how you use each space, for greater comfort.
An HVAC zoning system could be the ticket to your zoning needs. It’s a complex control panel and can feel a little intimidating for first-timers. However, it’s a straightforward gadget once you’re familiar with HVAC zoning.
The little board allows you to decide how much cooling or heating goes into each room while giving you complete control over further temperature adjustments.
What is an HVAC Zoning System?
There is only one thermostat in standard forced-air systems to control heating and cooling for the entire home. If the thermostat calls for cooling to 26˚C, the entire home is cooled to 26˚C, including the rooms you’re currently not using.
This approach to heating and cooling is not only time-consuming but also incredibly wasteful. Heating the rooms you don’t need eats up electricity watts without good reason. Opening too many outlets at a go can also take a toll on the HVAC system. Zoning systems solve this problem by allowing you to control the heating/cooling in each room independently.
The HVAC zoning system is an electric circuit board that forms the brain behind HVAC zoning. Think of it as the central processing unit in HVAC zoning.
It defines how the zoning design works and controls the entire process by regulating how much cool or warm air enters each zone.
How the HVAC Zoning System Works
Although the control panel is the central piece in the zoning jigsaw, the system comprises two other critical components, i.e., dampers and thermostats.
The motorized dampers open and close based on the zone thermostats’ demands, letting in or blocking warm/cold air from entering the specific zone. A single zone with multiple air ducts can have multiple dampers, each serving a different duct.
Meanwhile, zonal thermostats control the cooling or heating level in that zone and direct the damper(s) in that zone to open or close, depending on the settings. There are two ways to install zoning thermostats;
- Install one thermostat per zone: This is the simplest, most straightforward approach. Each zone gets one thermostat dedicated to that specific zone. You can conveniently control the heating and cooling in that zone via the dedicated thermostat. The only downside is that you must walk up to each zone to control the thermostat.
- Use a multi-zone thermostat + sensors: In this setup, the sensors relay information to the single thermostat, and the thermostat controls whether each zone gets heat or air conditioning. A vital advantage of this approach is that you can control multiple zones from a single location instead of going to each zone to control the thermostat. It’s slightly more convenient.
All the dampers and zone thermostats are wired to the central control panel, which receives and executes all cooling and heating requests. However, a few modern sensors and thermostats can be wirelessly connected to the panel. The panel connects to the HVAC system via the central thermostat.
Benefits of HVAC Zoning
HVAC zoning has many advantages over the traditional single-thermostat approach to cooling and heating. These include;
Zoned systems give you more control over the level of cooling and heating in each room in the home. Since each zone has its thermostat, you can raise or lower the heating/cooling in a specific room without interfering with the heating/cooling in other rooms. You can even switch off cooling/heating in the rooms you’re not actively using while keeping the process running in zones in active use.
Energy Saving Potential
Whenever you lower the heating or cooling levels in the rooms you’re not actively using, you’re reducing your overall energy consumption. You can even shut off the heating/cooling process altogether in the unused rooms for greater energy savings. As we mentioned in the beginning, homeowners can save up to 30% on energy costs this way.
Better Indoor Air Quality
As soon as you implement HVAC zoning, you no longer solely rely on convectional currents to transfer heat and cool air from one room to the next. Each zone is kept separate and heated/cooled separately. This prevents or slows down the spread of mold, pet dander, pollen, dust, and other airborne particles from one room to the next.
Enhanced HVAC Appliance Lifespan
One of the leading causes of accelerated HVAC appliance breakdowns and malfunctions is overuse. When you have the heater running at full throttle for six hours or more every day, you can’t expect the appliance to last long. It will wear down faster. Zoning reduces the demands on your furnace and air conditioners for a longer life of reliable use.
Zoning System Tips and Best Practices
As you shop for the best HVAC zoning system, you need to keep in mind that the key to ultimate convenience and maximum energy-saving is proper zoning while avoiding common mistakes. You’re not going to save 30% in energy costs merely by investing in a zoning system. You must zone the correct way.
The following tips and best practices should help you identify the best zoning system and implement the right zoning design for maximum impact.
Consider Two-Stage and Variable-Capacity Systems
As you shop around, you’ll notice that some zoning control systems support multi-stage zoning while others only support single-stage zoning. Obviously, you’ll need to match your HVAC system. If you have a single-stage air conditioner, you’ll need a control panel that supports single-stage cooling. For two-stage ACs/heaters, you need a panel that supports two-stage heating/cooling.
However, it’s always advisable to consider multi-stage HVAC appliances and pair them with multi-stage zoning panels. This way, you can run on, say, 65% capacity on LOW and 100% on HIGH. This approach guarantees more savings.
Replace or don’t Zone Single-Stage Systems
Single-stage HVAC systems are either off or running at 100% capacity; there’s no in-between. This design comes with a few challenges. For one, you can’t reduce energy use when the system is running at full capacity. If one or more zones are closed, the excess air will blow through the open zones, meaning – no savings!
Also, when you have all the heated air entering one zone, you may experience overheating or overcooling in the said zone. It may also cause the HVAC system to run in short but frequent cycles, potentially resulting in significant temperature swings and mechanical failure.
Avoid By-Pass Ducts and Dampers
The by-pass duct is a pipe that connects at one end to the trunk supplying heated or cooled air and the return air plenum at the other end. Typically, a damper is located in the middle of the by-pass duct to control cool/hot airflow. The ducts fully close when all zones are closed and partially or fully open when a few or all of the zones are open.
Though helpful to a degree, the by-pass duct and dampers pose several challenges in HVAC zoning. It doesn’t necessarily reduce heating or cooling in single-stage systems; the dampers can collect humidity and mold, and forcing cold air into the handler when the AC is running can cause the AC coils to freeze.
HVAC Zoning System FAQs
Is a zoned HVAC system right for you? Yes, if you have a two-stage or variable-capacity HVAC system with a variable-speed blower. Zoning systems are also useful when you have unoccupied areas and frequently experience temperature imbalance in the home.
Is HVAC zoning worth it? Absolutely. HVAC zoning dramatically reduces energy consumption. You can save up to 30% (some reports say even 40% is possible) on cooling and heating costs. Moreover, zoning enhances indoor air quality and substantially boosts cooling and heating convenience.
How much does a zoned HVAC system cost? The total cost, including thermostats, control panel, zone sensors, wiring, fasteners/tape, and tools/safety gear, is about $500 to $1,600 for a two-zone system and rises by an additional $100-$300 for every extra zone.
Can you add zones to an existing HVAC system? Yes, you can add zones to your existing HVAC system even if you have a single air handler or furnace connected to a single compressor or heat pump. Indeed, some zoning control panels allow you to create up to 20 new zones.
What are dampers in HVAC? HVAC dampers, also popular as duct dampers, are movable plates located in the ductwork that regulate airflow and redirect it to specific areas of the home as directed by the thermostats.
Does HVAC Zoning save money? Yes. The Department of Energy says you can save up to 30% of cooling and heating costs, while some studies put the figure at 30% to 40%.
Best HVAC Zoning Systems Reviews
The following are six of the best HVAC zoning systems to consider if you’re short on time. The prices range from just over $100 to over $300. However, all of them are tried, tested, and proven to be extremely effective.
1. UT-3000 EWC Controls Control Panel Ultra Talk Communicating Zone Panel
For most people who’ve worked with HVAC zoning systems before, the model UT-3000 from EWC is considered one of the very best.
It’s a 100% plug-and-play when connected to a communicating HVAC system and network thermostats. Better still, it supports multiple fuels, automatically recognizes equipment, and precisely controls air supply targets and limit set-points for greater peace of mind.
The control panel allows you to control two or three air zones with 42vac power open/close or spring-assisted motorized dampers.
Specifically, it targets 24-volt 2 heat/1 cool gas/electric systems or 2 heat/1 cool convectional or dual fuel heat pumps and effortlessly pairs with any communicating thermostat with the ClimateTalk open protocol. However, it also supports any other off-the-shelf 2 heat/1 cool heat pump thermostat or single-stage 24/volt heat/cool thermostat.
The zoning controller’s key feature is the LCD screen that scrolls to display the current zone thermostat demand input and HVAC system demand output. You’ll find four buttons below the LCD screen to scroll through the menu on the screen and select desired settings. The built-in, no-volatile memory recalls previous settings even after a power failure.
Five colored LED lights indicate the HVAC system status and the current operating mode, while another three green LED lights labeled zone 1, zone 2, and zone 3 indicate the dampers energized to open.
- Controls up to 3 zones
- Automatic heating/cooling changeover
- Status LCD shows current settings
- Multiple LED indicators
- A tad expensive
2. SmartZone-2L 2-Zone Controller Kit w/Temperature Sensor
ECOJAY produces some great zoning controllers, and their SmartZone series of products is especially awe-inspiring. This specific option, the model ZS2L, is especially an attractive solution if you’re on a budget.
It’s easily configurable and works for residential and light commercial applications. Moreover, it can support up to two cool and three heat systems.
Brightly lit LEDs provide comprehensive system status information and temperature from included supply sensors. Among other things, the LEDs will show you which dampers are open and which ones are closed. You’ll also learn the current operating mode.
A comprehensive display screen (LCD) shows modes and status. It also displays the purge/changeover, low and high limits, and supply temperature. A “Time & Temperature” staging function ensures maximum efficiency and user protection.
The zone controller is compatible with a wide range of equipment, thermostats, and dampers. Supported thermostats include single-stage, heat pump w/emergency heat, and gas/electric options, while supported dampers include spring-open (10VA), spring-close (10VA), and power-close (3VA). Supported output equipment include 2-stage coolers, 3-stage heaters, gas/electric units, heat pumps, and dual-fuel units.
Remember that there are two ZS2L zone controller kits to choose from, i.e., the ZS2L and ZS2L-T. The ZS2L kit includes the 2-zone controller only, while the ZS2L-T kit includes the 2-zone controller plus a supply temperature sensor (ASAS).
- Excellent technical support and documentation
- Economy Mode allows for a setback of all zones
- Start staging and limit protection
- 2nd stage lockout to eliminate by-pass
- No mention of warranty
3. Honeywell HZ221 True Zone Control Panel, Controls 2-Zone system
Another incredibly affordable zone controller kit is the Honeywell TrueZone HZ221. This control panel is designed for single-stage heat pumps with auxiliary heat applications and comfortably controls two zones using any Honeywell heat pump thermostat. However, the thermostat must be configured for a heat pump with a cool reversing valve to communicate to the zone panel correctly.
Similarly, it supports a wide range of dampers. These include spring-open and power-closed round ARD and rectangular ZD zone dampers, power-open and power-closed round MARD/RRD round zone dampers, and static pressure regulating round CPRD by-pass dampers. The transformer size limits the maximum number of dampers per panel.
Aside from thermostats and dampers, the panel connects to a 40V or 75V transformer (40V transformer is included) and Discharge Air Temperature Sensor (DATS) (also included).
The panel features multiple LED lights to help you understand what’s going on. You’ll need to check with the user manual for the complete description of all the LED functions.
However, for most operations (cooling, heating, fan, purge, and zones), the LED is off when the function is not in operation, solid (stable) when the function is ON and operating normally, and blinking when the function is ON but operating abnormally, such as when the DATS temperature exceeds 160˚F.
- Advanced, dual-fuel operation
- Discharge temperature (DATS) staging
- Variable-speed fan control
- Clean, professional installation
- 5-year manufacturer warranty
- A little complex to understand
4. Honeywell HZ432K TrueZone kit
For Honeywell lovers dealing with four or more zones, the TrueZone model HZ432K is one of the most advanced zone controller kits.
It’d designed for heat pumps and dual-fuel applications expandable to 32 zones (3 heat/2 cool) and, though complex inside, is simple enough on the outside for easy installation and use. The easy-to-follow digital display uses natural language to guide you through the installation steps. We’d still recommend professional installation, though.
The panel works with a range of programmable and non-programmable thermostats. The thermostats can be single-stage, multi-stage, or heat-pump housed. What’s important to remember is that it may not work with every thermostat. For instance, stage-3 heat is only controlled by certain thermostat types. A few thermostats may also fail to put the zoning panel into emergency mode, thus should be avoided.
It also works with most dampers, zone, or by-pass. However, the best dampers to consider are ARD spring-open/power-closed, MARD and RRD power-open/power-closed, and SPRD static pressure regulating dampers. The maximum damper VA per zone is 28.8 at 100˚F ambient temperatures and 16.8VA at 160˚F ambient temperature.
The required Discharge Air Temperature Sensors (DATS) and 40V transformer is included, though the zone controller can also work with 75V transformers. However, you’ll need to purchase the outdoor air temperature sensor and salve damper control relay separately. A 5-year warranty backs the product.
- Robust push terminals
- Variable-speed fan control
- Common sense LED indicators
- Advanced dual-fuel operation
- Expandable to 32 zones with TAZ-4 Add-a-Zone
- 5-year warranty
- Complex to understand
- Requires professional installation
5. SmartZone-4X Control – 4-Zone Controller Kit w/Temperature Sensor
Another excellent zone controller for four or more zones is the ECOJAY SmartZone-4X controller panel. It supports single or multi-stage cooling and heating, i.e., cooling up to two stages and heating up to three stages, and can be used with any HVAC equipment, including gas, electric, heat pump, and dual fuel appliances. It’s also easy to install and even easier to use.
Pushbutton, screw-less wiring means you can set up the unit in minutes. Simultaneously, the wide array of LED lights provide a comprehensive system of information and temperature for quick installation and convenient control.
The LEDs are color-coded on all wiring connectors to simplify troubleshooting. And, in case of any issues, you can always turn to the ACOJAY website for additional support resources and a technical hotline.
A key feature of the SmartZone-4X is the expandability to 20 zones. You can easily connect multiple 4X boards using the SmartLink to expand the unit into a 20-zone controller panel. Another notable feature is the smart staging and limit protection function. It uses a propriety time and temperature algorithm to state up and down movements effectively and efficiently.
It accepts different thermostats, including multi-stage and Wi-Fi enabled models and runs with any 24VAC damper, including 2-wire spring and 3-wire power models.
- Fresh air control at no additional costs
- Smart staging and limit protection
- Exceptional technical support and documents
- Expandable to 20 zones with the SmartLink bus
- Expensive at over $200
6. RCS Technology 2-Zone HVAC Controller for Standard Gas/Electric Systems
Finally, the RCS Technology model 001-00242 is a 14-.4-ounce, two-zone HVAC controller designed for smaller applications.
It effortlessly controls cooling, heating, and general air conditioning in different zones in the home and supports both gas and electric appliances. It works best with standard, non-power stealing single-stage heat/cool thermostats or RCS communicating thermostats.
The two thermostats connect to a single cooling and heating HVAC mechanical system, providing two independent zones of temperature control such that you can indecently control the mechanical system and motorized dampers in each zone. However, it’s only for use in residential settings and can only handle up to 5-ton (40 BTU) heaters/coolers.
An automatic changeover from cooling to heating and vice versa allows you to conveniently switch from heating to cooling as the year wears on.
However, priority is given to heating calls. We also love that the zone controller’s operations are fully automatic and transparent to the user. Each zone thermostat provides all the controls you need for the ultimate comfort.
Since the unit works by creating two virtually “separate” cooling/heating zones, it’s imperative that you buy the right thermostat and take time to study how it works. Fortunately, it supports a wide range of thermostats and dampers.
- Supports a wide range of thermostats
- Usable with most standard dampers
- Automatic cooling/heating changeover
- Handles up to 40 BTU
- Maxes out at two zones
If you’re using a central air conditioner or furnace, you should strongly consider a zoning system to distribute the heat and cool air throughout the home more effectively and efficiently. Zoning systems allow you to control how much cool/warm air enters each zone for optimal indoor climate control.
You can also minimize or cut supply to rooms not in active use to save energy. Although it may cost you up to $1,500 upfront, the potential savings down the line are worth the investment.