Check For A Faulty HVAC Zone Control Board
The zone control board is the brain of your HVAC, communicating with all of the other parts in your system to keep it running smoothly. When the zone control board fails, you may notice inconsistent temperatures in your home or an error code on the control board. When that’s the case, it’s time for action.
How to check your HVAC zone control board
The zone panel is the communication hub for the HVAC system. It receives input information from several thermostats then sends commands to motorized dampers in the ductwork to divert the air, as well as directing the actual HVAC equipment to run. Since it must do all of the above it will be located very close to the indoor furnace or air handler.
There may be a clear cover allowing you to view indicator lights while it's running or the cover may have to be removed for access. Many zone panels use red and green LED lights to indicate whether or not the motorized damper on a specific duct is open or closed. Check yours to see if there are any red lights.
Your HVAC equipment gets it's commands from the zone control panel on a multi-zoned system. To verify if the HVAC system is working, it's best practice to set all of the thermostats 5℉ above or below the current room temperature. If you're testing your cooling system, you'll want to set it 5℉ cooler than the room. If you're testing your heating, you'll need to set it to 5℉ warmer than the room.
Give the system at least 10 minutes for any built in time delays to pass. After 10 minutes, see if the heating or cooling unit has turned on. If not, that could mean there is an issue with a tripped circuit breaker, tripped GFCI outlet to a condensate pump, or an issue with the zone panel itself.
A zoned system is actually several small duct systems working together with one common HVAC equipment system. The easiest way to check the source of zoning issues is to turn off all but one of the zones. For example, if your home has three thermostats, turn off two, then begin testing the one that's still on.
Does the airflow come out of the vents in the zone you're testing while the other two zones don't get any air? Is the air from the vents heated or cooled according to your temperature settings? If both of these statements are true, then you have tested one zone to be working as it should. If you're getting airflow from the vents in zones that should be off or the air isn't the right temperature, then the motorized dampers may be at fault.
After testing the first zone, repeat these tests on each zone in your house. If the system is showing the same issues in all the zones, that could mean that either the HVAC equipment or the zone panel itself is failing. You'll need to call in a technician to do futher testing to know for sure which is failing.
If your zone control board isn’t the issue, investigate other potential reasons for why your HVAC system isn’t working.
What To Do If Your HVAC Zone Control Board Fails
When your HVAC zone control board fails, you’ll want to call in a technician to come repair or replace it. Since the control board operates and connects to the rest of your HVAC system, the last thing you want to do is tamper with any parts that can damage your HVAC beyond repair.
NOTE: This content is for informational purposes only, and HomeX and its affiliates disclaim all liability related to it. If you decide to perform any tasks based on this information, you assume all risks, including the risk of loss or damage to property or personal injury.
Let's Get It Fixed!
Our virtual experts can diagnose your issue (for free!) and resolve simple problems.