Zoning Problems In Ducted Air Conditioning Systems: 3 Potential Causes

Ducted air conditioning systems with zone control functionality gives you the ability to cool different rooms to different temperatures and shut off the flow of cool air to rooms that aren't currently in use. When properly used and maintained, these systems can provide substantial energy savings.

However, zone control systems can suffer from mechanical issues, which can impair your system's energy efficiency and prevent you from precisely controlling temperatures in your building. If your ducted air conditioner's zone control system is not functioning as it should, the following underlying problems may be to blame:

Faulty Thermostats

If your building has ducted air conditioning with zone control functionality, each separate zone in the building will be equipped with a dedicated thermostat to control its temperature. If one or more of these thermostats fails, controlling the temperature in the affected zone(s) can become impossible.

If a thermostat's readout goes blank, it may simply require a new battery to get it up and running again. However, if the readout shows an error code, or does not respond to user input, there may be a fault with the thermostat's wiring and/or circuitry. These problems should be rectified by a professional air conditioning repair service.

If your thermostat appears to be functioning normally, but you cannot precisely control the temperature of the thermostat's zone, the problem may be caused by improper thermostat placement.

For example, if a thermostat is placed in a location adjacent to a different zone, cool air from the nearby zone may cause the affected thermostat to shut off before its own zone reaches the correct temperature. This is another problem that must be fixed by professionals, and the poorly placed thermostat will probably have to be relocated and rewired.

Dirty Duct Filters

The air ducts that channel cool air to different parts of your building are fitted with physical filters, which capture and contain any dust or particulate matter passing through the duct. If these ducts are not cleaned and/or replaced regularly, they can become clogged with solid debris. This will prevent cool air from reaching the zone served by the affected duct. 

If some zones in your building require more cool air than others, the filters in these zones are likely to become clogged more quickly. If you find that your zone control system is not functioning properly in the most used areas of your building, dirty filters may very well be causing the problem. Fortunately, replacing dirty air filters is relatively straightforward and inexpensive.

Malfunctioning Zoning Gates

The ducts of your zoned air conditioning system will also contain zoning gates, physical barriers which open and close to redirect the flow of chilled air to where it is needed. These gates can also become clogged with debris over time, preventing them from functioning properly and undermining the effectiveness of the zoning system. They can also become jammed open or closed if their wiring or circuitry fails.

If your system's zoning gates are jammed or malfunctioning, you should call in a professional air conditioning repair service to fix them as soon as possible. Your ducts may need to be partially disassembled in order to inspect and repair the faulty gate(s), and attempting to dismantle ductwork yourself can cause serious (and expensive) damage. Contact an air conditioning repair service for more information.