How Control Dampers for HVAC Manage Different Temperature Zones
Modulating airflow is crucial in modern commercial buildings. Control dampers, a widely used component of airflow modulation, are both essential and unobtrusive. Like valves in plumbing systems, these mechanical components allow certain amounts of gas to pass through ducting and pipes. The amount of gas depends on various factors, including manually operated controls. However, using the right design can make a large difference in terms of ensuring that exhaust exits the system properly, zones are ventilated and at a comfortable temperature, and more.
Single and Multi-Blade Dampers
For multi-zone temperature control, single and multi-blade dampers are crucial to ensure that various rooms only receive the desired level of air. Multi-blade systems, commonly termed “louver” dampers, are some of the most popular dampers available for HVAC engineers. They are commonly divided into opposed and parallel designs, meaning that either the louvers all rotate in the same direction, or some rotate in opposite directions. Opposed blade dampers are good for controlling varying rates of airflow through a given set of ducting, while parallel blades are most effective when they are either nearly fully shut or fully open.
Another extremely common variation is the single-blade, or butterfly, damper. This type of damper can control flow at very high forces and temperatures.
Diverter, Backdraft, and Inlet Vane Dampers
Although they can be very large in size, these three types of dampers help different components in different ways, rather than specifically moving treated air through to different zones. More specifically:
- Diverter or bypass dampers: These units form the shape of a “T” to redirect hot gases where their energy can be reused, such as in heat recovery systems, condensing processes, and others.
- Inlet vane dampers: Fans use inlet vane dampers to control the amount of air that goes into the system, such as a fan or a blower, and can help provide precise control of ventilation for flue gas or similar applications.
- Backdraft and pressure relief dampers: Both types of dampers are built so that air can only move in one direction, helping keep exhaust from backing up into the HVAC system or causing issues with the fans.
Safety Control Dampers for HVAC
Dampers also play a crucial role in the safety and maintenance of complex HVAC systems. The “guillotine” version drops a sheet of metal to completely block the duct, allowing for maintenance. Industrial dampers like bubble-tight designs offer the strongest seal of all. An industry-certified dampener can also promote fire safety. For more guidance on dampeners and fire safety, please consult with a certifying HVAC industry authority like UL.
Controls and Actuation
The level of control for dampers is crucial to both overall efficiency and safety. While it may be possible for a single technician to manually control a guillotine damper to isolate one zone for service, modern commercial HVAC systems require centralized administration to improve efficiency.
As a result, dampers are often electrically controlled from electronics connected to a central hub via one of several protocols like BACnet. This allows multiple zones to be monitored for both proper damper operation as well as sensors for other airflow and temperature concerns.
It’s crucial when considering which dampers to select for your HVAC system to ensure that they can be controlled using existing systems. We recommend using reliable, OEM actuators for control dampers from high-quality, trusted brands like Belimo.
Find Control Dampers for HVAC Systems
Affiliated Parts represents leading manufacturers of various control dampers for HVAC systems, and we understand how important it is to select the proper type during upgrades and repairs. To get a quote, call or text us at 877-928-2787 or email us at parts@affiliatedparts.com.
