We have worked with Variable Air Volume (VAV) Diffusers from Acutherm for 20 years now (they have been around since 1978). In the start there was one option; a stand alone Thermally Powered VAV Diffuser. It was called the Therma-Fuser. That was it and it worked very well. Today we have choices.
There are at least six ways to design a system and a fairly wide range of Building Automation System (BAS) options available. Whether you’re looking for simple individual temperature control, requiring no energy for operation, or a full-scale networked system, it’s available now. Here’s a brief overview of the six basic options.
Option 1: Therma-Fuser™ stand alone diffusers
This is as simple as it gets. This configuration provides the comfort and energy savings of individual temperature control at the lowest cost available. Low cost and low maintenance makes it a long time favorite. In this case the BAS is simply controlling supply air temperatures to the VAV Diffusers.
Option 2: Therma-Fuser™ stand alone diffusers with Room Temperature Sensors
Same as above and also monitoring room air temperatures with the BAS. The BAS can read an analog room temperature signal from a sensor installed in each diffuser. In this case the BAS is simply monitoring the system and controlling air temperatures.
Option 3: Therma-Fuser™ stand alone diffusers with Wall Adjusters
Adjust room temperature set point with the BAS.
The BAS can read and reset the room temperature setpoint of each diffuser using analog signals from an Acutherm Wall Adjuster. The Wall Adjuster may be installed on the diffuser or on the wall and may be either wireless or wired to the diffuser.
Option 4: Therma-Fuser™ stand alone diffusers with Room Temperature Sensors and Wall Adjusters
A combination of Options 2 and 3, this option monitors room air temperatures and adjusts the setpoint with the BAS. The BAS can read an analog room temperature signal from a sensor installed in each diffuser and can read and reset the room temperature setpoint of each diffuser using analog signals from an Acutherm Wall Adjuster.
Option 5: Combination of Therma-Fuser™ stand alone diffusers with Therma-Fuser™ DDC interoperable diffusers
This option offers complete BAS digital input and output on selected diffusers and the simplicity of no wiring to the others. Key spaces are monitored and controlled by the BAS. Other spaces have the benefit of simplicity and low installation cost due to no diffuser wiring.
Option 6: Therma-Fuser™ DDC Interoperable diffusersThis option offers complete BAS digital input and output.
Each diffuser has the ability to supply room temperature, airflow and supply air temperature and receive signals for room temperature setpoint, minimum airflow setpoint, maximum airflow setpoint, override open, override closed, CO2 override and more. Digital signals can be either BACnet or LonWorks.
Take a look at the complete design guide: Acutherm BAS Design Guide
Have more questions, askRick?