The position of the glycol loop coils in the AHU
is shown in Figure 6.
The details can be provided as a label that allows the AHU
manufacturer to "check off" the lamp system installed.
The global AHU
market is highly fragmented with the presence of several vendors.
The fifth state point of air is when the air travels to the central AHU
where it is conditioned with a DX AHU
In some instances, replacing the components may not be sufficient to achieve the required performance but an AHU
refurbishment can also include the replacement of whole sections, or addition of new sections to supplement what's already there.
Since the system flow rate is determined by the terminal unit controllers through the actions of terminal dampers and the AHU
system, efficiency is not directly controllable; minimizing the duct static pressure setpoint is the primary strategy to minimize AHU
Energy modeling indicates that if the AHUs
had been 100% outdoor air supply systems with 50% effective airto-air heat recovery, the amount of heating energy at the AHU
heating coils would have roughly doubled to about 4% for this building.
supplies a trunk duct and terminal units reheat the air as needed.
Added conduction losses from the AHU
and adjacent ductwork reduce system efficiency.
Based on the proposed plug-and-play framework for an air-handling unit (AHU
) and technology gap analysis in Part I of this work (Zhou and Nelson 2011), a critical step that is needed and has yet to be developed is a way to automatically resolve control system ambiguity, specifically, identifying AHU
control system inputs and outputs, including their logical or physical locations.
Both the OA AHU
2) and the exhaust AHU
3) are located in a mechanical room on the ground floor on the north side of the building.
Nevertheless, only limited experimental studies under restrictive scopes were available to evaluate AHU
automated fault detection and diagnosis methods (Norford et al.