Adaptive Intelligent Recovery - Honeywell LCBS Applications Manual

LCBS CONNECT SOLUTION
How do we do this?
Do I count folks as they come in and out of the controlled building space? There are a few promising technologies that
could "count people," but they simply aren't economical now. The preferred method to sense guest's presence in an
enclosed space is the detection of CO2 gas and associated sensing technology. Because this isn't a science lesson, we'll
be humane. Simply put, human beings breathe in oxygen and as our body processes oxygen and the other things we
consume, we "exhaust" and exhale CO2. CO2 is far from fatal if continually ingested by the human body, but it does make
us sleepy, grumpy, and less attentive. Again, not a science lesson, but we also refer to CO2 as a "trace gas." What is this?
Consider carbon dioxide and "proxy" for other nasty stuff in building environment. Simply put, there are other noxious by
products floating in the air including VOCs (outgassed from carpeting, paint, cleaning solutions) and bugs that float
around from folks coughing and sneezing. Just to be clear, when we refer to "cold and flu season," one of the contributing
factors of this phenomenon is bad building ventilation.
Providing good ventilation is important. Let's go back to the theory and operation of DCV. During building occupancy, we
continuously and dynamically sense CO2. If the level of CO2 is lower than our selected threshold, or "limit," we control rate
of ventilation at the "minimum ventilation damper position" level. Theoretically, this is a position that will provide fresh air
to estimated building occupant population as we've discussed before.
Let's add a factoid here. HVAC "scientists" suggest that at 800 PPM building CO2, bad things start happening to the
human being as we've shown. This becomes a typical and suggested setting to monitor and control carbon dioxide
content in our building space. Our automatic control system begins to reset minimum ventilation rates from our
"minimum ventilation damper position" level to our "minimum DCV ventilation damper position." This reset will
dynamically continue based on sensed carbon dioxide PPM level in the space.
Demand Controlled Ventilation Summary
LCBS Connect controllers can provide mitigation strategy based on the increase of CO2 as a "trace gas"
indicating the fouling of oxygenated air. As described, this results in "woozy" building occupants and can
also lead to illness as described in this document. As with previous control loops, there are many values that
you can alter that will make your DCV strategy work well or work badly. It is essential that you understand 1] what DCV
techniques you and your company likes to use and 2] what the prevailing building code, ventilation standard is for your
area.

ADAPTIVE INTELLIGENT RECOVERY

Adaptive Intelligent Recovery is a Honeywell is a patented feature that when properly applied 1] ensures comfort for
building occupants at occupancy even after equipment has been controlled at a higher (cooling) or lower (heating)
temperature after hours 2] gradually ramps set points up or down (heating or cooling) reducing wear and tear on
equipment and 3] reduces the likelihood of all equipment cycling at the same time that could result in undesirable high
electrical demand.
LCBS Connect controllers use Adaptive Intelligent Recovery to gradually and dynamically transition temperature
setpoints from unoccupied to occupied, standby to occupied, and unoccupied to standby operation. The concept of
Adaptive Intelligent Recovery is to gradually increase or decrease (heating, cooling) the set point from the unoccupied or
standby set point, to the standby or occupied set point over a period of time to match the recovery capability of the
mechanical system, providing benefits listed above.
31-00118EFS—01
DAMPER POSITION
MINIMUM DCV
VENTILATION
DAMPER
POSITION
MINIMUM
VENTILATION
DAMPER
POSITION
DCV
SETPOINT
Fig. 8.
18
SPACE CO2 LEVEL
DCV
SETPOINT
+ 100 PPM
MCR36702