Browse Prior Art Database

Green Sigma Energy Wastage Alert : Air Handling Unit Cooling Valve Passing Disclosure Number: IPCOM000207893D
Publication Date: 2011-Jun-15
Document File: 3 page(s) / 47K

Publishing Venue

The Prior Art Database


Apply analytics to building control data to increase energy savings and reduce maintenance response.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 47% of the total text.

Page 01 of 3

Green Sigma Energy Wastage Alert : Air Handling Unit Cooling Valve Passing

Disclosed is a software application for identifying energy conservation opportunities and facilities maintenance issues as they occur in air handling units.

Within most buildings air conditioning is provided by Air Handling Units (AHU) that provide hot and cold air to the controlled environment by passing fan assisted air flow over heating/cooling coils (reference figure). The volume of heating and cooling energy provided to these coils is regulated through a series of control valves on the respective heating and cooling circuits, whose % open valve position is determined and commanded by the Building Management System control system.

In normal cooling function operation, these control valves modulate between 0% (closed - no cooling)) and 100% (fully open - maximum cooling). However mechanical degradation of these valves means that they may leak over time (not shut off completely) which can allow chilled water (waste energy) to pass through the valve undetected, and this over time would lead to considerable significant energy waste . Traditionally, valve testing and subsequent passing valve detection is performed as part of a regular preventative maintenance (PM) schedule conducted on a quarterly to a yearly basis. This PM is done by means of an onsite physical valve inspection and testing. Being able to detect valve passing real time, can reduce energy wastage and lead to significant resultant energy cost avoidance. Additionally testing of these valves is time consuming and costly, particularly for large and dispersed sites, where large numbers of these valves are in use.

Using computer analytics a system was established that allows for this passing valve condition to be detected in real time and report an energy waste alert to the user, through secondary means such as a maintenance work order or email. Application of this analytical system allows for significant energy saving through real time detection of the condition and the timely initiation of work order request to inspect and repair the valve, ahead of the scheduled PM, which could have allowed for up to 12 months of energy wastage to occur.

The software collects targeted data from the various sensors, and measurements present and used within the Building Management System (BMS). The points are currently used within the BMS to control the temperature of the operating environment (heating and cooling).

By automatically pulling periodic values for selected data objects, and applying appropriate formulas to this dataset, it is possible to generate alerts in real time notifying the building operator energy is being wasted because this alert condition criteria was achieved. In this scenario, an alert is generated when the formula, applied periodically identifies that the valve is passing/leaking energy. This is done by looking at the positive temperature difference observed across the valve indicating t...