These projects managed by Denis O’Connor during the last 25 years demonstrate the value of data (and the various ways it can be collected) to confirm equipment is installed and operated as intended.

US Navy Base - 85 Buildings

Existing Building Commissioning Project

The approval for a wireless network to collect BAS (Building Automation System) data is removed by the Navy during construction due to security concerns.  An abandoned pair of copper wires is discovered in the buildings and the Navy approves a recommendation to install 6 "dial up" modems.  Data is collected from controllers in individual buildings during the evening when facility maintenance people are not using the BAS systems.  Twice per month the data is transferred to the enterprise fault diagnosis software platform via an email attachment and a successful Existing Building Commissioning project is delivered to the Navy that addresses security concerns.

The data-driven Existing Building Commissioning identifies items that are not apparent from looking at the operator’s Building Automation System screens such as:

  1. Calibration problems with CO2, temperature, pressure and humidity sensors
  2. CO2 sensors improperly installed
  3. Problems switching from heating to cooling modes
  4. Outside air dampers that are not operating properly
The data-driven Ongoing Commissioning identified items such as schedule & setpoint changes, VFDs operated manually, and VFDs placed into bypass.    

Canadian Manufacturing Company

Waste Heat Recovery System - New Building Commissioning

A heat recovery system is installed to recover low-pressure process waste steam and heat the 100% make up air for the manufacturing plant.  Data is pushed from the process control system to the enterprise software once per day at the completion of construction.  Initial process control system data shows the projected amount of heat is not being recovered and the heat-recovery coil at the Air Handler is not installed as intended.  The data also indicates minor modifications to the control software will accommodate the as-built conditions, but the operators will need to make slight modifications to their daily routines.  
 
The data push to the enterprise software platform is increased to 4 times per day.  Daily review of heat recovery system KPIs (Key Performance Indicators) with the operators and weekly reviews with the Plant Manager turn this into a successful project.  With 80% of the project savings generated in Dec, Jan and Feb, timely access to data and the generation of actionable KPIs was required.

US Veterans Administration Hospital

Central Chiller Plant - Existing Building Commissioning

The BAS trend data indicated the 800 ton centrifugal chiller was not able to deliver more than 600 tons, which significantly reduced the available operating hours for the chiller.  The 1,000 ton steam-fired absorber was getting expensive to operate as gas prices rose from $0.30 to $1.38 per therm.  The following measurements were taken to determine if the chiller was getting the proper primary chilled water flow:
  1. Chilled water pressure drop readings across the chiller barrel
  2. kW readings at the primary chilled water pump
  3. Pressure drop readings across the primary chilled water pump
  4. “Shut-off Head" pressure head developed by the primary chilled water pump verified the pump impeller size.
Both sets of pressure drop readings across (1) the chiller barrel and (2) the primary chilled water pump indicated a primary chilled water flow rate consistent with the 600 tons trended by the Controlotron ultrasonic flow meter on the secondary loop.  The primary chilled water pump kW reading, pressure drop and shut-off head pressure confirmed the existing impeller size and indicated the pump casing & motor could support a larger impeller.
  
The order for a larger impeller resulted in a call from the pump manufacturer who stated the as-built information was not correct and the pump was originally shipped with a lower speed motor than the one ordered.  After reviewing the field measurements, the pump manufacturer recommended an impeller to support the required flow rate with the existing motor.   The centrifugal chiller delivered the rated 800 tons at a 10 degree F chilled water differential with the new impeller.  This resulted in a significant increase in the operating hours of the centrifugal chiller when it was more economical to operate than the steam-fired absorber @ $1.38/therm.

Canadian Manufacturing Company

Boiler Feedwater Economizer Installation - New Building Commissioning

A boiler feedwater economizer was installed in a large water tube boiler.  The economizer temperature profiles indicated the predicted savings were not being achieved due to incorrect heat exchanger piping connections.
 
When the trend data was forwarded to the design engineer, he immediately confirmed the heat exchanger was piped backwards and took responsibility for making the corrections.  This is a classic example of the importance of getting data as soon as possible during the construction process, because it is much easier to get items fixed when the contractors are still on site and final payments have not been made.

US Federal Campus

Hot Water Pump VSDs (Variable Speed Drives) - New Building Commissioning

Variable speed drives were installed on the secondary loop supplying hot water to a remote building of the campus. The new VSDs were saving more money than projected during the milder outside air temperature bins and it was observed that the hot water supply temperature was not being reset as much as would be expected. The hot water reset schedule was re-implemented in an effort to maximize the VFD savings without sacrificing boiler fuel.
  
The Victaulic coupling gaskets in the hot water piping system began to leak when the hot water supply temperature was reset below 180F. Unfortunately the piping system had been out of warranty for many years and a basic data-driven commissioning would have uncovered this issue during the piping system warranty period.