Mike Eardley, PE, LEED AP, CCP Director of Commissioning CannonDesign Brian Berg, Jr., PE, LEED AP, CSI Principal Berg Engineering Consultants, Ltd. April, 2014 The Power of Retro-Commissioning Illinois Healthy & High Performing Schools Symposium

Commissioning (Cx) Definition Cx Process Cx Applied to Existing Buildings Retro-Commissioning Examples Human Factor in Buildings Hot/Cold and Energy Concerns Q&A Agenda

High Performance Buildings Characteristics Functionality Energy Efficiency Indoor Environmental Quality Comfort Sustainability (ability to perform its function in a long term)

Building Systems Commissioning Buildings function as intended Realize high system performance Promotes integration of systems Document facility requirements

Commissioning (Cx) is a comprehensive and systematic process to verify and document that new or renovated facility systems function completely as designed to meet the owner’s requirements Retro-Commissioning (RCx) is the commissioning of a building that has never been commissioned. Energy goals and low/no-cost measures often a focus Commissioning Definition

Without Commissioning Placement and calibration of Sensors Simultaneous Heating and Cooling Incorrect function of air-side Economizer and other efficiency measures Operating Schedule is not what is necessary, or assumed by energy model Cycling daylighting and other systems

Energy Impacts -Large effort in sustainable and energy efficient design -Will not be realized if design or intended use is:  misunderstood  ignored -Or if building systems are:  operating incorrectly  not thoroughly tested

Purpose of Functional Testing -Verification of an operational system  not a trouble shooting exercise (in theory) -Reduces adjustment and tuning during occupancy -Impacts  energy  comfort  maintenance  functionality

Types of Functional Testing -Building Automation System -False load -Seasonal testing -Trend analysis

Commissioning: Process applied to new construction or major building renovation Re-commissioning: Facility has previously been commissioned and is in need of a “tune-up” Retro-commissioning: Performed on facilities that have been in service and never commissioned Ongoing commissioning: Ongoing program of structured commissioning throughout the lifetime of a building New and Existing Buildings

Definition: Commissioning a building that never has been In practice: re-tuning systems Or, identify low-cost / no-cost measures to implement Site survey, owner interview, trending Drawings study, engineering calculation Retro-Commissioning Process

Energy measure identification Implementation Measurement & Verification Persistence SEDAC Retro-Commissioning Program ComEd Retro-Commissioning Program Retro-Commissioning Process

Trending -Functional testing before occupancy is a snapshot -Trending shows operation over time -Methods of trending  building automation system  portable data loggers -Analyze trends  spreadsheet calculations  software tools

Ongoing Commissioning -Good  Cx process with functional testing -Better  Re-Cx program -Best  Ongoing Cx -Combination of software, engineering support, action

Document current operation Identify opportunities for improvement Evaluate payback, consider measures Implement measures Verify measures LEED for Existing Buildings

Typical Air Handling Unit

Typical Air Handling Unit – Components

economizer variable air volume hot water heating chilled water cooling Moving Parts

Common Problems – Air-side Economizer -Damper is stuck / broken / non-functional -Control algorithms fighting  heating during economizer  mechanical cooling when free cooling available -Outside sensor calibration or location

static pressure reset supply air temperature reset hot water reset chilled water reset demand control ventilation zone level CO 2 control Controls

morning warm-up occupied / unoccupied Scheduling