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Meet Our Instructors

Tim Abshire

Tim Abshire, Residential Heat Pump Water Heating

Tim is a Senior Account Manager and Certified Trainer for D+R International. Most recently he managed the Wholesale Distribution channel and was responsible for implementing Northwest Energy Efficiency Alliance’s (NEEA) Hot Water Solutions Program through the wholesale and installer supply chain. Hot Water Solutions is a market transformation effort designed to promote the replacement of standard efficiency electric water heaters to heat pump water heaters. Tim provides education, training, and resources to both plumbing and HVAC regional distributors along with their installer trade networks. His background, including utility management and wholesale distribution, provides him with extensive knowledge and understanding of distribution operational needs and requirements. Tim is a State Certified Heat Pump Water Heater Continuing Education Instructor in Oregon and Washington and has conducted over 250 training courses to distributor branch and installer personnel.

Nick Brown

Nick Brown, Energy Modeling & Analysis

Nick is a Certified Energy Analyst (CEA) for residential and an Associate Energy Analyst (AEA) for nonresidential construction by the California Association of Building Energy Consultants (CABEC), and has maintained his certifications for 2008, 2013, and 2016 code cycles. He is a subject matter expert on the Energy Code Ace statewide education team and teaches classes for Southern California Edison on net zero design, all-electric homes, and selling clean energy homes. As part of a CalSEED team, Nick is currently researching phase change material applications in HVAC systems. Nick was elected to the Board of Directors of CABEC beginning in 2018. He has written and presented extensively on net zero buildings, high-performance walls, and energy efficient building.

Evan Green

Evan Green, Commercial Heat Pump Water Heating

Evan is a research engineer with Ecotope, Inc., where he investigates ways to best measure and optimize CHPWH systems and consults with manufacturers to effectively bring new CHPWH products to the market.  He is also involved in working with governing bodies and laboratories to help inform codes and standards involving CHPWHs across the country.  Prior to his work with Ecotope, Inc., Evan previously served as Applications Engineer at Colmac WaterHeat, where he consulted with plumbing engineers on the best ways to implement HPWHs into their designs, in addition to performing equipment startups and evaluations of completed domestic hot water systems. Evan graduated from Eastern Washington University with a B.S. in Mechanical Engineering.

Colin Grist, Commercial Heat Pump Water Heating

Colin primarily specializes in heat pump water heating systems. He has designed and commissioned over a dozen successful systems from multiple vendors. He performs building analysis, load calculations, energy modeling, and HVAC engineering design using tools such as AutoCAD, Revit, and eQUEST. On site, Colin works closely with clients on commissioning, construction administration, and energy audits of new and existing buildings. Colin leads the central heat pump water heating engineering team at Ecotope. He is a Professional Engineer, WA, and holds a B.S. in Mechanical Engineering from University of St. Thomas.

Bobby Hahn

Bobby Hahn, HVAC Installation and Sales

Bobby is a principal at Pacific System Group with 28 years in the HVACR Industry. His experience includes VRF, Ductless, DX Systems, Chilled Water, Air Quality, Filtration and Controls. Bobby is a member of the CABEC, IHACI, ASHRAE, ACCA, MANNA and was a past board member of the Institute of Heating and Air Conditioning Industry.

Thomasena Philen

Thomasena Philen, HVAC-R

Thomasena has worked in the HVAC-R industry since 1986 as a licensed technician, contractor, instructor, curriculum designer, and consultant. Thomasena has designed and taught HVAC-R courses for Daikin North America, Trane, Eastfield College, and ATI Enterprises Technical Training Center, among others.  She holds an Associate of Science in Residential Air Conditioning from Eastfield Community College and a B.S. in Adult Education and Instructional Design from Texas A&M University in Commerce. She received the HVAC Excellence Dedication to Education award in 2017.

Michele Sagehorn

Michele Sagehorn, Building Systems Optimization

Michele Sagehorn is co-founder and principal at Red Car Analytics, a high-performance building consulting company. She provides expertise on how to use real building data combined with user experience and feedback to deliver energy and comfort and make building systems perform optimally and pragmatically. Her projects span building design and construction for large campuses, building owners, and energy utilities companies. Michele is LEED AP certified and holds a B.S. in Aerospace Engineering from University of Michigan.

Lester Terrance

Lester Terrance, HVAC

Lester Terrance has been active in the HVAC industry since 2003, including 12 years in the United State Air Force, seven of those years serving as HVAC Field Supervisor at the US Department of State. He is a licensed Master HVAC in the states of Maryland and Virginia, an EPA Certified Universal Technician, and an Authorized Overseas Certified Technician (Multistack). Lester holds an AAS in Mechanical and Electrical Technology and is an HVAC Instructor and subject matter expert at D+R LEARN.

D+R LEARN’s building systems curriculum includes more than 40 instructor-led and online, on-demand courses led by these expert instructors.