DIY HPWH Installation & Maintenance Study

This project will assess pathways, technical solutions and guidance for simplified DIY homeowner or general contractor replacement of existing electric and gas water heaters with new heat pump water heaters (HPWH) in California. Permitting and code requirements for water heater installations can place significant limits on what residential homeowners can legally perform in water heater replacements, but the introduction of new plug-in 120V unitary and split HPWH products are designed to reduce the complexity of installations. Identifying the necessary plumbing, mechanical and electrical requirements and potential technical or process solutions to simplify and expedite permitting and installation could conceivably make DIY (or alternatively, general or HVAC contractor installations) more prevalent. The project team will engage existing programs offering rebates accessible to non-professional installers to evaluate opportunities to provide additional resources and guidance for quality HPWH installations, including a public facing DIY digital fact sheet/guide that will be available should California IOUs and CCAs want to share with their customers. The guide will identify the most important considerations for homeowners regarding the technical and permitting process to install their own HPWH, including supporting customers through DIY install feasibility while directing to relevant rebate and incentive programs. The project team will interview homeowners and general contractors that have completed recent HPWH installations to capture their reasoning, access to rebates and installation instructional guidance, and overall approach and experience. The project will also document recommended maintenance procedures for homeowners to support continuous high efficiency operation and product longevity. Our research intends to validate the size of the market that might be interested and able to take advantage of DIY installations, understand the necessary equipment and skill sets and provide actionable recommendations to program administrators on how to best support this alternative residential HPWH replacement path.