Massachusetts HEAT Loan Participating Lender. The Mass Save® HEAT Loan Program offers customers the opportunity to apply for a 0% loan for the installation of qualified energy efficient improvements in their homes. To qualify for a loan, the customer must own a one-to-four family residence and obtain a Home Energy Assessment though the Mass Save Home Energy Service program. When the application and proposals are received, Mass Save loan administrator will perform an Eligibility Review, and issue a HEAT Loan Authorization Form. Customers will NOT be able to apply for a loan with a Participating Lender before obtaining a HEAT Loan Authorization Form. (This prohibition does not include obtaining pre-qualification from a participating lender.) Service area: Haverhill, Merrimac, Amesbury, West Newbury & Groveland