Solar Thermal Closed-Loop (950-STCL) by Amatrol allows learners to develop the specialized skills and knowledge needed for working with the two common types of thermal closed-loop systems: drainback and pressurized. Solar Thermal Troubleshooting teaches learners about connecting, operating, programming, and troubleshooting both drainback and pressurized systems. The curriculum is presented in a highly-interactive, multimedia format that allows learners to use the learning style best for them: reading, listening, or visual. Solar Thermal Troubleshooting supports the NABCEP (North American Board of Certified Energy Practitioners) test for Certified Solar Thermal System Installer.