How to read the source list
Each guide lists the sources supporting its most important factual statements. We favor official agencies, licensing authorities, public programs, standards, and manufacturer instructions appropriate to the exact context.
The scope note explains what a source can support and where it stops. For a provider, property, vehicle, patient, or facility decision, verify the current record directly.
Current source pack
- Homeowner HVAC and refrigerant FAQsU.S. Environmental Protection Agency
Refrigerant and technician requirements; no homeowner refrigerant work.
- Purchasing and repairing home air conditioners and heat pumpsU.S. Environmental Protection Agency
Repair/replacement and refrigerant context.
- Heating and cooling maintenance checklistENERGY STAR
Maintenance context and professional service boundaries.