Final answer:
A receptacle must be installed in an attic with HVAC equipment, located within 25 feet of the HVAC equipment, as required by the National Electrical Code.
Step-by-step explanation:
The question pertains to the installation requirements for a receptacle related to HVAC equipment in an attic. The National Electrical Code (NEC) specifies that for safety and convenience, there must be at least one receptacle provided in the attic if it contains HVAC equipment. This receptacle should be located within 25 feet of the HVAC equipment to allow for easy maintenance and servicing. It's essential for such receptacles to be easily accessible and to have the necessary electrical protection, like GFCI (Ground-Fault Circuit-Interrupter), according to the NEC. This requirement ensures that technicians have the power supply needed to operate tools and test the HVAC system without the need for extension cords, which can pose a safety hazard.