What is the maximum distance a duct heater can be installed from a heat pump or air conditioner without additional labeling?

The correct answer is based on the guidelines established in electrical standards and installation practices for HVAC systems. A duct heater can generally be installed up to 4 feet away from the heat pump or air conditioning unit without the need for additional labeling. This specification ensures that the installation maintains safety and efficiency, as well as compliance with electrical codes and local regulations.

Distance requirements like this are in place to prevent potential issues such as inadequate heat transfer or electrical concerns that could arise from longer runs without proper marking or specifications. If the installation exceeds this distance, additional labeling is typically required to provide clarity on the system's operation and safety features, ensuring that future maintenance and inspections can be performed effectively.