In order to service and troubleshoot an air-source heat pump system, a service technician must understand the unit's sequence of operation. This is the order of events the system undergoes to cycle ...

[Glitch] got his hands on a slew of relays which are meant for use in industrial equipment. They are designed to operate at 24V. He wanted to use these with common microcontrollers and instead of ...

The fan center’s purpose is to control when the indoor fan turns on. Before the integrated gas control board, the indoor fan on gas and oil furnaces would either turn on at the same times as the heat ...

Have you ever needed to power a 12-volt relay in a circuit but only had 6 or 9 volts available? This simple circuit will solve that problem. It allows 12-volt relays to be operated from 6 or 9 volts, ...