- The 24A34-3 White-Rodgers Electric Furnace Fan Heat Sequencer is used on many different electric furnaces to control and sequence the ON/OFF operation of the electric heaters.
- Sequencers are also used to turn the fan blower ON and OFF.
- There are several different types of sequencers. In the trade we refer to them as, “1 stack,” 2 stack,” “3 stack.” I would refer to the 24A34-3 as a “3 stack” sequencer.
- The following was written directly from the installation instruction book: The 24A34-3 White-Rodgers Electric Furnace Fan Heat Sequencer we sell are, “direct replacement units for sequencing both fan and heat. It can be used in a broad range of gas and electric heating equipment and many other applications where time delay is required. The sequencers we sell have a solid-state 24 volt heater, used to energize the control, and a variety of normally open contact sets. These contacts close and open within specified timings and are used to control the furnace fan and heating elements on demand from a room thermostat. These sequencers meet a wide variety of timing requirements and assures long life at high electrical loads as well as minimum radio and TV interference”.
- Each sequencer is stamped with timing specifications. For example, H1-20 C40-110 means the ON time for heating is 1 to 20 seconds and the OFF time for cooling is 40 to 110 seconds. The first contacts in the sequencer turn ON first and turn OFF last.