This is an original factory Coleman sequencer (OEM). Heat sequencer consists of two even-height towers on one plate. 2 timings and 4 switches. The timings will come on (get hot) in 1-110 seconds (H1-110) and shut off (get cold) in 1-110 seconds (C1-110). The purpose of the timings is to turn on the heating elements in a sequence as to prevent a huge power surge which may blow a breaker. If your electric furnace isn't putting out enough heat, it may be that the switches in your old sequencer aren't closing. Or if it feels like an element is not shutting off, a switch in your old sequencer may be stuck closed. Same can be said about the blower motor. If the motor doesn't turn on or shut off, it may be an issue with the first switch (M1-M2). Be sure to doublecheck the wiring diagram of your furnace as some models use the sequencer differently. On a typical electric furnace, the blower motor is hooked to terminals M1 & M2 (perhaps referred to as H1 & H2 on other various sequencers). The heating elements are then hooked to M3-M4 and M5-M6 and M7-M8. 24V feeds the bottom (gold) terminals of the sequencer. Welded jumper bars connect the 24V from one tower to the next. If your application does not use these jumpers, simply twist them off with a pliers. Not all the terminals of the sequencer may be used in your application. In some cases, you may need extra terminals. If that happens, included are extra terminal adapters to convert one terminal to two. All our parts have a 1-year exchange warranty with us (no dealing with the manufacturer), so buy with confidence. We generally ship replacement parts the day you contact us. Replaces 3120-3571 Coleman 3400-3581 Coleman 3120-3381 Coleman 3120A357 Coleman 3120-3391 Coleman 3120A357 Coleman
