What is an HVAC Sequencer?

By Ezmeralda Lee

An HVAC sequencer is a small circuit designed to help stabilize circuits and turn switches on and off quickly in an electrical setting. The sequencers are designed to stage the different parts of the electrical equipment so that the appliance does not over load and break the circuits. Many products use the HVAC sequencers to keep engines and other mechanical devices from overheating or exploding.


An HVAC sequencer is identified by its unique size and shape. Depending on the size of the final product, the sequencers can be different sizes as well. There are usually two different segments to a HVAC sequencer, and they are attached together by a smaller middle piece. They are constructed of tough metal, and are usually heavy. HVAC sequencer can be used in things such as: electric pumps, furnaces and motors.


Each type of HVAC sequencer has its own set of features. Some of the most common features, however, are shared among many different kinds of HVAC sequencers. Some common features are: the ability to have a few seconds delay between sequences, several different mounting positions, the ability to resist shocks and vibrations, and a 24-volt input control. HVAC sequencers are designed for several different kinds of tasks, which makes them have versatility in the features that they offer.


The purpose of HVAC sequencers is to provide different electrical and gas powered mechanical devices that run continuously with a way to keep cool enough to always be on. The sequencers allow the pumps or furnaces to use a portion of the power in segments so that there is always one part of the device on, and other parts off. This helps keep circuits from blowing out, or motors from overheating, causing the whole mechanics to have to be replaced. Sequencers can also help facilitate the process of the mechanical devices which helps the machine run more smoothly.


There are many different benefits to using a HVAC sequencer. The main benefit is the ability to save power on different pieces of equipment. The sequencer allows the equipment to run off of less power. HVAC sequencers also prevent loss of equipment due to power shortages and circuit breaks. The sequencer spaces out the power so that the engines and other delicate equipment parts do not get over heated. This saves the owner of the equipment both time and money.


Most equipment that requires the use of a HVAC sequencer comes with one pre-installed. However, it could become necessary to replace the sequencers at some point in the life of the equipment. It is best to study closely what kind of sequencer would be best for the equipment at hand. It is important that the sequencers in a piece of equipment are always running properly. Without them equipment can quickly over heat and break. It is much more expensive to replace the entire machine than it is to replace the sequencer. Keeping the sequencer in good working condition will save a lot of time and money.

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