Blowers

A blower is a tool for cleaning dust, debris, and other particulate matter from air intakes of an air conditioning or refrigeration system. The term also refers to the act of moving (blowing) these materials away from the air intake. Blowers are often used in dusty industrial environments where filters can become clogged with debris and need to be cleaned on a regular basis. They can also be used as an alternative to wet vacuuming in places where water isn't readily available for cleaning such as food service establishments, restaurants and hospitals.

Blowers are commonly powered by electric motors or compressed-air engines. Blowers come in many different sizes, power levels, and air delivery rates (CFM).

Outside food service establishments and other commercial locations, blowers are used to keep the outdoor HVAC equipment free of dust and debris. 

Indoor blowers are commonly mounted on or near the air handler or air distribution unit. In larger unitary systems, a dedicated blower cabinet is used to house the blower. In small systems, the blower is either mounted directly on top of the air handler or in a duct that draws from directly above it.

Blowers are used in air conditioning and refrigeration systems to condition the air in the commercial or residential building. Blowers are used with - and, in fact, may be integral parts of - packaged terminal air conditioning (RTAC) units. In this application, the blower will be inside a cabinet similar to an HVAC unit but much smaller, often called a "surge" box. This is typically located on or near the air handler unit, especially in commercial applications where delivered air may have to travel over long distances before reaching end users such as offices or apartments. The blower motor can also be located inside the room itself several feet from the edge of the ceiling or ductwork where it draws from.

A blower is designed to handle particles larger than 1/16" (1.6 mm). Much smaller particles still have to be filtered, so be sure to clean the filters on your unit. A blower is more effective when it is able to travel in a straight line, so make sure the ductwork has enough room and angle for the air handler. 

There are many different types of blowers, some with variable power operation (i.e., variable speed), some without and some that combine the two. Blowers can be powered by both electric motors or compressed air engines. The power requirements of the blower depend on its size and CFM (cubic feet per minute). For duct work, consider a blower that has a variable speed control.

Blowers are generally used in indoor environments in industrial or commercial settings, where it may be difficult to find access to water for cleaning. Food service establishments such as restaurants, fast food outlets and grocery stores often use blowers to clear the ductwork and hoods for routine maintenance. Hospitals use them for removal of particulate matter from the air flow during patient care procedures. The main purpose of an air ventilation unit is the removal of dust from incoming air so that adequate air flow can be provided throughout an environment . 

The current trend in the commercial HVAC industry is toward using blowers for residential applications. Residential blowers are often used for clean air delivery to homes (as opposed to heating/cooling). The most common use of a blower in a residential application is for whole house air purification. Other uses include dust and debris removal from venting systems.

There are four common types of blower power sources: Electric motors, exhaust fans, electric-driven fan, and compressed-air engine. Each type has its own advantages and disadvantages. Electric motors are quiet but can be expensive and can require specially certified technicians to maintain them. Some electric motors may need to be replaced periodically due to burnt-out brushes. Exhaust fans are more efficient than blowers and will remove the most dust particles, but they are louder than blowers. Exhaust fans must have an exhaust dampener to minimize noise and typically run all the time. Electric-driven fan (EDF) units are more expensive than blowers, but they tend to perform better in dusty environments because they operate at a lower level of air flow which produces less contamination. Air conditioning and refrigeration systems can use AEDs (blower-engine driven) for air intake for both heating or cooling as well as in duct work for ventilation . Compressed-air blowers operate at lower pressure and are often used in plumbing applications such as sewer cleaning. 

Blowers are commonly powered by electric motors or compressed-air engines; blowers can also be powered by their respective exhaust fans. Blower motors usually provide variable speed control, and some systems offer variable speed or electronic controls. Blower motors generally use an electric motor for power with varying speeds of operation as well as an exhaust fan to provide the air movement. Blower motor shaft contactors and/or bushing kits may be necessary to connect the motor to the airflow distributing ductwork (e.g., a metal duct that carries air from the supply registers to the various rooms in a building). The need for the blower motor contactors and bushing kits is based on the size of the blower, the pressure of the airflow (i.e., CFM), and other variables. 

The power requirements of a blower depend on its size and CFM (cubic feet per minute). Generally, compressed air engines have lower power requirements, but they are noisy and require special maintenance. Electric motors are more efficient than compressed-air engines in terms of energy consumption, but they can be noisy. Electric motors also require lubrication and special care when operating in dusty environments. Blowers can use electric motors, compressed-air engines or exhaust fans to provide power. 

The compressor unit is best suited to provide the energy required by a blower, while the motor unit is used to drive the blower. Blowers can be turbocharged (i.e., "accelerated" or "boosted") with a booster compressor that amplifies air flow into the blower. The biggest benefit of this type of system is saving energy and reducing noise. This can be accomplished by increasing compressor capacity by mounting a second unit in parallel with the first as shown in figure 2 . 

Blowers are commonly installed in commercial, industrial and residential applications, but their application outside of these industries is expanding rapidly. The applications for which air handling units are integral parts of the systems (e.g. cooling, heating, dehumidification and air purification) are constantly evolving. One emerging market is the use of blowers in energy efficient homes. The blower serves as a dual purpose unit capable of recirculating air to keep fresh air from leaving the building while removing dust from supply air .

The primary purpose of an air ventilation unit is to remove dust from incoming air so that adequate air flow can be provided throughout an environment . Air ventilation units can be installed for a number of purposes, such as whole house fan systems that pull in outside air through open windows/doors and distribute it through the house via registers.

Conclusion

• Blowers are a common feature in heating, ventilation and air conditioning (HVAC) systems.

• Blowers are generally used for air delivery to homes (as opposed to heating/cooling). The most common use of a blower in a residential application is for whole house air purification. Other uses include dust and debris removal from venting systems, and duct cleaning.

• Varying the speed of an exhaust fan as well as the amount of airflow can effectively clear debris from ducts in order to ensure clean air flow throughout the home.