Learn How Air Handlers Work To Keep You Comfortable All Year

Air handlers, the unsung heroes of HVAC systems, play a crucial role in maintaining indoor air quality and temperature. Understanding how air handlers work is essential for homeowners, contractors, and anyone interested in the efficient operation of their heating and cooling systems. This comprehensive blog post will delve into the inner workings of air handlers, exploring their components, functions, and the principles behind their operation.

Components of an Air Handler

An air handler typically consists of the following components:

• Blower: The blower, also known as the fan, is responsible for circulating air throughout the ductwork.
• Coil: The coil, either an evaporator coil or a condenser coil, exchanges heat with the air passing through the air handler.
• Filter: The filter removes dust, allergens, and other particles from the air.
• Housing: The housing encloses the other components and provides a secure and insulated environment.
• Ductwork: The ductwork connects the air handler to the various rooms and spaces within the building, allowing for the distribution of conditioned air.

Functions of an Air Handler

The primary functions of an air handler are:

• Air Circulation: The blower circulates air throughout the ductwork, ensuring that every room and space within the building receives conditioned air.
• Heat Exchange: The coil exchanges heat with the air passing through the air handler. In cooling mode, the evaporator coil absorbs heat from the air, while in heating mode, the condenser coil releases heat into the air.
• Air Filtration: The filter removes dust, allergens, and other particles from the air, improving indoor air quality.

Principles of Operation

The operation of an air handler is based on the following principles:

• Refrigeration Cycle: In cooling mode, the air handler utilizes the refrigeration cycle to remove heat from the air. The refrigerant absorbs heat from the air as it passes through the evaporator coil, changing from a liquid to a gas. The compressor then compresses the refrigerant gas, increasing its temperature and pressure. The hot refrigerant gas then flows through the condenser coil, releasing heat to the outside air and changing back to a liquid.
• Heat Transfer: In heating mode, the air handler utilizes heat transfer to add heat to the air. Hot water or steam flows through the condenser coil, heating the air as it passes through. The heated air is then distributed throughout the building via the ductwork.

Types of Air Handlers

Air handlers are available in various types, including:

• Single-Zone Air Handlers: These air handlers are designed to condition a single zone or area within a building.
• Multi-Zone Air Handlers: These air handlers are capable of conditioning multiple zones or areas within a building, allowing for independent temperature control.
• Packaged Air Handlers: These air handlers combine an air handler, condenser, and evaporator coil into a single unit.

Factors Affecting Air Handler Performance

The performance of an air handler can be affected by several factors, including:

• Airflow Rate: The airflow rate refers to the volume of air circulated by the blower. A higher airflow rate ensures more thorough air distribution and temperature control.
• Coil Size: The size of the coil determines the amount of heat that can be exchanged. A larger coil can handle more heat load, resulting in more efficient cooling or heating.
• Filter Efficiency: The efficiency of the filter determines how effectively it removes particles from the air. A higher-efficiency filter will trap more particles, improving indoor air quality.

Troubleshooting Air Handler Issues

Common air handler issues include:

• Inadequate Airflow: This can be caused by a clogged filter, dirty coil, or faulty blower.
• Uneven Temperature Distribution: This can be caused by improper ductwork design or installation, or a malfunctioning zone damper.
• Poor Indoor Air Quality: This can be caused by a dirty filter or a lack of outdoor air intake.

What People Want to Know

1. What is the difference between an air handler and an HVAC system?

An air handler is a component of an HVAC system responsible for circulating and conditioning air. An HVAC system includes the air handler, condenser, and evaporator coil.

2. How often should I change the filter in my air handler?

The frequency of filter changes depends on the type of filter and the usage of the system. Generally, it is recommended to change the filter every 1-3 months.

3. What are the signs of a faulty air handler?

Signs of a faulty air handler include inadequate airflow, uneven temperature distribution, poor indoor air quality, and strange noises or vibrations.