top of page
  • lowyh93

What are air handling unit access doors in HVAC?

Updated: Jan 3

air handling unit access doors

An Air Handling Unit, AHU in short, is an item of machinery that is being implemented commonly in both commercial and industrial environments to regulate and condition interior air flow.

It does this by efficiently moving air through a system of indoor and outdoor air ducts and filters, utilizing both heat and moisture transfer through heat exchangers.

air handling unit access doors blueprint

In the structure of an Air-Handling Unit (AHU), it consists of basic components such as dampers, pre-filters, final filters, heat exchanger (Heating and cooling coil), blower, filter frames, and access doors.

Several functions of an AHU can be defined as below:-

  1. Obtain air from the outdoors and clean and condition it       

  2. Heat or cool the air as needed for the HVAC system.          

  3. Acts as a chamber to  push the air through the ductwork inside the rooms of the building

  4. Manage and ventilate the interior with outside air.

To understand further on the Air-Handling Unit (AHU), you may read through the article in the link attached:-

Air-Handling Units Access Doors

As time goes by, the AHU is widely used at any buildings to control temperature, ventilation and air movement. It comes with the access doors in order to provide additional security, ergonomic in design and energy efficient.

An air handling unit with access doors is a necessary piece of equipment in commercial and industrial environments. It helps regulate humidity, temperature, and airflow inside the building and can be customized according to the needs of the space.

As the presence of access doors in AHU allow a technician to swiftly access and inspect the interior components of the appliance during maintenance, access doors simplify the maintenance tasks.

Advantages of Air-Handling Units’ Access Doors

With the installation of access doors to the AHU in commercial or residential structures, it possesses advantages as below:-

1. Optimum Indoor Air Regulation

The presence of access doors on the air-handling unit allows the humidity level to be sustained. Indirectly, this may assist with allergies and improve indoor air quality.

For those countries which are experiencing 4 seasons, the access doors are pretty useful in warming up the interior climate during the winter or vice versa in the summer. It provides a steady indoor environment.

An AHU is designed to keep the interior atmosphere steady regardless of the outside weather.

Humidity level can be stabilized to prevent either being excessively high or low, aiding in the maintaining comfortable temperature upon keeping within a tolerable range with AHUs.

2. Indoor Air Quality Improvement

Air quality could be enhanced with the access doors available by removing impurities inside the ducting such as dust, pollen, and odours which directly impact a bad interior environment.

On most occasions, the animals or insects can also get inside the ductwork in the absence of access doors through internal or external holes. Numerous diseases can result from the waste and general harm caused by animals.

When duct access doors are absent, an environment that is conducive to the growth of mold and bacteria is created inside the duct affecting the indoor air quality deteriorated and in more serious cases, the humans who live with such conditioned indoor air will get into illness due to the air quality breathed in are not in good shape.

3. Convenient Maintenance Tasks

Accessing the ductwork system also requires duct access doors. It is impossible to properly clean the air conditioning ducts without the right access doors.

The duct system is frequently difficult to access because it runs along the walls and ceilings of the building.

Dust and debris will accumulate in these difficult to reach places. It is feasible to access the duct system and guarantee a thoroughly cleaned ventilation system with the right access doors.

In such a case where the AHU’s ductwork is hidden and highly unreachable, it makes the maintenance work for technicians during periodic maintenance more convenient with the presence of access doors at the appropriate location of the ducting.

Rest assured, the system will be much more efficient with regular inspections and proper preventive maintenance carried out.

4. System Efficiency and Effectiveness Improvement

Access doors' air handling units have several benefits for both the environment and architectural design. Summer cooling and winter heating are made possible by the systems' ability to maintain consistent temperatures and to provide customized temperatures.

Compared to mechanical systems, which only offer temperature-dependent controls, this is far more efficient. AHUs can be configured to use less energy, reducing the building's carbon footprint and power costs.

Besides that, air leaks from the building can be minimized with the integration of AHU system access doors into a wider building automation system, which directly assists in managing the environment and cost optimization.


In short, the presence of access doors in an AHU brings tremendous advantages which are directly beneficial to the consumers from the aspect of air quality, cost, efficiency and effectiveness.

TCW Group, as a one stop HVAC manufacturer based in Malaysia able to provide advice and services onto any designs of AHU which inclusive of access doors which are made up of PU panels.

TCW Group is able to manufacture several types of access doors such as access doors with panel locks or with hinges. For any inquiries, please do not hesitate to reach us at

Access Door with Panel Locks

185 views0 comments


bottom of page