10 Jul 2023

Smarter Control, Better Performance: Exploring Advanced Features of DX Units

DX  or direct expansion is the most commonly used air conditioning technology wherein the air is directly cooled at the boundary or directly adjacent to the space that you want to be conditioned.


In this system, the heat is directly exchanged with the refrigerant that passes through a local cooling coil. During the process, the refrigerant expands and an expansion valve is used to control it. This is also the reason why the term direct expansion is used to describe this process.


A DX unit is just another term for standard home air conditioners or commercial cooling solutions such as an HVAC system. These units include split systems, packaged air conditioners, ducted systems, and wall-mounted room air conditioners.


Features of a DX Unit


1. The Plant Room:

This room hosts various key parts of the DX system such as the compressor and the condenser. The compressor can either be an open type or semi-hermetically sealed. These semi-hermetically sealed compressors are cooled by a fan while the open ones are water-cooled.

The condenser is a shell and tube type which is cooled by water. The refrigerant moves along the tube and the water through the shell. This makes sure the refrigerant is cooled faster which ensures energy-efficient cooling.


2. The Air Handling Unit Room:

The air handling unit is kept in a separate room and the refrigerant after leaving the condenser enters the thermostatic valve and then finally reaches the air handling room.

An air handling unit consists of a cooling coil, a larger blower, and an air filter which are housed inside a large box. After leaving the expansion valve the refrigerant goes to the cooling coil.

The evaporator of a DX system  is coil-type and covered with fins. This gives a higher heat transfer efficiency from the refrigerant to the air. Two types of ducts flow out of this air handling unit.

One is for absorbing the hot air coming from the rooms while the other is for sending cooled air to the rooms that you want to be air-conditioned. The hot air that absorbs heat from the rooms is controlled by the blower, passed through the air filters, and then over the cooling coils.

The blower then passes this air through the ducts and delivers it to the rooms where air conditioning is needed.

3. Air-Conditioned Room:

This room can be a residential space, a hotel room, some part of your office, or a place where you store your IT equipment or other office machinery. The ducts that flow out of the air handling unit are connected to the diffusers or grills which are placed in the rooms you want to be cooled.

It is important to note that in DX units, you cannot keep the air handling units and the refrigerant piping at a very large distance from each other. If you do that then there will be a lot of drops in the pressure of the refrigerant which can make the cooling slower.

If the pipe is made to be extra long, more refrigerant will be needed which can lead to several issues like extra costs and higher leakage risks.

4. Smart Controls:

Most DX units can measure the temperature levels indoors precisely and use the most efficient operating mode to save energy. This helps reduce costs by preventing overcooling. These cooling solutions give you full control over the comfort level, temperature settings, and humidity levels, which gives you peace of mind.

5. Pumped Refrigeration Economization:

In DX units, the refrigerant pump can operate at nearly 1% of the power that is needed to operate a normal-sized compressor. This gives you a cooling power usage efficiency of about 1.05.

The compressor of a DX unit consumes about 50% to 70% of the total power needed to operate a DX unit. However, in recent systems, there is a pumped refrigerant technology that turns the compressor off when the outside temperature is low. 

The system goes into a cycle called the economization cycle where outdoor air is used to cool the refrigerant directly thus eliminating the need to use the compressor and the expansion valve.        


Performance Efficiency of DX Units

The heat transfer process in DX units is more advanced and sophisticated as there is no middle agency involved in the transfer of heat energy. Unlike traditional systems, the air is directly cooled by the refrigerant present in the cooling coil of the air handling unit which improves efficiency.

In DX units, the refrigerant has to travel through small distances which eliminates the need for a pumping source. This reduces the heat absorption even further which leads to higher efficiency.

Why DX Units are Worth It?

There are many benefits of installing a DX unit in your house or some commercial space. These units generate much less noise as compared to other cooling systems. The installation, maintenance, and operating costs of DX units are much lower than VTF, split AC, and certain HVAC systems.

DX units can regulate the humidity level of your space and deliver fresh air with very little to no contamination. Some advanced DX units give the freedom to cool a particular section of the building without affecting any other area.

These ac units are easy to adjust, they consume very little energy and you need very little room or floor space to install these. All these features of DX units make it worth your investment.

Final Thoughts

DX units are equipped with various advanced energy-saving and cooling features that give you the best indoor environment. If you choose this system, there will be no restriction as to where you can put the indoor and outdoor units. You can keep the length of the pipes as long as you require and there will be no visible difference in the cooling efficiency.

This cooling system offers you more flexibility in terms of installation and operation. So, if you are looking for an energy-efficient, cost-effective, and reliable cooling solution for your home or office, you can go with a DX unit without any worry.

Visit YORK MEA to explore our wide range of commercial-grade DX systems. 


by York
10 Jul 2023