AHU Unit

AHU Unit: The Complete Guide

Zonsteel only uses high quality copper tubing for the AHU unit, with high efficiency heat exchange beltline. The KKF central air double-intake centrifugal fan units used in AHU unit are quiet and efficient.

Zonsteel AHU unit design considered wind speed is less than 2.8m/s when air passes through the air cooler section. For heavy load you may need two coolers in parallel to ensure all air can be handled. Another factor must be considered in AHU unit design is a fan which must be equipped with proper shock-absorption, and rotate speed could not be too high. The filter must also have differential-pressure gauge and it also must be easily removable for maintenance purposes.

Zonsteel AHU unit also includes lights for maintenance purposes.

AHU unit is one part of whole clean room system, co-works with FFU units and air ducts to make air clean class 10 to 100,000. Zonsteel can help overall clean room engineering, especially complicated systems like chip factory, LCD panel factory, new energy (lithium battery and solar photovoltaic)

Zonsteel AHU unit is customizable, contact us today to get your unique AHU unit.

AHU Unit: The Ultimate FAQ Guide

The Air Handling Unit or AHU unit is an important part of your cleanroom to clean fresh air. It is essential for improving the air quality and make it better to use the cleanroom.

If you are here, then you want to learn more about AHU units that Zonsteel makes. That is something we will be discussing in this guide. The aim is to help you decide after getting all the information.

We have thought of the most common questions that people would ask about AHU units. Let us learn more below.

What is An AHU Unit?

Figure 1:  AHU Unit

An AHU unit is part of the air conditioning system in a cleanroom or any other room that needs one. The AHU unit works by combining both the purification and air conditioning applications into one unit.

Depending on the application, you can find several types of AHU units available in the market. We have several types of air handling unit at Zonsteel to offer to our clients.

We are always willing to help you learn more about the different types so that you can pick the right one for your needs, also know the air handling unit working principle.

We will also perform the installation for you even if you order from a different country. Yes, Zonsteel can do overseas installations.

What Is the Working Principle Behind AHU unit?

Figure 2: AHU Unit Working Principle

When the air gets to the AHU unit, it will be filtered, heated, and moisture-treated in the various components of the unit. This air is then transported to the upper part of the cleanroom by using a large air supply unit.

The air from the AHU unit will be sent throughout the cleanroom by passing it through a high-efficiency filter. We all know how important it is to maintain the cleanroom integrity.

The air is heated and moisture-treated too so that it can maintain the cleanroom needs in terms of temperature and humidity.

Since the air is also filtered, we expect it also to maintain the cleanroom cleanliness.

The air filtration is a continuous process so long as the cleanroom is operational.

The size of the whole AHU unit depends on your air supply and conditioning needs. Sometimes you can have several AHU units so that they can support the needs of your cleanroom.

What Are the Objectives of Setting up An AHU Unit?

Figure 3 Setting up AHU Unit

You might be new to air handling units or AHU unit, so you would want to know what are some of its objectives. Well, below are some of the reasons you would want to get yourself an AHU unit for the cleanroom.

1,    Good for fresh air intake to replace the polluted air in the cleanroom

2,     The AHU unit is good for air treatment through the process of filtration

3,     The AHU unit also controls the humidity and temperature of the air supply. This keeps it within the cleanroom needs.

4,      There will also be less noise production in the cleanroom. This is because you no longer need to open the windows.

5,     The AHU units are often easy to setup. Some are simply plug and play so setting them up should not take long.

What Are the Common Components of the AHU Unit?

Figure 4: AHU Unit Component

By understanding the different AHU unit components, you get a chance to learn more about how it works. You would also know how best to troubleshoot the AHU unit in case there is a problem. Here are some of the AHU unit components you should know about.

· Housing

Figure 5: AHU Unit Housing

The housing is simply the casing that houses the other components of the AHU unit. Inside you will find components such as the fan, filters, coil, and more.

The housing will mostly be made of sandwich panel, surface PPGI and insulation core is EPS, rock wool or PU foam. The cover for wall meet roof is aluminum, aluminum in terms of durability, anti-corrosion, and more.

The housing is designed in a way to have a drain pan to prevent cases of condensation. This is to further protect the internal components.

· Fan

This is often considered the very important of the AHU unit. Its centrifugal fan is necessary for pushing the hot or cool air to go through medium efficiency filter.

Depending on the type and application of the AHU unit, you can get different types of fans.

It is important that you ask more from the manufacturer about these different types of fans so that you get the right one for the job.

When choosing the fan type, consider its overall energy efficiency. You need to get a model with an impressive air-volume performance while at the same time using the energy efficiently.

· Heating and Cooling Coil

To make the unit complete, it will need to have the heating and cooling coil. This is where the AHU unit will heat or cool the air depending on the needs of the cleanroom.

Most of the time, the coil would be made of copper or aluminum.

You can always get in touch with Zonsteel to customize the AHU unit to meet your needs. Depending on the application, you might need more aluminum fins or copper tubes.

· Filters

The AHU unit filters are essential for keeping the dust to a designed level in the clean room. It is not just the dust but also other harmful particulate that should not be in the cleanroom.

The most common options as filters include medium and HEPA filters for AHU unit, sometime primary filter also be used.

· Humidifier

Humidifiers are also an important part of the AHU unit. They are mostly used in winter or cold-temperature areas where you have to set up a cleanroom. This is because the last thing you need is too much humidity in your cleanroom.

There are several types of humidifiers available. We will be able to help you learn more about them so that you can pick the right one.

· Mixing Box

The mixing box is another important component of the AHU unit.

It is used to mix the return air with the fresh air coming from the outside before resending the air into the heated or air-conditioned room.

The air that does not get mixed will be sent outside through the AHU unit exhaust.

What Are the Common Types Of AHU Units?

Figure 6: Types of AHU Unit

Here at Zonsteel, we make two types of AHU units for you to consider checking out. The two are;

✦  Combined clean air supply and air conditioning air supply systems

✦   Separated clean air supply and air conditioning air supply systems

We will look at them in detail below to help you learn more about them.

1. Combined Clean Air Supply and Air Conditioning Air Supply System

For this system, it can further be divided into four different systems. This includes the fresh air plan or DC system, primary return air plan, MAU + RAU plan, and primary and secondary return air plan.

The fresh air plan scheme is setup in cases where the clean room does not allow for the return of the air. This will be common in clean rooms of category A and B.

Also, if the clean room produces highly toxic substances, it will not need the return air to be in the room.

As for the one-time return system, it is common in clean rooms where there is a high production of heat and moisture.

Having the best air flow means that there can be a better elimination of the indoor waste of heat and humidity. The result is that you now have better breathability and humidity in the cleanroom.

The MAU and RAU programs will be common in various cleanrooms setup for various applications. This type of system will be good for monitoring and maintaining the cleanliness, humidity, and temperature of the cleanrooms.

This is achieved by having multiple circulating units in the cleanroom to eliminate as much indoor heat and humidity as possible.

2. Separated Clean Air Supply and Air Conditioning Air Supply Systems

You are likely to find this one also being referred to as semi-centralized air supply system. Under this system, the air conditioning air supply will be mostly used to eliminate the heat and humidity from the cleanroom.

This goes on to save a lot energy use to maintaining the air supply to the cleanroom.

The chances are you might have used the fan filter unit and the dry coil to solve the cleanroom temperature issues. However, these two use a lot of energy.

The solution is to separate the clean air supply system from the air conditioning air supply system. You will save a lot more energy.

Other than saving you on energy use, it also reduces the size of the air conditioning control room. Avoid to use the air duct, this means that you get your cleanroom higher indoor height.

For this system, it is further divided into three systems including;

✦  Air conditioning unit plus fan filter unit plan

✦  Fresh air unit plus circulating unit and fan filter unitplan

✦  Three air supply schemes including the fresh air unit, fan filter unit, and a dry cooling coil unit

Do not worry if the various types of AHU units seem confusing. Our technical team has experience in designing and manufacturing them. So, in case you have any issues, our team should be able to handle them. Also, if you have questions, they can make it all clear for you.

What Do You Consider When Choosing the Best AHU Unit?

Figure 7: Best AHU Unit

· The Cleanroom Needs

This is the most important consideration that you have to make about the AHU unit. Take the time to list down your cleanroom needs before you can buy the AHU unit.

It is the cleanroom needs that will dictate the type of AHU unit that you buy.

Zonsteel manufacturers different types of AHU units. So, it is important if we can tailor it to the cleanroom type too.

Even if it is another manufacturer, the AHU units are designed to work for specific cleanrooms, so it is good to know what you need.

· Application Area

AHU units do not have to work for the cleanroom alone. The same can be used even for office building or hospital. It is then important that you know where you would want to install the AHU unit before choosing one.

The AHU unit for the office building would have different levels of maintenance, installation needs, and functionalities from the one installed in a hospital.

Once you know the application area of the AHU unit, then you can get the right one for the application.

· AHU Unit Capacity

You can never ignore to consider the expected capacity of the AHU unit.

This is because it would determine if it would be efficient in filtering, heating, or cooling the air for your area of application.

There are times when you might have to use more than one AHU unit to adequately handle your air purification and supply needs.

If you are not sure where to begin, then talk to us for more advice on how to proceed with sizing the AHU unit correctly.

· The Installation Process

Figure 8: AHU Unit Installation

Another thing you have to consider is the installation needs of the AHU unit. It should be easy and smooth enough for you to get the AHU unit setup correctly.

The last thing a person needs is to deal with additional costs when it comes to installing the AHU unit.

Always talk to the manufacturer to understand the installation needs of their AHU unit before settling for one that would be easy to setup.

Zonsteel AHU unit could be flat pack shipped, and install on site. This way save a lot on freight cost and installation manual will be provided after shipping.

· Maintenance Needs

Just like any other machine, the AHU unit would also need maintenance. The maintenance is crucial to keep the air handling unit working properly just as you need.

Take the time to check out what other people say about the operation of the unit. It gives you a general sense of the maintenance needs of the AHU units.

The unit that you choose should not have too much maintenance needs that it becomes an issue when it is used more often. And you can easy access as each part has separate door.

What Are the Maintenance Checklist Ideas for An AHU Unit?

Figure 9: AHU Unit Maintenance

The functionality of your HVAC system is dependent on how good you take care of your AHU unit. It is why we had to highlight some of the maintenance tips that you would want to keep in mind when handling an AHU unit.

✦    You need to check your air dampers more often. The air dampers need to be opening, closing, and modulating correctly. The maintenance team will have to test the damper movement to ensure they are working properly. There might be some adjustments that have to be done to fine tune the AHU unit.

✦     Still as part maintenance, you need to look at the heating and cooling coils of the unit. The same goes for the valves. If the valves fail, then the system might start to unnecessarily heat and cool at the same time. This can cause discomfort in the cleanroom where the unit is supposed to handle the air circulation better. The coils also need the right cleaning to leave them working correctly.

✦     The checklist also includes the status of the filters in the AHU unit. Monitoring of the static pressure can help you know when it is time to change the air filters. The unclean air filters can waste a lot of the facility’s energy as the AHU unit needs to work harder to push the air through the filters. You need to change the air filters as soon as they get blocked. High efficiency filter is usually changedevery 6-12 months.

✦        Check to see if the sensors are working correctly. This includes the temperature sensors, humidity sensors and more. If they are not working correctly, then they might lead to a few issues when it comes to the working of the AHU unit.

What Is the Cleaning Process for An AHU Unit?

Figure 10: AHU Unit Cleaning

Cleaning the AHU unit is important to ensure that it works properly. Below, we will discuss some ideas on how to get your AHU unit cleaned correctly.

✦    Before you can start cleaning the AHU unit, shut it down first. You need to turn off the power at the source to avoid the possibility of ending up with an electrocution. You can now proceed to disconnect the AHUunit drain lines. When this is done, remove the fans and coils from their positions for further cleaning.

✦     At this point, you can start to clean the coils, casing, and fans separately. Remove as much dust and dirt from the air handler unit casing. Using mop to clean the coils, fan, and casing.

✦    It is still a good idea to use household bleach to clean the drain lines even further. The bleach will also reduce the chances of new clogs coming up.

Once everything has been cleaned, what follows is to assemble the parts together again. Make sure to follow the steps correctly of setting up the various components in their correct position.

Why Is My Air Handling Unit Sweating? Causes and Possible Solutions

Figure 11: AHU Unit Working Principle

The AHU unit sweating could be several things. As a result, it is best if you know what is the cause and how to resolve it.

Below, we will look at some of the possible causes and their possible solutions to consider.

✦       Having improper or no insulation of your ducts. Without proper insulation, then condensation or sweating would appear on the metal surface. So, if that is the issue, then you need to get your AHU unit ducts with the right insulation to avoid condensation.

Figure 12: AHU Unit, Air Handling Unit

    ✦          There are times your AHU unit might be installed in a crawl space. If that is the case, proper sealing is important so that the humid outside air does not lead to the sweating problem. Once the crawl space is properly sealed, then you will notice that the sweating problem is reduced or eliminated.

Figure 13 : AHU Unit, Air Handling Unit

    ✦           Depending on your location, there are times you might be in an area with too much relative humidity. It is then great if you would install a dehumidifier in such an area to reduce the sweating problem.

Figure 14: AHU Unit, Air Handling Unit

    ✦           If you have choked filters or blocked ducts, you end up with a restricted airflow to the different parts of the building. This means that you also end up with high chances of sweating of the AHUunit. Since the air flow is restricted, then the air temperature would go below its dew point and thus leading to sweating. Consider changing the filters more often so that the AHU unit can work efficiently.

Figure 15: AHU Unit, Air Handling Unit

    ✦           The temperature setting could also be an issue sometimes. For each of the relative humidity you might be operating in, there is a temperature where condensation can start to happen. Consider this temperature and adjust the temperature of the AHU unit to clear condensation.

Conclusion

From the guide above, it is easy to see that Zonsteel would be the best manufacturer for you in terms of AHU units. The brand has with a wide range of AHU units so that you can get the right one for the job. You will also like the fact that you can get them at an affordable rate, this air handling unit price is very competitive.

With years of experience, we make some of the best AHU units in the market. Our models are durable, versatile, easy to setup, and more.

We are always open to give you a tour of our facility to help you learn more about the AHU units and their applications.

If this is something that you like, then talk to us today for more information on AHU units. Our team will have all your inquiries and give you the best rate depending on your AHU unit requirements.