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How to control Temperature and Humidity in Air Handling Unit






 

How to control Temperature and Humidity in Air Handling Unit

Overview

Air Handling unit is a system used to supply temperature and Humidity controlled filtered air to the cleanroom. For air filtration various types of filters are used in AHU. And for temperature and Humidity controlling cooling and heating coils are provided in AHU.

Goals

  1. Control the temperature of air used in the cleanroom 

  2. Control the humidity of air used in cleanroom 

  3. Air filters

Specifications

   The air Handling unit consists of

  1. Air filter 

  2. Cooling coil

  3. Heating coil

  4. Air blower

  5. HEPA Filter 

Controlling of Temperature and Humidity 

  1. By Cooling Method 

The cooling coil recirculates the chilled water having temperatures between 4°C to 6°C. This chilled water comes from the Chiller through centrifugal pumps.

When we start the Air Handling unit blowers sucks the air through the pre filters of the air Handling unit. When blowers sucks air, it passes through the cooling coils. The temperature of the cooling coil is near about 6°C to 8°C. When the air passes through the cooling coil,heat exchange happens between the air and chilled water. Due to the chilled water the temperature of air is decreased and Humidity present in the air is condensed on the fins of the coil. Now as per the temperature and Humidity requirements in the cleanroom, you can do the chilled water supply and return adjustment for maintaining required temperature. But due to chilled water temperatures are very low because that air temperature also decreases lower than its limit, at that time you can control the temperature of air  by applying the hot water in the heating coil. 

  1. Humidity Control by heating Coil 

Some time in summer days or if chilled water temperature is not properly maintained, in this situation some time air temperature is at its lower limit but Humidity is out of limit. So if you increase the chilled water supply then your Humidity will be controlled but the temperature also decreases than its lower limit. So because of that you can not increase chilled water for controlling Humidity. 

In this situation you can use hot water to control the air Humidity.  If you apply some amount of hot water in a heating coil then your Humidity will be controlled in its limit and temperature also can be maintained upto its higher limit.





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Comments

  1. UnknownSeptember 27, 2020 at 10:31 PM

    Thank you for this valuable information. Welcome to Arctic Mount

    ReplyDelete
  2. A Best Air TulsaJanuary 25, 2023 at 6:07 AM

    Thank you soo much for sharing this useful blog with us. Contact our company to find Heating problems and if you are looking for air conditioner repair tulsa

    ReplyDelete

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