Air Handling Unit Diagram

December 22, 2023 Post a Comment

Air handling unit diagram

AHU's supply fresh air to the room. The units take air from the outside, filter it and recondition it (cooled by a cooling coil or heated by a heating coil). Where hygienic needs for air quality are lower, the air from the rooms can be re-circulated for energy saving purposes.

What are the parts of an air handler unit?

An air handler is a metal casing containing two main components: An evaporator coil that circulates refrigerant from inside to outside to condition the air. A blower fan that moves the conditioned air throughout the home via ductwork.

Where does an air handling unit go?

They are usually located in the basement, on the roof or on the floors of a building. AHU's will serve a specified area or zone within a building such as the east side, or floors 1 – 10 or perhaps a single purpose such as just the buildings toilets. Therefore, it's very common to find multiple AHU's around a building.

What is AHU capacity?

The AHU 180 mobile air handling unit is versatile and is particularly suitable for outdoor installation, thanks to its aluminum housing. With a maximum air volume of 20,000 m³ and an external pressure of 491 Pascal, this air handler is perfect for ventilation and fresh air.

Why is AHU important?

An Air Handling Unit (AHU) is used to re-condition and circulate air as part of a heating, ventilating and air-conditioning system. The basic function of the AHU is to take in outside air, re-condition it and supply it as fresh air to a building.

What is the difference between AHU and HVAC?

AHU, which is Air Handling Unit is an appliance used to circulate air. HVAC is Heating, Ventilating and Air Conditioning system. HVAC is the central unit to which AHU is connected. AHU is only a part of HVAC and as such there is hardly any difference between then two.

How does AHU control humidity?

The AHU contains cooling and heating coils, humidification and the ability to dehumidify the air. It also contains the main supply fan which distributes air to the room terminal units. Supply air at the required temperature and humidity is distributed into the conditioned zone by room terminal units.

What is the difference between an air conditioner and an air handler?

Air handlers are designed to move air around. That's all that they do. They don't heat up or cool down, they move air. Air conditioners, on the other hand, exist only to cool air by removing heat from the outdoor air.

Is AHU connected to FCU?

This is a common question that can be easily confused since both involve the movement and cooling of air. An air handling unit (AHU) operates by bringing in fresh air from the outside, while a fan coil unit (FCU) generally recirculates and conditions the air in an interior space.

Is air handler inside or outside?

The air handler is the component that circulates air inside your home. It's typically found indoors, either in a closet or attic. An air handler's basic components are an air filter, a blower and a coil. The internal blower moves air through the evaporator coil and transfers it throughout the building via ductwork.

Can AHU work without chiller?

AHU's typically do not have their own cooling system built in, instead they will be connected to a central plant water or air cooled chiller, occasionally they will use some sort of split a/c unit and you can also find these connected to district cooling networks.

What is the CFM in AHU?

Cubic Feet Per Minute (CFM) is a measurement of airflow volume, determined by how many cubic feet of air pass by a stationary point in one minute. Larger homes circulate more air (since there's more space for it to move around), so they will have a higher CFM.

What is the formula for CFM?

This practical math formula goes a long way when you're considering air ventilation improvement in an indoor space: CFM = (fpm * area), where fpm is the feet per minute. To find the cubic feet per minute, substitute the FPM value with the area after the area is squared.

What is the temperature in AHU?

The supply air temperature is typically set at 55 F (13 °C) to control humidity in the space. However, dehumidification is not necessary when the outside air is dry. Meanwhile, the space may have less cooling load due to envelope heat loss and/or occupant schedule changes.

How many filters are used in AHU?

Inside an AHU we will typically find two sets of filters. The first set is known as the primary filters and we also then have the secondary filters. These both have different functions in an air handling unit.

Why heater is used in AHU?

As is the case with most AHU applications, controls are critical. Electric heaters provide constant heat when power is applied to the elements; therefore, a control panel is always supplied. Electric heaters in AHUs can be provided with three different types of control interfaces.

Which valve is used in AHU?

The AHU output is controlled using a control valve linked to temperature sensors in the system. As the energy output from the AHU is of a parabolic shape, an equal percentage (EQ%) control characteristic is provided by the control valve, which in turn will provide a linear response (see graph below).

Why AHU room needs fresh air?

Air handling units can be used to re-circulate a proportion of 'stale' air within a building, mixing this with fresh air to reduce the amount of air conditioning that is required. They can also include heat recovery, recovering heat from return air and using it to warm the supply air.

Is an AHU a heat pump?

The air handling unit features a reversible heat pump which can warm up or cool down the supply air stream using the extract air heat. The heat pump is equipped with an array of protection systems including low and high pressure protection, freeze protection (automatic defrosting) and compressor overheating protection.

What is AHU ducting?

An air handler, or air handling unit ( often abbreviated to AHU ), is a device used to regulate and circulate air as part of a heating, ventilating, and air-conditioning ( HVAC ) system.