Steel: Lifeline of the HVAC Industry

Heating Ventilation and Air Conditioning equipment move air between outdoor and indoor spaces to perform the function of heating and cooling. This process is termed ventilation. 

HVAC is a complex assembly of systems working together seamlessly to provide thermal comfort for the occupants accompanied by indoor air quality. All kinds of buildings are required to have HVAC systems to: -

• Add or transfer heat from the air inside a building

• Control the humidity

• Filter the air

For all these requirements, HVAC piping systems use hot, chilled and condensate water, condensate drainage, steam, refrigerant and gas to deliver from the HVAC system through a network of pipes. 

The cooling system comprises chilled and condensate water, wherein the chilled water system pumps water in a closed loop. Heat is absorbed and passed on at three stops in the chilled water system.

The first stop is the fan coil unit which is located all throughout the building.

The next is the chiller, which uses a refrigerator to cool the chilled water; the last one is the condensate water system, which exposes the water to the cooling tower atmosphere. The heating system adds up the steam and hot water systems and uses a boiler to produce the steam using fuel oil or natural gas. Boiler pressure forces the steam through the piping to a heat exchanger. The heat is transferred into hot water inside the heat exchanger and is carried to the occupied space. Condensate water is collected through steam traps after the steam has exhaled the heat. It is then allowed to condensate back to a liquid state. 

The third stop is the hot water system. This system derives its heat from the heat exchanger and is pumped into the building spaces where heat is required. 

These heating and cooling networks of pipes are collectively called HVAC systems.

Types of HVAC piping systems

There are two types of HVAC piping systems – central plant equipment piping and delivery piping. The main plant equipment room has a network of pipes connected to the rotating tanks and equipment. They are connected to different equipment like heat pumps and exchangers over the pump room, from where the pipes transfer the process liquid to other parts of the building through delivery piping.

HVAC Piping material

Most of the HVAC system components are made of metals. The most commonly used metals in HVAC systems are Steel and copper. While copper is used for smaller piping and is very expensive, Steel, on the other hand, is not just cheaper but is also a commonly used material for large sizes. Unlike copper, Steel can also combat higher pressure and is a perfect choice for hot and cold water. 

Following are the types of steel applications in the HVAC system: -

Black Steel ASTM A53 / A135 – These light wall black steel pipes are used for chilled and heating water services of 8 inches and above

Black Steel Pipes ASTM A120 and A53 – Schedule 40 black steel pipes are used for services like chilled and hot water piping, miscellaneous drains, chemical treatments, steam vent and emergency generator exhaust.

Galvanised Steel Pipes ASTM A120 – Schedule 40 galvanised pipes are used for miscellaneous indirect wastewater pipes

Type 304 or Type 306 Stainless Steel – Stainless Steel is used in pipework and boilers because of its higher resistance to moisture and corrosion, especially when it comes to the air we breathe; it is vital to avoid the accumulation of harmful mould.

Mild Steel is commonly used for pipework and other HVAC constituents like pumps.

Factors to consider before selecting HVAC material

Corrosion – Corrosion is the biggest concern of any HVAC manufacturer. It can be caused by acidic gases, increased temperature and humidity. Environmental understanding is essential in material selection. 

Coating options – When a coating is applied in coil form before manufacturing, it is called continuous coil coating. This process forms a protective layer between the coil and the environmental conditions. A thinner coating enables better heat transfer. Generally, there are four types of coatings – polyester, epoxy, hybrids and anti-microbial. You can select coating basis your requirements. The polyester coating has good physical properties, durability and flexibility. Epoxy will give you a hard, metallic, non-toxic finish. The hybrid coating can be used if you are looking at anti-corrosive coatings for metallic substrates. Lastly, the anti-microbial coating is a good option if you are looking at lower maintenance and easy-to-clean coating.

At JSW One MSME, we have a diverse inventory of steel grades and finishes to meet all your needs regarding the manufacturing of HVAC equipment. Our dedicated support team ensures that all your orders are processed quickly and efficiently.

Contact us today for all your HVAC steel requirements.