The 4 Construction Sectors and Their HVAC Requirements

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The construction sectors include public and private projects

Need to know more about the different construction sectors? Knowing the 4 major construction sectors, how they differ, and the required ventilation systems will help you better understand the construction field.

elearning-training.com gathered defining information about the 4 sectors of construction and how air conditioning and heating differ in each sector.

Sectors of Construction

Construction plans and projects can be commissioned publicly, by municipal agencies, or privately. Projects like bridges, highways, pipelines, residential structures, or facilities like hospitals and stadiums fall under one of the four construction sectors. To better understand the various types of project classifications in the construction industry, consider the following:

1. The Residential Construction Sector

The construction sectors include residential projects

Residential construction is building, remodeling, repairing, building (ground up), or modifying the structure’s interior or exterior. Residential construction refers to buildings meant to “house” people, equipment, or supplies.

Typically, those new to the construction industry assume residential construction refers only to homes and buildings for people. However, a residential building can also include garages and utility sheds. This construction sector also addresses installing electricity and wiring, plumbing, sewage systems, and pavement.

Residential HVAC: HVAC (heating, ventilation, and air conditioning) systems are responsible for heating and cooling your home and can include:

Note: A residential HVAC unit is much smaller compared to a commercial or industrial HVAC system as it needs to cool or heat a much smaller, more confined space.

2. The Institutional and Commercial Construction Sector

The construction sectors include institutional and commercial projects

This crucial construction category includes the following:

  • Schools
  • Medical Facilities (hospitals, testing centers, etc.)
  • Sports Arenas and Stadiums
  • Prisons
  • Retail Stores
  • Shopping Centers
  • Skyscrapers

This construction type includes the building, maintenance, and eventual or potential upgrades and modifications. Typically, institutional and commercial buildings in service for decades may be commissioned for upgrades and modernizations. This is still part of the institutional and commercial construction sector.

Work in this sector may be commissioned by private companies, public entities, local or state governments, and private investors. However, projects, including schools, medical facilities, and sports arenas, are often planned, managed, and paid for by a mixture of government and private or public entities.

Institutional and Commercial HVAC: Institutional and commercial buildings used by the public (schools, airports, hospitals, prisons, recreation centers, etc.) bring unique HVAC challenges since each construction comes with specific ventilation, cooling, and heating requirements. This often demands manufacturers and contractors to develop specific solutions, inventing new parts and equipment when needed.

3. The Specialized Industrial Construction Sector

The construction sectors include specialized industrial

This construction sector typically involves highly-specialized and technologically more advanced structures than the typical residential, commercial, or institutional construction. Projects classified as specialized industrial construction may include building structures that deal with:

  • Chemical Production
  • Medical (infectious diseases, virus research, biological testing, etc.)
  • Power Generation (oil refineries, nuclear plants, steel mills, etc.)
  • Tech
  • Aerospace

Funding and executing these project types typically falls to the industry or field seeking the building or structure and may lean heavily on for-profit companies, investment firms, and corporations.

Specialized Industrial HVAC: These HVAC systems are highly challenged to ensure the correct operation of equipment and machinery that must operate in specific environmental conditions (certain industrial processes, like welding, produces considerable heat that must be disposed of, while other processes may produce harmful, airborne substances which must be contained).

4. The Infrastructure and Heavy Construction Sector

The construction sectors include infrastructure and heavy projects

Heavy and infrastructure construction includes adding roads, railways, or communication towers to areas surrounding existing structures. Infrastructure and heavy construction are typically done to serve public interest/needs and are mostly funded by private corporations and governmental agencies. Some of these construction projects may include:

  • Highways
  • Tunnels
  • Transit Systems
  • Aviation
  • Bridges and Overpasses
  • Pipelines and Waste Management
  • Telecommunications

Infrastructure construction includes the stations and support facilities that operate transit centers and serve the general public.

Note: This type of construction is typically executed from spring through late fall. During the winter months, other projects are undertaken until springtime, when this construction work resumes.

Infrastructure and Heavy Construction HVAC: Buildings in this construction sector are typically heated through an assortment of heat pumps using air or water. Cooling systems (chillers with air-handling equipment) can be two-pipe or four-pipe and must keep large areas with many people properly ventilated and conditioned.

The Major Construction Sectors

In this article, you discovered essential information about the 4 sectors of construction and each sector’s HVAC needs.

Knowing more about the different construction sectors will help you better comprehend your construction work and how heating, air conditioning, and ventilation requirements can vary.

Not knowing how the construction sectors differ can leave you unprepared when your expertise, input, and suggestions may be needed.

Sources:
digital.library.unt.edu/ark:/67531/metadc40151/m1/1/high_res_d/R41806_2011May03.pdf
esc.edu/media/academic-affairs/harry-vanarsdale/hvacls-publications/Construction-Industry-Fact-Book.pdf
goconstruct.org/why-choose-construction/what-is-construction/
intechopen.com/chapters/62059
wbdg.org/resources/high-performance-hvac

What is an HVAC Pressure Test?

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Residential and commercial hvac units should be pressure tested often

Keep leaking ductwork from driving up your heating and cooling bills. Understanding what an HVAC pressure test is and how one can help you detect and correct leakage issues will help your heating and cooling system operate more efficiently.

elearning-training.com gathered the following information about HVAC pressure tests, what they indicate and when you should have one performed.

What is an HVAC Pressure Test

Residential and commercial structures can suffer from duct leakage. In fact, duct leakage can take as much as 25% of the energy from a heating and cooling system. This is when the ductwork in a structure is no longer air-tight, allowing airflow to escape from the pipes. Duct pressure testing measures the amount of leakage in a duct system and air handler.

What Causes HVAC Duct Leaks?

An HVAC pressure test, duct pressure test, or duct leakage test checks that the ducts are properly sealed. Ducts can leak from any of the following:

  • When a structure suffers a significant jolt from a falling tree
  • Partial or total roof failure
  • Earthquake
  • Age or corrosion
  • System vibrations
  • New ductwork was installed
  • Construction or repair work disturbed ductwork, breaking its seals

It is crucial to seal your HVAC ductwork and test it. Detecting and fixing leaks can significantly improve equipment efficiency and occupant comfort.

Note: Typically, the only time duct testing is required (in new or adversely affected construction) is when HVAC system components are installed or run outside the conditioned area.

What Kind of HVAC Pressure Tests are There

There are several metrics used to determine your duct system’s condition. Two of them are:

  1. Technicians can test for Air Flow in cubic feet per minute (CFM). This determines the system’s soundness in maintaining consistent pressure and airflow.
  2. Leakage area estimates can help you figure out and visualize the potential and total amount of leaks in your system.

With these methods in place, a technician can attach calibrated fans to multiple locations in the system to introduce air and locate leaks within or outside the building.

Note: This testing method is similar to how a plumber tests pipes using water pressure; professional HVAC technicians use air or inert gas to test a duct system’s pressure.

Are All Pressure Tests Conducted with Air?

Pressure testing for smaller units is typically done with dry nitrogen or other inert gas. Air is sometimes used on larger systems, particularly ammonia systems, when moisture concerns are not as substantial.

HVAC Duct Pressure Test Cost

A duct leakage test can cost anywhere from $200 to $600, depending on the licensed company performing the test and how many systems or ducts your structure has. A duct pressure test will help you identify any inefficiencies, correct them, and save you money over time.

Tip: Collect estimates from at least 3 professional/licensed HCAV installation and service companies.

IECC Requirements for Duct Leakage Testing

Residential and commercial hvac units can cause increased utility bills with leaking ducts

The International Energy Conservation Code (IECC) is a model code regulating minimum energy conservation requirements for new buildings. IECC verification can occur via either a post-construction or rough-in test.

Post-Construction Test – The post-Construction test involves sealing up all the registers in the structure, hooking up a calibrated fan, and pressurizing the duct system to 25 Pascals (Pa). The post-construction test, leakage measurement must be made across the entire system, including the manufacturer’s air handler enclosure.

Rough-In Test – For a rough-in test, all register boots should be taped or sealed. Leakage measurement is made across the system, with the manufacturer’s air handler enclosure if it is installed. If the air handler is not installed at the time of the test, total leakage is required to be less than or equal to 4 cfm per 100 feet squared of conditioned floor area. This test is also conducted at a pressure of 25 Pascals.

Note: The IECC serves as a “go-to” resource for states adopting an energy code. An International Code Council (ICC) code is in use or adopted in all 50 US states. Every three years, the ICC goes through the updating process for the building codes outlined in the IECC. Updates were recently codified in 2021 and will be updated in 2024 and again in 2027.

HVAC Duct Pressure Test

In this article, you discovered what an HVAC pressure test is, when you should have one performed, and what this test indicates.

HVAC duct pressure tests help you identify leaks in your heating and cooling system’s ductwork so you can fix them and avoid being surprised with outrageous utility bills.

Ignoring the need for an HVAC pressure test will leave you with high heating and cooling bills, inefficient conditioned air delivery, and extra stress on your HVAC to keep your structure heated or cooled.

Sources:
energycodes.gov/technical-assistance/faqs/what-are-requirements-duct-leakage-testing
epa.gov/sites/default/files/documents/RealZeroGuidetoGoodLeakTesting.pdf
basc.pnnl.gov/resource-guides/total-duct-leakage-tests#edit-group-compliance

How Long Does an HVAC System Last

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HVAC units last longer when regular maintenance is performed

Don’t miss the opportunity to extend your HVAC system life and prevent losing valuable business because your HVAC unit stopped working. Understanding how long HVAC units last will help you get it replaced while it is still an option.

elearning-training.com gathered information about an HVAC’s lifespan, how you can help it last longer, what maintenance should be done, and what signals that it’s time to replace the unit.

How Long Will My HVAC Unit Last?

Most Heating, Ventilation, and Air Conditioning (HVAC) systems are built to last from 15 to 25 years, but depending on the type of system and other contributing factors, estimated lifespans may vary.

How to Prolong Your HVAC’s Lifespan

Your HVAC unit is already built to last for decades. However, you can keep it running efficiently and extend its lifespan by:

  • Installing, upgrading, or reinforcing your building’s insulation
  • Check your structure’s weather stripping and seals
  • Periodically checking on your condenser’s performance
  • Leaving the unit’s settings on “AUTO”
  • Upgrading to smart thermostats throughout your building
  • Regularly change the system’s filters
  • Schedule biannual HVAC maintenance visits
  • Encourage using fans and space heaters to lighten the load on your HVAC unit

Note: The operational health and efficiency of your HVAC will almost always depend on whether or not you properly maintained it throughout its lifetime.

HVAC Maintenance

HVAC units function properly for longer periods when regularly serviced

Whether your HVAC technician is inspecting your unit for the summer or winter season, routine maintenance typically includes:

  • Thorough cleaning (coils, drains, internal elements, etc.)
  • Testing safety controls
  • Monitoring refrigerant pressure
  • Testing heating elements and exhaust system(s)
  • Lubricating all moving parts
  • Inspecting and repairing connections, thermostat function, and motor operation

Note: HVAC tune-ups provide a valuable service to property owners and managers. They can restore a unit’s lost efficiency and capacity, and tune-ups significantly improve reliability by detecting problems before they lead to system failures.

HVAC Repair and Replacement

Your HVAC unit will likely operate for years without calling much attention to itself. However, when things go awry, and malfunctions begin occurring, immediate attention should be given to getting it repaired or replaced. The following are signs that your unit has reached or surpassed its life expectancy:

  • Your air conditioning is blowing warm air
  • Little to no air is blowing out of your vents
  • The thermostat has stopped working
  • Your unit is making loud noises
  • Water or gas leaks increase around the unit
  • Your electric bill skyrockets
  • Pilot light Problems have become commonplace
  • The unit has reached its projected lifespan

Humidity – One of the principal functions of an HVAC unit is significantly reducing the amount of humidity inside your structure. Even when located in a low humidity climate, the ambient air maintains small amounts of moisture. If you detect humidity within your building while the air conditioning component is running, the unit may need immediate repair.

Bad Odors – If you detect a moldy odor from your HVAC unit, chances are likely that mold or mildew has begun growing in or around your HVAC unit. This is commonplace since the air conditioning components remove excess moisture (humidity) from your structure in addition to cooling it. When condensed moisture cannot drain, mold and mildew grow quickly in areas retaining that moisture.

Electrical Malfunctions – There are multiple electrical components controlling your HVAC unit, including:

  • Circuit boards
  • Power wires
  • Fans
  • Compressors

If your HVAC emits a smell like burning gunpowder or plastic, it likely means any one, or a combination of these components are burning. In this situation, immediately shut down your HVAC unit and consult your professional HVAC technician for emergency repair or replacement.

Gas Leaks – The most alarming of these signs is the smell of gas leaking from your HVAC system. Natural gas itself has no smell, but utilities and gas companies mix it with methyl mercaptan to give it a distinctive odor. This odor ensures immediate detection and helps prevent fires, explosions, and severe harm from inhalation when gas leaks. In this case, your first action should be to shut off the gas flow, shut down your HVAC unit, ventilate your building, and call your gas provider to locate and repair the source of the problem.

Note: Malfunctions and maintenance emergencies often occur during severe weather and temperature. This is when your HVAC system is pushed beyond its capabilities. A properly working HVAC unit is crucial to a building’s occupant’s comfort and health.

HVAC Lifespan

In this article, you discovered how long HVAC systems last, how you can extend their lifespan, what maintenance is required, and signs that it’s time to replace your unit.

By keeping up with your HVAC unit, its maintenance program, and watching for signs of its decline, you can keep your building’s air consistently conditioned for decades.

Ignoring your HVAC unit and its needs can result in angry tenants, loss in revenue, and costly repairs.

Sources:
rsi.edu/blog/hvacr/troubleshooting-basic-hvac-problems/
coynecollege.edu/common-hvac-airflow-issues-how-to-fix-them/
florida-academy.edu/5-common-hvac-issues/
epa.gov/indoor-air-quality-iaq/should-you-have-air-ducts-your-home-cleaned

Central Air Conditioning How it Works

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Central air outside units

Avoid the costly mistake of having the wrong air conditioning unit installed in your home. Knowing how different systems work will help you make informed decisions and save money when the time comes to install or replace your air conditioner.

elearning-training.com gathered information about central air conditioning components, how it works, types of air conditioners.

What Is a Central Air Conditioning Unit

An air conditioning system, more commonly referred to as a “split-system air conditioning system” or simply “central air,” is typically comprised of the following components:

  • An analog or digital thermostat that regulates the system’s operation
  • A fan, condenser coil, and compressor housed in an outdoor unit
  • An indoor unit located in the attic, basement, or centrally located space, housing a fan and the evaporator coil (this component circulates cooled air)
  • Insulated copper tubing guiding the refrigerant flow between the indoor and outdoor units
  • An expansion valve regulating refrigerant flow to the evaporator coil
  • Ductwork from the indoor unit, guiding or circulating cooled air throughout the space and back to the unit

The same components and principles comprising a residential air conditioning system are found, on a larger scale, in industrial/commercial units.

How a Central Air Conditioner Works

When you turn your thermostat down, machinery whirrs up and cools down the air. Right? Let’s better answer what happens when you turn your thermostat down:

  1. The thermostat is adjusted to regulate the amount of cool air to be distributed
  2. The compressor (outside) pumps refrigerant between the condenser coils (outside) and the evaporator cooling coils (inside) to cool indoor air
  3. Evaporator cooling coils remove heat and humidity from the air
  4. A fan or blower moves air over the cooling coils and disperses it through the ductwork
  5. A fan blows air over the condenser coils (outside) to release/dissipate the collected heat
  6. As ambient air is cycled back into the system, it passes through a filter(s) to remove particles and other impurities.

Note: The quality of air filter(s) used with your air conditioning system can significantly influence ambient air while keeping dust and impurities out of your system. Get an HVAC Inspection if you suspect a problem with air quality, impurities, or circulation.

Air Conditioner Types

Depending on your geographic location, how you prefer your air-conditioned, and the size or configuration of that space, there are three primary types of systems. Consider how the following air conditioning systems work:

Packaged Air Conditioner – This system, more common in the south and southwest of the country, contains the condensing coil, evaporator coil, blower fan, and compressor all in one unit. Packaged air conditioning units are ideal when there isn’t enough interior space for a split system or where rooftop installations are desired.

Like other systems, packaged air conditioning units remove warm air from the structure via return air ducts, forces it over evaporator coils, then returns that cooler air back to the structure through supply ducts. In the same manner as other systems, undesired heat is released outside by way of the condenser coil.

Split-System Air Conditioner – These systems are the most common air conditioning solutions. They contain an outdoor unit (compressor, condenser coil, and fan) and an indoor unit (evaporator coil, blower, and filter).

Split-systems can support varied (fan/cooling) speeds, allowing for single, two-stage, and multi-stage systems. Split-system air conditioning provides consistent, economical, and reliable temperature control throughout the entire structure.

Note: Two-stage and multi-stage air conditioning systems are more common in larger, renovated, and newer structures. They are often found in areas with severe cold or hot weather. These units will have a setting or switch presenting “low, medium, and/or high” options.

Ductless Air Conditioner – These systems are ideal for structures built without ductwork. Their installation is less invasive than other systems and can deliver chilled air to targeted areas within the structure. The indoor unit (blower fan and evaporator coil) connects to the outdoor unit (compressor, condenser coil, and fan) via copper tubing, which carries the unit’s refrigerant.

Central Air ductless unit

Installation of the indoor unit can occur on the ceiling, a wall, or the floor. With some systems, multiple indoor units can be connected to a single outdoor unit. Regardless of the number of indoor units, the operation of a ductless system is remarkably similar to that of a split-system.

Note: Today’s air conditioning systems operate on the same principles Willis Carrier applied when he invented the first modern air conditioner in 1902.

How Central AC Systems Work

In this article, you discovered essential information about air conditioning components and configurations, how these systems work, and types of air conditioning units.

Knowing how air conditioning systems work allows you to select the most efficient and economical system for your home or business.

Not knowing how AC units can be configured and installed can leave you with a structure riddled with uneven and uncomfortable air conditioning and costly utility bills, as your system will always have to overcompensate to meet your desired temperature.

Sources:
energy.gov/energysaver/central-air-conditioning
vistacollege.edu/blog/careers/trade/heating-ventilation-air-conditioning-terminology-need-know/
douglas.k-state.edu/docs/homeandfamily/library/Select_Home_Cooling_System.pdf
sites.austincc.edu/hart/resources/how-does-air-conditioning-work/

5 Common HVAC Problems and Solutions

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HVAC units often malfunction due to neglect or a lack of regular maintenance visits

Prevent your HVAC unit from failing and potentially damaging your roof when extreme weather and temperatures settle in for the season. Knowing how to spot trouble with your HVAC unit and get it taken care of will help you save money and prevent more severe problems in the future.

elearning-training.com gathered information about 5 common HVAC problems, the inconveniences they can cause, and how to solve them before they cause expensive damages to the unit or the structure it’s meant to regulate.

What are the most common HVAC problems?

Your heating, ventilation, and air conditioning (HVAC) unit uses various technologies to control the temperature, humidity, and air purity in an enclosed space. The ultimate goal is to provide continuous thermal comfort and reasonable indoor air quality.

There are multiple reasons your HVAC system may stop functioning properly, and here are 5 of the potential reasons, the damage they can cause, and how to get them fixed:

1. Dirty Filters

HVAC units often malfunction or develop severe problems due to dirty air filters

Dirty air filters are one of the most common and repetitive issues affecting your HVAC’s performance. A dirty filter is also one of the most straightforward problems to fix. Your air filter(s) should be changed regularly. Replacement intervals will depend on your local air quality, whether you have pets, if you smoke, or even how/what you cook. You may need to change your filters every month.

At the most basic function, air filters remove impurities like dust, pet dander, or (higher grade filters) bacteria from the air that flows through the system. This improves the air quality within your home and protects your HVAC system from damage.

Solution: Maintain a schedule that reminds you at a set interval to inspect or replace your HVAC system’s air filters.

Tip: For those suffering from allergies or may have a compromised immune system, HEPA filters are designed to remove a minimum of 99.97 percent of particles in the air 0.3 microns or larger. This title is endorsed by the Energy Department. While most commonly used in commercial settings requiring ­extremely clean air, like hospitals and laboratories, they can be used in residential structures.

2. Clogged Drain Pipes and Water Leaks

Air conditioners and high-efficiency furnaces tend to produce condensate. Drain pipes are used to encourage proper and consistent water drainage. However, furnaces can leak water if the drain lines are either clogged or develop cracks. In residential structures, this problem can be avoided by helping keep the drain lines clean by pouring bleach down the drain periodically.

Other potential leak sources may be the collector box, heat exchanger, or drain pan. A professional service technician should be contacted to determine the source of the water leak and repair options.

Note: Water leaks can go on for weeks, months, or years depending on their location and how frequently your HVAC unit is serviced. According to atlantacommercialroofingcontractors.com, these leaks can result in costly structural damage to your home (when the HVAC unit is installed on your rooftop, this problem can lead to roofing system failure).

Solution: Have your HVAC unit thoroughly inspected at least once per year by a professional, licensed technician.

3. Lack of Maintenance

One of the more common causes of HVAC problems and mechanical failure is disregarding regular system maintenance. Regularly scheduled maintenance by a professional, licensed service contractor is necessary to keep your system in top working order.

Many typical furnace or system repairs can be avoided with regular maintenance by a certified professional service contractor. Home heating and cooling systems are typically expensive investments. Why not protect that investment?

If you neglect to perform regular maintenance, you will most likely experience unexpected and costly structural damages, increased energy cost, and poor unit performance, or complete breakdown.

Solution: Scheduling regular HVAC unit inspections will help you stave off or permanently avoid expensive HVAC repairs or replacements.

4. Thermostat Problems

HVAC units often malfunction due to aging or poorly programed thermostats

Thermostat technology has changed how we interact with our heating and cooling, and even when controlling your HVAC unit on-site or remotely. Smart, programmable HVAC thermostats can help you economize on energy costs while maintaining a more comfortable environment.

Programming the correct thermostat settings for your home may take some time and effort on your part. Whichever thermostat you settle on for your home, read the instruction manual to ensure that you’re getting the most out of its features and capabilities.

Even the best or most sophisticated thermostats can malfunction. If you’re having difficulties maintaining specific temperatures in your home, a maintenance inspection may identify thermostat sensor problems or other developing problems.

Solution: Know the capabilities of your thermostat and how to use them to your advantage. When you encounter a glitch, don’t hesitate to get a professional involved to guide you through it.

5. Pilot or Ignition Issues

Ignition problems can result from several malfunctions. A dirty pilot, change in airflow, obstructed flame sensor, or clogged burners can cause a pilot outage, furnace lockout, or delayed burner ignition.

This problem could also result from a gas supply problem or wear and tear of an ignition component. When pilot and ignition issues arise, it is best to have them seen and handled by a trained service technician familiar with the dangers and required protocols for handling natural gas and high voltage.

Solution: Your HVAC’s pilot system, gas connection, and exhaust should all be regularly inspected and serviced to avoid potential gas poisoning or explosions.

What Can Go Wrong With HVAC?

In this article, you discovered 5 common HVAC problems and how they can be treated or avoided altogether.

Keeping your HVAC unit properly maintained and serviced will help you avoid air conditioning interruptions, structural damages, and premature unit replacement.

Ignoring HVAC problems can lead to catastrophic damages to your home, lower breathing air quality, and even lead to potentially fatal gas leaks.

Sources:
energy.gov/energysaver/common-air-conditioner-problems
epa.gov/iaq-schools/heating-ventilation-and-air-conditioning-systems-part-indoor-air-quality-design-tools
energystar.gov/campaign/heating_cooling/maintenance_checklist