1. Application

Residential Vs Commercial

Commercial air conditioning is used in commercial settings while residential air conditioning is used in residential settings.  Comparison completed, right?  Well, not exactly.

Even if you took two identical air conditioners, installed one in a business and one in a home, there would be significant differences between the systems.  Let us delve deeper into the world of Heating, Ventilation and Air Conditioning (known as HVAC, or often just referred to as Air Conditioning) from a Brisbane’s Air Conditioning team of experts perspective.

  1. Usage vs Exposure

Commercial worker exhausted

Commercial HVAC systems are used for a greater proportion of time compared to the hours we spend in that environment.  Let’s break that down…

It can sometimes feel like we live at work, with about a third of our life spent at work on average.  Commercial air conditioning systems are typically run for 8-10 hours per day Monday-Friday, if not 24 hours, which equates to an average of 40-50 hours/week.

Most of the remaining two-thirds of our time is spent at home (i.e. 14-16 hours).  However, Aussies typically only run their domestic air conditioners for 6 hours per day.  This equates to 42 hours/week.

Looking at the stats, commercial and residential air conditioners are typically run for similar hours per week.  However, we spend up to twice as much time at home.  Therefore, commercial AC units have greater usage when compared to our exposure to that environment.

  1. Units Types

There is a wider range of commercial heating, ventilation, and air conditioning (HVAC) systems out there compared to residential systems, with some overlap.  There is also a range of AC Systems often seen in apartment complexes and high-rise accommodation buildings that can be used for residential or commercial application.

Common Home HVAC Systems:

Residential Service and Repairs - ActronAir Ducted

  • High Wall Split Systems (Ductless AC Units)
  • Room Air Conditioners (RAC’s aka Box Units, Window Units or “Window Rattlers”)
  • Ducted Split Systems
  • Evaporative Coolers (in dryer climates)

Common Residential Complex HVAC Systems:

Residential Brand Daikin OR Residential Install - Daikin

  • Wall Split Systems
  • Ducted Split Systems
  • Water Cooled Package Units
  • Cooling Towers
  • Chillers
  • Chilled Water Fan Coil Units
  • Variable Refrigerant Volume (VRV) Systems

Common Commercial HVAC Systems:

Commercial Installs

  • Under Ceiling or Wall-Hung Split Systems
  • Ducted Systems
  • Air Cooled or Water Cooled Package Units
  • Evaporative Coolers
  • Central Plant / Air Conditioning
  • Cooling Towers
  • Condenser Pumps and Motors
  • Chilled Water Pumps and Motors
  • Water and Air Chillers
  • Reciprocating and Scroll Packaged Chillers
  • Heater Banks
  • Variable Speed Drives (VSD)
  • Variable Refrigerant Flow (VRF) Systems
  • Variable Refrigerant Volume (VRV) Systems
  • Building Management Systems (BMS)
  • Car Park Ventilation
  • Fresh Air Systems
  1. Brands

Air conditioning brands

In theory every aircon brand could be used for residential or commercial application.  However, there are a number of brands that specialize in the manufacture of commercial HVAC equipment.  This includes, but is not limited to:

Many brands also produce a commercial-specific range.  Examples include:

  1. Design

Air Conditioner Design

Commercial air conditioning set ups tend to be modular in nature, compared to domestic stand-alone systems installed in houses.  By design, a variety of components can be configured in different ways to suit the specific needs of the building served.  This makes sense give the almost endless possible business configurations within a given facility.  This configuration can also change over time as tenants or owners come and go.

At an entry level, an air conditioner can consist of single stage system, designed to produce just heating or cooling.  While these tend to be cheaper than other options, they are also relatively inefficient and work at full capacity even when it is not required.  These are commonly found in homes, particularly rental properties (where the owner does not have to pay the power bill…).

More advanced air conditioner models are designed to offer variable fan speeds to cut down on power usage.  These can be found in all settings.  However, these are still relatively inefficient when compared to multi-stage systems and therefore more expensive to run in the long term.

Multi-stage systems are designed to work at the required capacity and only ramp up to full capacity when needed, making them the most efficient AC option.  These are more commonly found in commercial settings.

Zoned systems are another design option worth mentioning that can be used to control heating or cooling to individual parts of a home or business.  This is done by specifically design zone valves and dampers inside the vents and ductwork that selectively block the flow of air.  This is a valuable design feature that prevents an AC system from heating or cooling areas of a premises not in use.  Business zoning systems are more high-tech than residential zoning system.

  1. Equipment Location

Hitachi Split System Outdoor Location

Think about where you see air conditioning units when out and about versus at home.  Home Outdoor AC Units (condensers) are often installed down at ground level on a slab or wall bracket in walkways and easily accessible areas.  In comparison, commercial condensing units are typically located up out of the way and inaccessible to general public.

Commercial HVAC units can be found on roofs, plant rooms and garage/basement locked areas.  This makes sense when you consider the value of floor space in commercial facilities.  There is also logic in removing units from easy access – to reduce the risk of interference (both intentional and unintentional).  This also allows for service and repairs to occur without disruption from passers-by.  Furthermore, it helps reduce noise pollution on the ground level and air pollution from outdoor units entering a building.

  1. Customisation

Industrial installation

Further to typical commercial AC design, building air conditioning systems allow greater customisation by necessity.  As previously mentioned, systems are usually made up of modular components that can be added or removed where desired.

In addition to the modular nature of many commercial systems, Building Management Systems (BMS) are commonly tailored to the building HVAC set up required.  BMS systems control and monitor building mechanical and electrical and can be connected to wide range of AC Units.  This computer technology is commonly seen in high-rises, office blocks and industrial facilities.

  1. Complexity

Residential wall air conditioner

Far more is expected from a workplace HVAC system, and the commercial environment in general, and commercial AC units tend to be more complex to meet these expectations.  In comparison, a residential air conditioner is typically operated to heat and cool a single family dwelling with relatively static requirements.

Building air conditioning is not only likely to be larger but can also be segmented into different offices and/or departments that have different heating and cooling requirements.  The aircon system needs to account for several thermostats that control various areas all at one time.  For example, a company may manufacture, process, sell or store items that require specific temperatures.  Alternatively, a space may be used to hosts conventions or large groups of people will require adjustable temperatures so that everyone remains comfortable.  These varying needs drive the additional complexity of commercial HVAC systems.

  1. Environmental Impact

Air conditioning design can have an environmental impact in terms of resources required to run it (think power/water/gas).  Single stage fixed speed systems seen in residential settings are far more resource-hungry than multi-stage, variable speed inverters more commonly seen in commercial premises.

For those who are interested in sustainable cooling and/or heating, the water source heat pump, or really any Geothermal Heat Pump, is the way to go.  Water source heat pumps are still relatively uncommon as they require proximity to a body of water, hence the name geothermal heat pumps.  However, they are rapidly escalating in popularity.

Another emerging type of heating and cooling system is Active Solar Thermal Systems.  These use free solar radiation to reduce peak demand on resources.

Furthermore, computer Building Management Systems (BMS) are increasingly improving HVAC system management and performance.  Increased use of economy cycles, night-time passive ventilation, and heat recovery are all possible with improved air handling control strategies.

The refrigerant the system runs on is another important environmental consideration.  More on this in the following point #10.

  1. Refrigerant

Air Conditioning Refrigerant (in gas and fluid form) transfers heat energy between the indoor and outdoor units of the air conditioning system.  As commercial AC units tend to have a longer lifespan, more of them run on older types of refrigerant compared to residential air conditioners.  Different refrigerants can also affect energy efficiency and performance in extreme conditions.

Older gases such as chlorofluorocarbons (CFCs) and hydrochlorofluorocarbon (HCFCs) are being phased out, and new refrigerants with low global warming impact are being introduced.  Natural refrigerants are also being more widely used.

R22 refrigerant is an ozone-depleting hydrochlorofluorocarbon (HCFC) that is being phased out in many countries.  In the commercial setting, R22 is still frequently used for repairs.  In the domestic setting, the cost of the R22 gas often renders repairs no longer financially viable and commonly signals time for AC system replacement.

R410A refrigerant is a more-environmentally friendly non-ozone depleting hydrofluorocarbon (HFC) used in all settings.

R32, the successor to R410A refrigerant, is an even better non-ozone depleting option with a significantly lower global warming potential (GWP) factor than R410A.  R32 is currently more common in residential air conditioners, but will increase in popularity in commercial setting as systems are replaced over time.

  1. Capacity

Kilowatt (kW) or British Thermal Units (BTU’s) rating refers to output power and is a measure of air conditioner capacity.  Reverse cycle air conditioning systems have 2 ratings; the first one refers to cooling capacity and the second refers to heating capacity (typically a higher number).

In houses, air conditioners with cooling capacity of 2kW to 25kW are typically seen.  In warehouses, laboratories, office complexes, and other commercial spaces, air conditioners with much higher kW ratings can be found. Eg. 10-100kW+.   Furthermore, Packaged Units can be built to higher capacities than standard units eg. 100-200kW

  1. Power

Energy Power Saving

The amount of power consumed by commercial and residential aircon units varies dramatically.

Commercial systems typically draw more power due to the higher workloads expected from them.

In Australia, HVAC systems account for as much as 30% of commercial energy use and costs in buildings and office spaces.  As well as the impact on total facility energy use and costs, these systems also dominate peak building electricity demand.

Interesting, the energy usage figure is higher in homes with air conditioning accounting for up to 40% of residential energy use.  So while a residential aircon unit may use less power compared to a commercial aircon unit, the proportion of power used compared to usage for the property overall is higher.

  1. Phase

Three phase power

Home air conditioners tend to run off single-phase power which is the usual power supply serving houses.  By comparison, commercial and industrial air conditioners typically run off three-phase power which is the norm in commercial facilities.

Single phase power requires a single wire to connect the circuit, whereas three phase power requires three wires.  Three-phase power allows for greater voltage regulation and is more efficient than single-phase as it requires less conductor materials for the same amount of power generation.

  1. Energy Efficiency

Three phase air conditioning systems, typically found in commercial settings, are more efficient than single phase aircons typically found in the home.  That’s not to say you can’t find three phase air conditioners installed in houses.

There are also premium versions of many systems, especially ducted, that can further improve the efficiency for homes and businesses.  However, there is more to the story.

Wall split air conditioners are the most energy efficient systems.  Wall splits are more common in homes compared to ducted, package and other types of commercially installed AC Units.  From this angle, residential air conditioning could be considered more energy efficient.

Air conditioner efficiency is measured by the energy-efficiency ratio (EER); the higher the EER value, the more energy efficient the aircon is.  EER is a ratio of the output (capacity) divided by the power input.  Using this formula, the energy efficiency of an air conditioner decreases as the capacity (kW rating) of the system increases. Eg. a 2.5kW wall split air conditioning system will automatically have a greater energy efficiency than a 7kW system.

In general, the higher quality the manufacturer, the more energy efficient the air conditioning units.  Daikin have designed a 7-star energy efficient system, called the US7.  Only the 2.5kW system is rated 7 stars because, as mentioned above, as energy efficiency decreases as the capacity (kW rating) increases.

  1. Heat Load

Choosing an air conditioner for a house is often based on room size and house design.  However, for commercial buildings, heat load should be considered for all air con installations.

Heat load depends on size of area to be cooled, number of occupants, size, position, shading and coverings of windows, and heat generated by lighting, equipment, and machinery (including computers, photocopiers, etc.).  The capacity of an air conditioner required for a business can be calculated from specific heat load equations.

  1. Noise

Noise is a greater issue in residential settings compared to commercial environments.  This makes sense given that you obviously want to be able to sleep at home (and not usually allowed to sleep on the job…).  Residential noise restrictions also exist, with good reason.

Noise levels of aircons are measured in decibels (dB), with indoor and outdoor units having their own ratings.  For split systems (ductless and ducted), outdoor air con noise is louder than indoor.

Newer units are designed to be quieter than older units.  Special features allow for quieter operation indoor with Quiet Mode/Function available on many higher quality AC units.  These are commonly tailored to the domestic market.

Commercial air conditioning units are significantly louder than residential counterparts.  For this reason, among others, units are often installed on the roof, basement carparks or plant rooms to avoid noise pollution.

Regular maintenance of AC units can help reduce unwanted noise in many ways.  Blocked filters, unbalanced fan motors, and loose components can all lead to increased noise production.

  1. Responsibility

In the commercial setting, there is a wider range of people involved in approving, installing, repairing and maintaining air conditioning.  Developers, Builders, Building Owners, Occupants, Body Corporates and Facilities Managers come to mind, just to name a few.

In the residential setting, home-owners are primarily responsible for installing and repairing any air conditioning in their house.  If a house is tenanted, tenants may be able to install air conditioning themselves but only with approval from an owner.

Occupants of a home or business are typically the ones responsible for maintenance.  Given that occupants are not always owners, it’s not surprising that maintenance ball is often dropped, and sadly air conditioning units can be left to fall apart and fail to reach full life expectancy.

  1. Temperature Sensing

Temperature

Many humans expect a perfect temperature-controlled environment at work, whereas they may be more forgiving at home.  This is not completely unreasonable given we are being paid to be productive and expect a certain level of comfort in order to achieve this.

To facilitate an optimum work environment, temperature sensing comes in many forms in commercial settings.  For most systems, this tends to be in the form of multiple sensors providing feedback to thermostat/s throughout the commercial facility.  This can also be achieved through the use of individual high wall split units, however wall splits are more commonly used in homes for human comfort.

Issues often arise in open-planned offices and the like where one sensor is responsible for controlling the ambience of a large area.  Personal preferences can be conflicting. E.g. Young skinny-mini who can’t seem to warm up despite five layers of clothes vs middle-aged female experiencing “tropical” flushes as they transition into a new phase of womanhood.

  1. Control Systems

There is a vast range of AC control systems available for homes and businesses, from simple on/off buttons through to intricate Building Management Systems (BMS).  Businesses often elect for a wired AC controller, rather than a wireless remote seen in homes, to prevent controls going missing at the hands of employees or even customers.  It’s also not uncommon to have a lock-box around a wall controller to prevent constant temperature and setting battles that can occur in the workplace (sure many people can relate!).

  1. Wifi

WiFi control tends to be a more common feature in home aircon set up.  Controls in a commercial environment tend to be limited in nature to avoid temperature/setting battles mentioned previously.

The ability to control the home AC from afar (or from the comfort of the couch or bed) is also more appealing to a homeowner.  Imagine being snuggled in bed on a chilly winter morning, and being able to reach out, grab the phone and turn the air con on heat to take the chill off the air before having to step out of bed.  Six-months later, imagine driving home from work and being able to turn the air con on to cool down the house ready for you to arrival into a perfectly chilled environment.

In the workplace, AC systems are typically manually or automatically turned on at the start of work and turned off at the end of the day.  There usually isn’t the need to turn the AC system on remotely because if the AC is on, someone is onsite and able to control it.

  1. Features

A greater range of features are typically seen in residential air conditioners to accommodate wide a range of personal preferences.  For business, the HVAC system needs to function as designed, without the need for all the bells and whistles.  The system is there to serve a purpose, without the need for optional extras that may be used to upsell a home AC system.

  1. Drainage

In theory, residential and commercial AC drainage is the same; water is drained away from the air conditioner into a drainage point.  In practice, this can be far more intricate and complex in a commercial building than a residential house.

Every component of a commercial HVAC system is larger than that of a residential system, including the drainage set up.  As residential units serve a much smaller area, the entire system usually drains in a single pan that is placed outside the house.  A commercial HVAC system consists of multiple pipes and pans for drainage purposes to ensure complete water removal and to eliminate the possibility of overflowing.

Commercial AC drains often call for serviceable p-traps to be installed to allow for complete maintenance to be carried out.  It is recommended that serviceable P-traps be installed as it common for condensate drains to become clogged.  If traps are not serviceable, it is not possible to guarantee they are clear.  If they become clogged, an AC unit drain tray will overflow and damage the ceiling plus any electrical items below the unit.  Obviously best to avoid this when the electrical items are typically computers, printers, scanners and/or other business-essential equipment.

  1. Filters

Air conditioner filter

Filters are an integral, yet often overlooked, part of an HVAC system.  A filter helps to increase the efficiency and longevity of a system by protecting it from dust and airborne particles.  It does this by providing a physical barrier between the air intake and moving parts of the AC system.

A wider range of filters are used in commercial heating and cooling systems compared to home air conditioners.  Ducted panel filters and manufacturer-specific split system aircon filters are commonplace in homes, compared to pleated, pocket/bag, v-bank, separator, carbon and HEPA filters in commercial settings.

Some filters are designed to improve the quality of the interior air.  Furthermore, some AC systems also have a filter at the air exhaust, as well as at the usual air intake, which further prevents any pollutants from blown back into the interior environment.  These specialized filters are more commonly found in commercial settings.

  1. Ventilation/Fresh Air

The V in HVAC stands for Ventilation and greater consideration is required for business premises.

Residential systems have windows that aid in proper ventilation.  In comparison, commercial buildings often have other components in place of windows, for more intricate ventilation.  It is also a common building requirement to have suitable ventilation and fresh air systems in place.

Adding Fresh Air to a heating or cooling system accomplishes two primary goals; First, it controls building pressures and secondly, it increases indoor air quality by diluting polluted or stale indoor air.  Many fresh air systems will vent cool air from inside the property and replace it with external air every couple of hours.  This is to ensure that levels of internal pollutants are kept low and air quality standards are kept high.

Ventilation system/s can be similar for a home or business, except they are typically larger scale in the commercial setting.  It is crucial to maintain proper ventilation, no matter what type of HVAC system you have.  The health of a ventilation system will impact the indoor air quality of any premises.

  1. Humidity

Air condensation and humidity

Humidity control by commercial air conditioning systems is a must to comply with health regulations in the workplace, whereas it is rarely considered in the domestic setting.  The humidity and temperature requirements in a residential dwelling do not vary much which is why the HVAC equipment used in the two environments is very different.

Low humidity in buildings should be avoided as it can dry out nasal membranes which act as a primary means of defence against airborne viruses and diseases.  On the flipside, research shows that virus survival decreases with decreased humidity – viruses survive better at humidity above 60%.  Therefore, it is recommended to keep relative humidity between 40% and 60% to create conditions that reduce the risk of infection through airborne droplets while preventing the drying out of mucous membranes in the nose.

HVAC systems can also offer built-in humidity control, and both humidifiers and dehumidifiers available as optional extras for various heating and cooling systems.  People that live and work in very dry environments or the tropics may find these additions to an AC system essential.  However, some people prefer to install separate humidifier or dehumidifier systems so that they can manage the humidity of their environment without also having to turn on the air conditioner.

  1. Standards

AIRAH

There are well-established standards for air conditioning maintenance in countries around the world.  As with most things, there is greater guidance and governance of commercial air conditioning compared to the domestic.

The Australian Institute of Refrigeration, Air conditioning and Heating (AIRAH) is a specialist, not-for-profit technical organisation providing leadership in the Heating, Ventilation, Air Conditioning and Refrigeration (HVAC&R) sector in Australia.  AIRAH produce a range of primary commercial equipment-based Technical Documents providing guidance on all HVAC&R matters, including the DA19 Manual that has been the definitive reference for maintenance in Australia for more than 20 years.

There are a range of laws and codes that businesses must comply with.  For air conditioning, this includes the Building Code of Australia (BCA) contained within the National Construction Code (NCC).  This Australian code provides the minimum necessary requirements for safety, health, amenity and sustainability in the design and construction of new buildings and new building work in existing buildings.

  1. Licensing

There is often additional licencing involved when it comes to commercial HVAC, especially building air conditioning works.  For example, in Queensland Australia, individuals and companies must hold a Queensland Building and Construction Commission (QBCC) licence to carry out building works valued over $3,300 or of any value where it involves Mechanical Services.  This includes constructing, installing, replacing, repairing, altering, maintaining, testing or commissioning any of the following for a building; air-conditioning, air handling systems, equipment in which a refrigerant gas is (or is to be) used and refrigeration.

Commercial facilities can also require certain business licencing and qualifications for work to be undertaken onsite.  For example, many shopping centres in Australia require a company to have CM3 Contractor OHS/WHS Prequalification before being allowed to carry out air conditioning repairs, service or installation works at the facility.

  1. Technicians

Daikin Air Conditioning Technician

*Photo from Daikin

Different HVAC technicians tend to specialise in commercial or domestic HVAC systems as both the units feature unique mechanisms and function differently.  Many technicians could in theory attend to both home and business air conditioners, however skills and experience can vary dramatically.

Even if technicians have the same base-level qualifications and licences, a commercial HVAC technician typically has a wider range of experience on more complex air conditioning systems.  This is necessary due to the complexity of equipment found in a business setting.  Business owners are also less forgiving of mistakes or oversights that could occur with less-experienced techs.

  1. Maintenance Requirements/Benefits

Fully functioning and well maintained HVAC systems are intended to provide comfortable conditions within the building they serve, especially in commercial settings.  Commercial AC supports business processes and systems as owners and occupants rely on aircon systems to successfully operate their businesses.  Failure to maintain HVAC systems reduces the useful life of the equipment, increases operating costs, and introduces unreliability, dissatisfaction, and risk to a business’ operation.  Failure to maintain is risky and ultimately creates costs and reduces returns.

Issues such as climate change, energy efficiency, water conservation, building performance and carbon management are all high on the political and social agenda in the twenty first century. Regulators, building owners and system operators need to address these issues in their policies and practices and consequently maintenance is high on the agenda and increasingly in the forefront of responses.

Maintenance is about energy and water, noise and vibration, efficiency and control.  Failure to maintain is unsustainable.  Maintenance improves safety, increases efficiency, improves reliability and increases satisfaction.  This is most important in the commercial environment.

  1. Maintenance Frequency/Tasks

Commercial air conditioning service

Australian Institute of Refrigeration, Air conditioning and Heating (AIRAH) calls for monthly maintenance of HVAC equipment used in a commercial setting.  Some maintenance tasks are recommended monthly, such as checking major components and drains, while others are recommended every 3, 6, or 12 months.

By comparison, a minimum of annual servicing is recommended for residential air conditioners used for human comfort.  Homeowners can carry out some basic maintenance given that home aircons tend to be less complex than commercial air conditioning.  Occupants can help maintain their AC units between major services by visually checking the AC system every few month and cleaning filters when required.

Any technical maintenance, including fully opening the units and handling electrics, is obviously best left for a fully qualified technician.  It is recommended to seek professional help if notice any abnormal noises, sights or smells from an air conditioner unit in the home or business setting.

  1. Maintenance Implications

Failure to maintain a home AC system can have consequences, but not as serious as those in a commercial setting.  Failure to maintain business aircon can have a wide range of implications.  These include poor air quality, poor employee and customer comfort, poor productivity from employees and equipment, excessive costs, and health risks.  There are also further consequences if fail to comply with building standards, workplace safety, health regulations and/or lease agreements.

The maintenance cost of commercial HVAC systems is more than that for residential units for various reasons such as complexity of components, the size of the units, difference in mechanisms and frequency required.  For a commercial unit, you need highly experienced and skilled technicians to ensure  perfect installation, effective maintenance, speedy repairs and smooth daily operation.

  1. Hibernation

Cooling Tower

When temperature adjustment in a building is not really required, it’s natural to want to turn off the air conditioning until needed.  This frequently occurs in the shoulder seasons at home (Spring/Autumn) where temperatures can be mild.  When hibernating an air conditioning system, greater consideration and consultation is required in a commercial setting.  This is particularly true when water cooling is involved.

Implications at home tend to be limited to build up of mould within indoor units, seizing of motors, and/or damage due to vermin or other wildlife making themselves at home in the AC units.

In business settings, these outcomes can also occur in addition to others.  Modern buildings are not designed to be shut down for extended periods of time.  People aren’t the only source of contaminants in buildings. There is often a need to ensure a minimum background amount of ventilation and operation is maintained to limit health and equipment failure risks upon return to work.

Cooling towers and condenser water systems are prime examples systems that should not be turned off without professional consultation.  In these systems, the risk of Legionella disease increases when the equipment is idle and water becomes stagnant.

  1. Indoor Air Quality

Indoor air quality is more heavily impacted by design and maintenance in a commercial setting compared to residential environment.  Some of the key commercial considerations mentioned so far in this article include type of filters (point #23), ventilation and fresh air systems (point #24), humidity control (point #25), maintenance (points #29 & #31), and hibernation (point #32).

Many advances in commercial building automation and HVAC control will also improve indoor air quality control.  The importance of fresh, clean air is understood and increasingly appreciated in modern workplaces, with increasing emphasis placed on controlling dust, bacteria, odours and toxic gases.

  1. Modifications/Repairs

Commercial units are usually made up of modular parts that can be built upon as needed.  This increases flexibility and allows owner/occupants to make greater changes to the heating and cooling as needed.  It also helps in the construction of a business HVAC system, as the parts are easier to handle independently.

Residential systems, on the other hand, typically comprised of two units that must work together.  If one half of the system fails, both units must be replaced.  The entire system also has to be replaced if the owner wants to make major changes to the level of heating and cooling.

Commercial repairs tend to be time critical, especially in high-rise buildings with windows sealed shut and typically higher heat loads (for more info on heat-load, see point #15 above).  Many businesses have a maintenance agreement in place with an air conditioning company.  Part of that agreement includes special rates for repairs call outs and priority attendance for such breakdowns.  These technicians also know the systems well from regular servicing of the equipment, which reduces time and costs in diagnosing given they know where everything is.

  1. Parts

Generic parts more common for commercial systems e.g. Indoor and outdoor fan motors, compressors, and the like.  Home air conditioning systems have some generic parts, but mostly require manufacturer specific components.

Given the longer lifespan of commercial aircons, genuine parts tend to be available longer than residential aircon parts.  This can be frustrating when a home air conditioner doesn’t feel that old but suddenly parts are no longer available and you’re up for the cost of a whole new system.

  1. Insurance

There are a wide range of insurance policies variations for houses vs business premises.

There are some items of common coverage, such as motor fusion and storm surge damage, but business policies tend to have more inclusions.  Obviously they tend to cost more as a result!  Residential insurance is much more standardized than commercial policies because businesses have a variety of different needs

Commercial policies sometimes offer compensation for lost business income.  If an accident causes a business to shut down or interrupts your work, such as HVAC system shut down, business interruption coverage can pay for the income lost when you unable to operate.

Business policies also allow coverage to address specific risks.  This could include failure of an air conditioner in a temperature-sensitive server room or laboratory.  Commercial policies can also allow additional costs to be covered, like meeting new or updated building codes when installing a new AC system.

  1. Causes of Damage

Both residential and commercial air conditioning can experience motor fusion and storm surge damage, along with vermin damage, power surges, physical damage (intentional or accidental), or other causes of damage.  However, due to typical location of commercial HVAC (e.g. roofs or plant rooms, locked up, out of human reach), physical damage is less common to business air conditioners.

In the home, vermin damage is more commonly seen due to AC units being in closer proximity to the pesky critters’ natural habitat (think garden, trees, rocks, etc.).  Power surges are the result of fluctuations in electrical current and can impact air conditioners in all settings.

  1. Life Span

Old Air Conditioner

As a general rule of thumb, the larger the system then the longer the expected lifespan.  Therefore, commercial air conditioners tend to have a longer lifespan due to their naturally larger sizing.  However, air con life span depends on many other factors including but not limited to unit type, application, usage, maintenance, and exposure to the elements.

Commercial HVAC life span is helped by the fact that routine maintenance more frequently occurs compared to home air conditioning.   Saying that, there can obviously be cases of “lemons” being installed in the commercial setting that barely last their manufacturer’s warranty period.  Furthermore, some home air conditioners can run for decades if infrequently used and maintained well.

  1. Warranty

Residential air conditioning units tend to have longer manufacturer warranty periods compared to commercial air con units.  Most residential aircons have a standard 5 year manufacturer’s warranty period.  Commercial AC Units come with warranty periods for 1 – 5 years, depending on application.

Standard installation warranty on all new air conditioner installs is 1 year.  Most air conditioning installers offer this installation warranty.  Commercial HVAC installs or repairs are often subject to a Defects Liability Period (DLP), which is a fixed period of time from work completion from which the contractor must return to site to rectify any defects.  Standard DLP can be 6 months to 24 months.  Businesses can include a clause in a relevant contract to withhold a portion of the installation or repair costs owed to the air conditioning company until the DLP period has ended.

Ice Blast Pty Ltd offers to extend the standard installation warranty in domestic settings from 1 year up to 5 years from installation date if the air conditioner system is serviced by Ice Blast annually.

For commercial settings, a custom HVAC maintenance agreement is available to enable similar extension of the installation warranty.

  1. Costs

As mentioned previously, heating and cooling can account for significant power usage and therefore costs (up to 30% in commercial and 40% in residential settings).  Within businesses, as well as the impact on total facility energy use and costs, aircon systems also dominate peak building electricity demand.

The capital and maintenance costs of HVAC also comprise a significant proportion of commercial building costs.  Costs can be minimised through good system design (especially accurate sizing), and routine servicing as per best-practice guidelines.  Investing in superior control systems and zoning can also result in substantial energy savings.

Advances in engineering enable the measurement of many factors that influence the comfort of building occupants, such as humidity, air movement and surface temperatures of nearby objects, like windows.  Optimising these factors can yield further energy savings.

Computer technologies are increasingly improving HVAC system management, performance and cost savings.  Increased use of economy cycles, night-time passive ventilation and heat recovery are commercial options for improving costs.

Inverter technology is another cost-saver, more commonly seen in the commercial environment.  An inverter works like the accelerator of a car, gently increasing/decreasing power as required.  Inverter based AC systems can achieve the desired room temperature quicker and maintain it without fluctuations which means savings in running costs (and uninterrupted comfort!).

Reverse cycle air conditioners also offer a cost-saving as they are significantly more efficient (and therefore cost less to run) comparted to more commonly available ‘minimum standard’ models.  These are a standard in business setting.  It is worth noting that minor adjustments to thermostat set points can often be made, resulting in energy savings without greatly affecting occupants.

BONUS POINT:  Value

Given the extensive differences between commercial and residential air conditioning, which do you think is more valuable?

Both have a part to play in creating optimal environments, whether it be for humans, pets, equipment or products.  Given the amount of negative outcomes possible when commercial HVAC is not properly designed, installed, controlled, maintained or repaired, the value in commercial AC seemingly comes out on top.

Many homes don’t have or need air conditioning.

Residents can be happy to rug up warm with layers of clothing and/or snuggle by a fire in winter.  Can’t see a group of co-workers huddling up together in the workplace to keep warm!

During the summer, doors and windows can usually be opened up at home in conjunction with fans.  By comparison, windows that open and allow a cooling breeze are somewhat of a luxury at work!  Hence the added value air conditioning has in the commercial setting.