Marine Equipment Manufacturers, Importers & Distributors

Air Treatment

The simplest way to improve your indoor air quality by killing the mould, bacteria and viruses that grow in your air conditioning system...


Is your Air Safe to Breathe?

Stella Systems is proud to be the exclusive Queensland distributor of Gelair Air Treatment. Gelair is a patented technology for delivering Australian tea tree oil vapour to kill mould, bacteria and viruses in air conditioning systems. Now actively used around the world for many applications including buildings, marine vessels and oil platforms. We don’t just sell the products; we also back it up with a complete air conditioning maintenance service via our marine engineering division Stella Marine.


What is Gelair?

A patented system, using a specially formulated gel matrix (block) that is placed in an air handling unit (AHU), where it releases specific concentrations of top quality Australian tee tree oil vapour throughout the air conditioning system. Tea tree oil (a 100% natural essential oil) is a broad spectrum anti-microbial and anti-fungal agent.

Australian grown and distilled tea tree oil is the main ingredient in Gelair. We use only the finest tea tree oil in our products, with every batch meticulously tested for quality.

Tea Tree Plant


A powerful and natural product, tea tree oil eradicates mould, bacteria and viruses. These nasties thrive in areas affected by moisture condensation such as air-conditioning units, bathrooms and kitchens. Condensation is a problem in hot and humid climates as well as cold and damp climates.

The health of your family, friends, employees and customers is a priority. That's why our environmentally friendly, natural product helps prevent the allergies and respiratory illnesses caused by harmful micro-organisms.

Why do I need Gelair?

Moisture build-up in air conditioning AHUs is inevitable. With Australia’s humid environment and condensation issues, our cooling systems provide the perfect environment for mould and bacteria to grow.

Mould & bacteria on a filter   Mould & bacteria in a duct   Mould & bacteria in a duct

If air conditioning systems are left untreated, we end up with:

  • The spread of invisible bacteria and viruses
  • The growth of mould throughout the system
  • A strong odour due to mould and bacteria
  • Unsightly stains on walls, ceilings and upholstery
  • Coating on the cooling coils which leads to inefficient heating and cooling
  • Increased energy costs and equipment corrosion
  • Release of allergy-causing spores and release of toxic gases
  • Increased instances of sick building syndrome: inhaling high concentrations of moulds, yeasts, bacteria and their spores and toxins is the most common cause of sick building syndrome.

By adding a Gelair block to your AHU, you have a natural, effective way of making sure your ducts remain healthy and more importantly, the air entering the occupant zones is treated for mould, bacteria and viruses.

Gelair block installed in the AHU of an air conditioning system

Benefits of Gelair

  • Kills mould
  • Kills bacteria (including legionella)
  • Kills viruses (including HSV & inhibits the H1N1 replication cycle)
  • Simple to install and no maintenance
  • Improves indoor air quality (e.g. for Green Mark assessment or to reduce sick building syndrome)
  • Kills odour causing bacteria instead of just masking the smell
  • 100% natural
  • No bacterial resistance issues
  • Treats the air, ducts and the rooms
  • Regular maintenance cycle (monthly applications) with no operational costs


GELAIR Products

GELAIR Air Conditioning Blocks (ABs)                                                          

Gelair block installed in a yacht

Gelair Air Conditioning Blocks are used in Air Handling Units (AHUs) of air conditioning systems for the control of mould and bacteria. They come in 4 sizes to match the capacity of the Air Handling Units:                                                                                                                      

  • AB0.5s are typically used in small rooms serviced by an AHU (6-12 BTU) in the room. These size blocks can also be used for split type air conditioning units.
  • AB1.0s are used in small AHUs (18-36 BTU) that service typically 2 or 3 rooms.
  • AB2.0s are used in up to 6 rooms or a medium size house or yacht (36 BTU).
  • AB4.0s are used in larger buildings and yachts with a central AHU (>36BTU). In much larger systems you will need to use multiple AB4.0s.                                                                  

*As a general guide use 1x 4kg block per m3/sec of airflow.

GELAIR Solution

Gelair Solution is used to clean cooling coils and other surfaces that may have mould and bacteria contamination. Gelair Solution is formulated to be both a sterilising solution as well as a cleaning solution.

Its major application is for sterilising cooling coils and is formulated so that it is viscous and will stay in contact with a non-horizontal surface for a period of time. It can be used on nearly all surfaces, but if being used on food preparation surfaces or soft plastics/rubbers you may only be able to leave it on for a short period. Water can be used to remove the small amount of material on surfaces cleaned with Gelair Solution.


How is Gelair Installed?

Just open up the block packaging and place the Gelair block in the AHU between the filter and the cooling coil (hot air return).

Gelair blocks are supplied in a vacuum bag so some of the solution will be left in the packaging. This can be poured into the AHU condensate tray and will help give an initial burst of tea tree oil vapour into the system. It will also help unblock condensate drains.


Who Uses Gelair?

Gelair has been used worldwide for over 10 years. It is used in a wide range of marine, commercial and industrial applications and can be installed in any type of air conditioning system.


Private Yachts
Charter boats
Offshore oil & gas


Office buildings
Hotels & resorts
Exhibition centres
Retail outlets
Private homes


Day care centres
Health clubs
Aged care


What is Gelair?

Gelair Air-conditioning Blocks are a biodegradable gel containing tea tree oil. When the air conditioning unit operates normally, the gel vaporises in the air, releasing the tea tree oil. The tea tree oil controls the mould and bacteria in the air handling units, ducts and rooms serviced by the air-conditioner.

Gelair Solution is a concentrated solubilised solution of tea tree oil. Mixed with other cleaning agents, this product is great for cleaning cooling coils in air handling units, ducts and other contaminated surfaces.


How does Gelair work?

The high air flow from the air-conditioning unit runs over the surface of the Gelair block, releasing tea tree oil into the air. Harmful micro-organisms are destroyed when the tea tree oil comes into contact with it. Tea tree oil effectively targets a wide range of micro-organisms, making it the ideal essential oil for the job. Gelair works by breaking the micro-organism’s cell membrane, destroying it in the process.


How much do I use?

As long as you correctly place the block, it will last about thirty days. To choose the right sized block for the space your air-conditioner services, view our products page.


Is it safe?

Whether natural or synthetic, high doses of chemicals can cause health problems. Gelair Air-conditioning Blocks release only small quantities of tea tree oil over a long period of time, making it a safe and environmentally friendly solution. Most people consider tea tree oil's low odour to be "fresh" and "clean". If you use Gelair as directed, it will not damage your health. We recommend storing Gelair safely away from children as it is toxic if ingested.


How can I tell if it’s working?

When you first insert your Gelair block, you will notice a faint smell of tea tree oil. The oil is beginning to do its job, controlling the mould and bacteria in your system. Signs your air is becoming cleaner include an improved odour and a decrease in symptoms caused by allergic reactions. The full effects of Gelair won't happen overnight- but it will happen soon!


Technical Information

For detailed information on tea tree plants and the effectiveness of tea tree oil, we recommend reading:


Brisbane: (07) 3890 5680
Gold Coast: (07) 5549 0556


Rivergate Marina and Shipyard
Unit 4, 17 Rivergate Place, Murarrie QLD 4172, Australia
Gold Coast
Unit 13/14 Hopper Ave, Ormeau QLD 4208, Australia
Phone: (07) 5549 0556