Coatings for Cooling Towers and Coolroom Repairs.

Did you know that cooling towers go through a lot in their lifetimes?

Everything from harsh chemicals, extreme temperatures, and rough daily movements from the fan drives and pumps.
Indeed, if a cooling tower could talk what would it say?

I am leaking, I am dirty, corroding, running too hot, too cold, have a terrible case of the jitters, have a bad disease, I’m about to explode.

All jokes aside cooling towers can’t talk, nor will they magically tell you what is wrong or what they need and that is why they need to be expertly inspected and repaired on a regular basis.
On top of this, it’s also essential to have a proper coating method (namely RepelCoat) that is designed for all types of cooling towers and materials to protect cooling towers, structures, and people.

We sat with the owners of FlowMatrix Darren and Jason, who have more than 33 years of experience in the cooling tower industry, to be able to better understand the space of cooling towers and more specifically why using RepelCoat will save your cooling tower, structures, buildings, and lots of money.

RepelCoat for Cooling Towers, Cool Rooms, and Structures:

Cooling towers come in all shapes, sizes, and variations of materials such as steel, fibreglass, timber and plastic. It is therefore important that a coating product “RepelCoat” was going to withstand, a chemical attack, high or low pH levels, corrosion, erosion from fast-moving water and grit, vibration, excessive movement, and foot traffic.
In 2018, FlowMatrix in Australia took a big step forward in terms of developing their coating system just for cooling towers, they called it RepelCoat, a registered trademark

RepelCoat consists of a range of coating products all designed to provide specialised coating systems for

  • Cooling tower flexible coating for installations
  • Cooling tower steel repairs to stop corrosion and leaks
  • Fibreglass cooling tower repairs to stop leaks and repair cracks/holes
  • Sealing water leaks in basins pits and tanks
  • Protecting pipework from chemical damage
  • Stopping steel support corrosion
  • Cooling tower plant room floors membranes
  • Steel roof surfaces under cooling towers membranes to stop corrosion and leaks
  • Pipework penetrations sealing through floors and roofs to stop water damage below
  • Cool store panel sealing
  • Grouting systems for concrete plinths and fibreglass to stop water leaks and damage, hollow core filling of cooling tower legs in cooling towers with coils .

Why Experience and Knowledge Counts:

When it comes to cooling towers, FlowMatrix has an abundance of knowledge and experience, having expanded across many fields. They don’t just service and repair cooling towers, instead, they utilise their knowledge and technical expertise to help companies get the best possible outcomes, all from designing the best range of coating systems for each situation and cooling tower type.

Darren explained just how severe and volatile cooling towers are, comparing the conditions to a marine setting, where waves and salt water completely ruin timber structures and metal structures, concrete and fibreglass over time.
Conditions inside a cooling tower are very tough on the unit and what splashes out or what comes out of the fans damages everything around it
“Cooling towers need various coatings on their surfaces to help prolong life and to also keep them running optimally both the unit and the materials around them”.

Having worked with every type of cooling tower for over 33 years, Darren and Jason believed there was nothing out there that genuinely provided a complete solution for any type of cooling tower, the type of installation, the mechanical parts, the supporting structures, the rooftops, plant rooms, pipework and more.
There was also nothing that offered a range of solutions to maintain an appropriate atmosphere, free of corrosion, bacteria, disease, damage and stress

Jason has a 10 years of cooling tower water treatment chemistry background as well as 3 years of specialized coating experience to go with his 8 years of cooling tower experience, so he understood more than anyone what causes all of the common cooling tower problems, and what was therefore required to bridge this gap.
Jason’s all-around knowledge, combined with Darren’s 33 years of cooling tower expertise, experience, and knowledge, FlowMatrix was able to produce and design the highest quality coating system formulations on the market today to combat all of the common cooling tower problems that cause so much grief.

Benefits Of Cooling Tower Coatings:

RepelCoat effectively protects against corrosion and is suitable for all steel cooling towers, including BAC (Baltimore Air Coil), Coolmaster, Evapco, F Muller, Fibreflow, Linear, Marley, Muller and Radic.
RepelCoat effectively repairs and protects fibreglass cooling towers including BAC (Baltimore Air Coil) Evapco, Aquacool, Super chill, Sulzer, Tencel, Tower Thermal, Shinwa, Coolboy, Lakeside

Other benefits include:

• Long-term corrosion and erosion protection
• Good compressive strength
• Not affected by biocides such as chlorine
• Great resistance to a wide variety of chemicals and high or low pH
• Reduced safety and health risks due to being clean and smooth finished surfaces
• Allows expansion, does not shrink or distort
• Can be cured and applied at room temperature within 2 hours
• Includes surface preparation to AS 1672.4
• Leaves an extremely hard-wearing long-life surface
• Bonds to steel will not lift away; any physical damage will be localised to the affected area
• Designed to withstand cooling tower water treatment programs
• Able to withstand high or low pH, high salt levels, acid, alkaline
• Reduces the growth of Legionella bacteria by eliminating corroded surfaces
• Stops water and chemical leaks into the environment
• Extends the life of the cooling tower by many years

Where you can use RepelCoat:

RepelCoat coatings can also be placed on the cooling tower’s exterior/interior, providing a durable barrier that adheres to steel, fibreglass, timber, and concrete, and repels corrosive substances. RepelCoat prevents corrosion and rust on the inside and outside of your cooling tower, as well as piping, penetrations, vessels, and concrete bases. A tank can be protected inside and outside to avoid corrosion and leaks, extending the life of your equipment.


A specialised coating method is required for cooling tower pipework.
RepelCoat is a line of cooling tower coating solutions created by FlowMatrix.
Cooling tower water and chemicals are splashed and sprayed onto pipework which causes existing coatings to fail, severe corrosion and pitting of steel, damage to stainless steel, concrete supports and floor steel reinforcement failure (concrete cancer), plastic pipe sunlight damage when coatings fail, and copper corrosion.
Pipes can fail and burst, crack and leak treated water into a plant room, onto a roof, or the ground. It costs a lot of money to replace damaged pipework and it can take weeks to cut the damaged section and valves out, and then replace it. What a pain!

The preparation and coating of steel, copper and PVC pipework connected to cooling towers are one of the RepelCoat systems.Hollow-core filling

Grout is most frequently associated with filling gaps between tiles, but it also plays a significant role in cooling tower repair. RepelCoat Grout was created by FlowMatrix to fix cracks in concrete pits, parts of concrete that had fallen off concrete plinths, general concrete fractures in pits and now to repair hollow cores in fibreglass basins and leaking hollow legs in BAC cooling towers


The cool room panels must be sealed to save money on operations. If the panels have gaps, the cold air can easily escape into the outside air. This causes ice to form in the fractures, weakening the panels by causing more significant gaps and buckling as the ice spreads. The harder the refrigeration system is forced to function, the more gaps and panel damage appear. The RepelCoat Sealing system includes surface cleaning, etching, primer coat, and topcoat. It’s a membrane system that clings firmly to the panels while being flexible enough to allow for slight panel movement due to expansion and contraction. Hundreds of thousands of dollars of refrigerated air are wasted every week from cool store panels that leak the cold air out into the surrounding warm air. It is a stupid waste of electrical energy that bumps up an operator’s power bills, causes the refrigeration equipment to run harder and wear out quicker, and the loss and cost of expensive refrigeration gas

If FlowMatrix notices that there are other potential issues with your cool room that go beyond coating systems, they can use their expertise to refer you to a company that can help you. Darren mentioned that they frequently refer all their clients to Coolclean, a Victoria-based company that provides cool room cleaning, maintenance, repairs, and services for cool room surfaces, fan coil units, evaporators, Penthouse units, and banana rooms and Alcoves.

You can check out their page here to see if they offer what you need can also be applied to the following cooling tower systems: Collection Basins, Chilled Water Tanks, Packaged Towers, Field Erected Towers, Distribution Decks, Chiller Plants, and Ice Storage Tanks.

RepelCoat coating system range:

The FlowMatrix team use their knowledge and experience to create a tailored coating system coating for each tower and job type.

Darren explained as an example, “in a steel cooling tower, there will be 3 systems for different jobs
• one that bonds to the steel base
• another to create flexibility
• and a chemical protectant coating

And so, we would recommend the most appropriate coatings for each cooling tower, system, and site.Here is the range of RepelCoat systems that could be useful for you:

RepelCoat Rapid RCR-200 / 300 / 400. These systems are used for coating the interior of mild steel, stainless steel, and fibreglass cooling towers. Structural steel supports. Steel ductwork and fan discharges. The amazing this about this system is the two-hour curing time between coats which is a great time saver for our clients.

RepelCoat PV-300 / 400. These systems are used on pipework, vessels, and tanks that are associated with cooling towers or refrigeration systems.

RepelCoat PUME-200 /300 Membrane concrete plant rooms, steel flooring or steel roofing coating systems.

RepelCoat Grout GSW-200 for sealing/repairing hollow cores in steel or fibreglass.

RepelCoat MP-100 Submerged concrete repair and resurfacing of pits and tanks.

Application process:

The FlowMatrix team use their knowledge-creating a tailored coating system for each tower;

Steel interior surfaces of cooling tower basins, casings, and walls. Tank interior surfaces. FlowMatrix disassembles steel panels, opens up access hatches and carries out a confined space entry procedure to gain complete access to carry out the RepelCoat coating system. Surface preparation is by sand / abrasive blasting or by hand preparation using bristle blasters, grinders and wire wheeling. This is the critical stage to get the surface clean and ready for a fantastic bond with the RepelCoat primer
The application of the primer is critical to ensure that the bond is sound, so mixing the products correctly must ensure the correct curing rate based on the temperature of the day and the humidity.
The mid-coat is a specialized product that bonds to the primer and the top chemical-resistant coating to allow movement without cracking the RepelCoat system. This is critical as cooling towers move, shake and vibrate due to the fan drives, water hammers from pipework and pumps, and maintenance people walking on the surfaces
The top chemical resistant coating is there to withstand the constant attack from chemicals, acid, alkaline, hard water, soft water, high pH, low pH, corrosion inhibitors, biocides, sodium hypochlorite, chlorine, erosion from water and dirt pounding against the surface like sandblasting
Fibreglass is a two-coat system with the primer being the flexible coating layer and the top coat being the chemical-resistant coating. All the aspects of the steel system apply except the primer/bonding is a different chemical reaction and bonding process

The following video is FlowMatrix application process:

If you need an expert to take a look at your cooling tower, cool room, equipment, any component that is not working, or if you simply need the best advice to get the longest life and best results from your cooling system, then give FlowMatrix a call.

The entire team are very knowledgeable and will most definitely be able to assist you.

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