Commercial chillers are the unsung heroes that keep people and equipment cool. Learn how the two types of commercial chiller work and how to look after them.

Key Takeaways:

  • Chillers can be air- or water-based
  • Each design has its pros and cons
  • Proper maintenance is essential with either model
  • Working with HVAC experts keeps you safe and chillers working optimally

Commercial chillers are a vital component in the workings of their more famous partner: HVACs, or Heating, Ventilation, and Air Conditioning systems. These units do a hugely important job by transferring internal heat to an external location, keeping indoor temperatures stable in commercial settings across the country. 

Buildings ranging from hospitality and habitation hotspots to the vital medical and industrial sectors all rely on their HVACs to operate well, which depends in large part on their cooling systems staying frosty. Comfort, productivity, and even lives can depend on their performance.

These expectations naturally put steep demands on commercial chillers. Here in Florida, chillers are the unsung heroes of commerce, and they only get noticed when they’re not doing their job. Let’s get them a few more fans by appreciating their role and highlighting the necessary levels of maintenance to guarantee cool running.

Commercial chillers face a lot of heat

Commercial buildings have a lot more external heat sources to contend with than Florida’s near-constant sunshine and humidity. Our state is also subject to high winds, and wind flow around a building affects the circulation of air across surfaces like windows, doors, and vents. If not properly positioned, this crossflow can cause internal fans to work overtime to fight excessive warmth.

There’s a ton of heat lurking indoors, too. Commercial buildings are usually full of people, equipment (particularly computers), and electrical or comfort-based systems like lighting, radiators, boilers, and so forth. Human body heat may seem insignificant, but hundreds of people are radiating it all day in a confined space, this only adds to the thermal load of commercial sites. 

Keeping heat at acceptable levels is achieved via one of two types of commercial chiller systems: water-based and air-based. Each of these refrigeration approaches has its strengths, and both are practically identical when it comes to their hardware. It’s only how they do the cooling that differs significantly.

How water-based chiller systems work

Water-based chillers move heat from refrigerant vapor into condenser water. The refrigerant is usually condensed using the recirculated water from a cooling tower. The warmer water is then pumped away back to the cooling tower, which discharges the gathered heat into the atmosphere. Here are some pros of water chillers:

  • Require less ductwork
  • Can be placed pretty much anywhere on a commercial property
  • Far quieter than air chillers
  • Can effectively cool very large commercial spaces
  • Can last decades with proper maintenance

There’s a fairly even balance of pros and cons, with the downsides being:

  • Water costs money and, despite Florida’s significant rainfall, is already proving to be a scarce commodity.
  • Water chiller systems need to contend with contaminants like algae and bacteria, which requires the commercial site to have the further expense of a water treatment program.
  • Condenser water pumps and cooling towers add significantly to the initial installation cost.

The fact that they can conversely lower the overall running costs of commercial HVACs by using less energy than air chillers may not be enough to convince buyers. Now, let’s look at the alternative.

How air-based chiller systems work

Standard air chiller construction uses either mechanical refrigeration cycles or propeller fans to draw ambient air (outside air in its natural state) over coils that condense the refrigerant. Condensation then takes place inside the air chiller, which allows heat to be transferred out of the building and into the atmosphere.

This model has some advantages over the water-based design:

  • Lower price
  • More compact and self-contained
  • Popular with smaller structures
  • Less time and effort to install
  • Usually, lower maintenance
  • Won’t let you down in a water shortage because air is free (at least, for now).

The downsides are:

  • Often placed outside of commercial locations. Air chillers are vulnerable to a number of threats, including environmental damage, vandalism, and debris.
  • Dependence on a clear and steady airflow — a factor that can be impeded by poor placement, such as against or near high walls, in foliage-dense areas, or when multiple units are packed too closely together.
  • Shorter lifespan than water chillers, which can negatively offset installation savings. 

Top 6 chiller system maintenance tips

1. Inspect mechanical components and wiring regularly

Chiller parts may be crying for help when they get excessively loud. They can also show signs of breaking down if parts become discolored or motors and wire contacts become worn.

2. Clean your air and fluid filters

Mud, algae, minerals, and more can all conspire to clog your chiller’s tubes and filters. Follow the maintenance recommendations for your model to keep water sources fresh and filters brushed clean for more efficient heat transfer.

3. Dust-off condenser fins

Compressed air is a good way to blast off any debris, dirt, or oil that may be causing excess weight or blockages on your chiller condenser blades.

4. Look out for leaks

Essential lubricants and refrigerants can drip away because of issues like worn or loose pipes and tubes. Remember: refrigerant leaks can prove toxic. Some leakage of water or oil is considered normal around pump seals but always consult a professional if there’s any doubt.

5. Maintain a steady chilled water flow

Chilled water that moves too slowly will decrease system efficiency. Too fast, and it will erode parts and lead to vibration and excessive noise. Aim for a water flow rate of 3 feet per second or consult the manufacturer’s guidelines for optimum levels.

6. Invest in a VSD

Variable speed drives help match motor and load efficiency and can dramatically improve a chiller’s energy consumption. This is because VSD’s use less energy than constant speed designs, potentially cutting a chiller’s energy consumption by 30% and earning them a recommendation from the Environmental Protection Agency.

These six tips are a great maintenance starting point, but it’s always best to have a team of pros assess your current chiller system to provide you with reliable recommendations on installation, repair, and maintenance (and to keep you safe in the process).

Talk to UES to stay chill at all times

Deciding which chiller is best for your property is greatly aided by getting advice from seasoned experts. The Universal Electrical Team is licensed throughout the state of Florida, and we can bring over 20 years of experience to HVAC and chiller matters of all kinds. Visit our contact page and let us know if you have any chiller system installation or maintenance questions!