FM Articles

What To Consider When Selecting Antifreeze for Heating Systems

Heating Systems

As temperatures drop during the winter, the last thing you want is for your property’s plumbing system to freeze and potentially cause extensive damage. Antifreeze is a liquid that contains chemicals that lower the freezing point of water, protecting pipes and other plumbing components from bursting. Without antifreeze, residual moisture in plumbing systems can freeze and expand, causing cracks in the pipes, joints, or other fittings in a heating system.

There are many antifreeze solutions on the market with a range of options to suit different needs. Below, we will cover four factors to consider when selecting antifreeze and explore different types of antifreeze available for certain applications.

The suitable product for your application depends on the system type, climate, and metal content.

Below are four factors to consider when selecting antifreeze for winterization:

  1. First, always check the manufacturer’s recommendations for the system you are working with. Producers will often have a preferred type of antifreeze suitable for the specific system.
  2. Consider the climate you are in when selecting the type of antifreeze. Some antifreezes are better suited for colder temperatures than others.
  3. Another factor is the freeze-protection level required for your plumbing system or the desired temperature coverage. Different antifreeze types offer different freeze protection levels, so it is essential to choose the right type to ensure adequate protection against freezing.
  4. Finally, the amount of antifreeze required depends on the size of the system you are protecting. Be sure to measure accurately and ensure the correct amount of antifreeze is added to the system.

The Different Types of Antifreeze
The main differences between most heating system antifreeze products lie in the percentage of propylene glycol used in each and the applications each is best suited for.

Antifreeze products made only with virgin propylene glycol are highly recommended because some boiler manufacturers state in their warranties that antifreeze made with virgin propylene glycol is required, or the warranty is voided. Recycled propylene glycol is captured and cleaned after use (mainly for de-icing aircraft). It is then considered a lower grade of propylene glycol and may still contain other ingredients even after cleaning.

An antifreeze with a triple protection inhibitor stabilizes pH to prevent corrosion, chelates, and hard-water minerals while also inhibiting scale and sediment formation.

  • Universal Antifreeze: A universal option offers versatility when the specific system requirements are unknown and can provide effective freeze protection in various situations.
  • Extremely Low-Temperature Coverage: This type of antifreeze has a higher concentration of glycol, providing lower freezing-point protection when undiluted, and is a solution ideal for systems requiring extremely low-temperature coverage.
  • Aluminum Heat Exchanger Systems: An AL version contains 60% glycol and is specifically compatible with aluminum heat exchanger systems, whose lower pH (acidic) can lead to quicker corrosion or degradation of components.
  • Solar Systems: Solar systems have unique needs for freeze protection. Solar System antifreeze is specifically designed for solar water heating systems. It provides excellent freeze protection while maintaining the efficiency of the solar water heating system. It can also be used in radiant tube heating systems and geothermal loops and is compatible with PEX and elastomeric radiant tubing.

Antifreeze is a crucial component of any plumbing system that is exposed to potential freezing temperatures. Choosing the right antifreeze can help prevent costly repairs and protect your heating system.

When choosing the right antifreeze for your plumbing system, check the manufacturer’s recommendations, consider the climate, and determine the freeze-protection level required for optimal protection. With these considerations in mind, you can ensure your heating system is ready to handle even the coldest winters.

Sean Comerford is a Technical Applications Manager at Oatey Co. He is a third-generation tradesman with nearly 20 years of plumbing experience, including serving as the lead plumber for commercial/residential new-construction, service and fire protection jobs. He holds a State of Ohio Fire Protection License for Sprinkler and Standpipe.