To make an educated decision when selecting a surge protector for an HVAC system, it is important to dispel some common myths. With so many brands, types, and choices on the market, it can be difficult to cut through the noise and figure out what product is right for your application. Surge protectors are available for both ducted and ductless systems and should be installed by a licensed professional.

Let’s examine three myths about HVAC surge protectors so that you can make a better, more informed decision.


Myth 1: All surge protectors are created equal.

While many surge protectors appear similar at first glance, there are actually a variety of factors to consider when choosing the right one for an HVAC system. Make sure to look for a surge protector that is specifically designed for HVAC systems. Select HVAC surge protectors with features that include the ability to withstand multiple repetitive power surges, extreme temperatures, and humidity.

Even within the HVAC surge protector market, some have better performance ratings that indicate how well the protector will do its job under extreme power surge situations. The Nominal Discharge Current Rating from UL (Underwriters Laboratories) is the recognized industry standard for test ratings of surge protectors. Another differentiator is advanced Gas Discharge Tube (GDT) Technology. GDT technology dissipates a surge across multiple pathways, effectively dissipating a larger surge than other models on the market. The GDT in itself is classified as a surge arrestor and is a robust standalone component handling surge energy as high as 60,000 amps.


Myth 2: The more MOVs, the better the surge protector.

The Metal Oxide Varistor (MOV) is the part of the surge protector that absorbs excess voltage and dissipates it as heat to ground. So, you may think that the more MOVs in a surge protector, the better it will be at protecting your HVAC system. That is not true. Multiple MOVs in a circuit need to perform at the same time to ensure performance. This coordination of components is extremely difficult to design and manage. Thus, it leads to circuit failure as one MOV will take the brunt of the damage, leaving others less protected. The “weakest link in the chain” is the best way to describe it. A surge protector with fewer but larger MOVs is more effective at dissipating a surge.


Myth 3: Bigger is better.

It is not always the case that a bigger-looking surge protector ensures better performance. In fact, some of the larger surge protectors on the market may have a lower MOV rating than smaller models. The key is to look for a surge protector that is specifically designed for HVAC systems and has reliable performance ratings. Smaller, better-performing surge protectors also offer installation versatility and options. A good example of this is having the ability, with a more compact device, to install the surge protector inside a piece of equipment.

A bigger surge protector may present installation challenges. It’s important to make sure the surge protector you select will fit in the available space and that all wiring will reach the appropriate terminals.



Making an informed decision about which HVAC surge protector to purchase is important to protect your customer’s investment in dependable indoor comfort and your reputation. When it comes to surge protection for an HVAC system, don’t believe everything you hear. Now that you have learned about some common myths about HVAC surge protectors, you can feel confident in your decision-making process. With so many choices on the market, you are sure to find a surge protector that meets your needs and keeps your customers' HVAC systems operating dependably and efficiently.