Surge Protection for HVAC – Short #285

This short podcast is from the Bry-X stage of the 7th Annual HVACR Training Symposium: Cheryl Klein's “Surge Protection for HVAC.” Cheryl is with DITEK, a veteran-owned company based in Florida, and has extensive knowledge of whole-home surge protection and HVAC-specific surge protectors.

HVAC systems may have their lifespans reduced by power surges (tens of thousands of volts within microseconds) or sustained overvoltage. Surge protectors specifically protect the equipment from power surges, though DITEK manufactures products that help manage sustained overvoltage (and undervoltage, which surge protectors CANNOT protect against). Nearby lightning strikes and high voltage from the utility company (especially after undervoltage) are common causes of surges. Everyone in the country has risks of power surges, but some areas are exceptionally high-risk, whether due to utility causes or climate (lightning storms).

Degradation is the invisible damage that occurs over time with repeated surges. Destruction can be associated with a specific event, like a direct lightning strike or a blown transformer. Surge protection helps with both; when a surge comes through, the surge protector directs the surge to ground instead of your HVAC equipment. DITEK uses thermally protected MOVs (TPMOVs) to redirect the surge; TPMOVs react to surges and change from a low-impedance state to a high-impedance state, effectively pointing the surges to ground, and only a clamped voltage makes it to the HVAC equipment. However, surge protectors will degrade with each event; DITEK's surge protectors have LEDs indicating their health.

NEC 2020 requires surge protection on all dwellings, so many homeowners have whole-home surge protection already installed. Surge protection on the HVAC unit can still be added as an extra layer, which provides better protection for the HVAC system specifically. HVAC surge protection works at the condenser.

DITEK's KoolGuard2 (KG2) is a voltage monitor that works on single-phase equipment under 40 continuous amps. It cuts power if the power exceeds or dips too far below the typical voltage, and then it restores power after three minutes. It also does not require programming, but it has a few best practices, such as reducing lead length to improve the clamping voltage and keeping protected and unprotected wires in separate conduits. Ground must also be within code have low enough impedance to redirect the surges effectively; the resistance can only be measured properly with a megohmmeter or clamp meter. DITEK also has three-phase surge protection for commercial equipment and has options for BAS systems.

Learn more about DITEK's products and DITEK University at https://www.diteksurgeprotection.com/.

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Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

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