Hansberger Refrigeration Blog: Your AC Repair Resource

How to Make Sure Your HVAC System Hasn’t Been Compromised by a Power Outage

HVAC power-outage issues can go beyond just the interruption of comfortable temperatures inside your home. When the electricity goes out, furnaces and air conditioners typically shut down automatically. Electrical components in the furnace include control circuits, the gas valve, and the igniter, while the A/C compressor and the system blower fan are also dependent on utility power. Unless your home incorporates a backup generator, you’ll be without heating or cooling until grid power is restored.

From Outage to Surge

However, these events can cause more than just discomfort and annoyance. Power outages are strongly associated with subsequent power surges. Very often, high-voltage spikes occur when power is restored following an outage. This instability originates externally on the local utility grid and may affect a wide area connected to the grid. Because a power surge often sends voltage far above 220 volts into the wiring, virtually any appliance or device — including most HVAC systems — connected to the home’s electrical circuits may be at risk of severe damage.

Protecting Your HVAC Investment

Because furnace and central A/C units are hardwired into the home’s circuits, protective measures such as simply unplugging the components during a power outage aren’t feasible. However, installing permanent surge protectors provide protection from HVAC power-outage issues in two ways:

  • Whole-house surge protectors are installed at the home’s main electrical panel. These devices continuously sense grid voltage for surges and will interrupt the power into the home before unsafe voltage enters household circuits and damages electronics. A whole-house surge protector offers protection, for all devices in the house, from power surges that originate externally.
  • Additional protection can be added by installing a surge protector engineered specifically to protect the central A/C compressor. As the single most expensive component in your HVAC system, any damage to the sensitive compressor can be extremely costly. These dedicated units typically install at the power cutoff box that controls electrical power to the outdoor unit of the central A/C, which includes the compressor.

For more information about protection from HVAC power-outage issues, including transient power surges, contact the professionals at Hansberger Refrigeration and Electric Company.