Most business owners plan for power outages: what to do with the inventory, how long the food stays safe, who to call. But outages aren't the part that kills compressors and control boards most often. It's the power around the outage — the surges, sags, and split-second flickers when the grid hiccups and comes back. That's the threat almost nobody plans for.
What "power quality" actually means
Your refrigeration equipment expects clean, steady voltage: a consistent 115 or 208/230 volts on every cycle, every day. In the real world, voltage jumps and dips constantly — a fraction of a second here, a few volts there. Most of the time the equipment rides through it. But the big events don't come alone, and refrigeration equipment is one of the worst places in your building to take a hit:
- Surges (voltage spikes) can fry control boards, sensors, and thermostats instantly.
- Sags (voltage dips) starve the compressor of the power it needs to start. A compressor trying to start on low voltage draws excessive current and overheats its windings.
- Rapid on-off cycling — when power flickers back and forth during a storm — forces the compressor to attempt a restart under pressure, with no time to equalize. That's one of the fastest ways to kill a compressor.
The board that dies "for no reason" three weeks after a storm often died during the storm.
Why commercial kitchens and food businesses are at higher risk
Greater Boston's commercial buildings stack the deck against your equipment:
- Older buildings and shared panels — many restaurants and markets run in older buildings where refrigeration shares electrical service with everything else: HVAC, ovens, lighting. Large loads switching on and off create constant small dips and spikes.
- Utility switching and construction nearby — grid work, new construction in the neighborhood, and seasonal storm restoration all produce surges on the lines feeding your building.
- Weather — lightning doesn't have to strike your building. A strike on a nearby line or transformer sends a surge down the wire straight into your equipment.
- Your own equipment — large motors and HVAC units cycling on and off create surges inside your own building. Your refrigeration is downstream of all of it.
Warning signs power quality may already be hurting you
- Circuit breakers on refrigeration units trip and need frequent resetting
- Control boards or thermostats have been replaced more than once in a year or two
- After storms, a unit "won't start" or the compressor hums but never kicks in
- Lights in the building visibly dim or brighten when large equipment cycles
- Digital controllers show error codes or lose their programming after a power event
Any one of these is worth a conversation with a technician before the next big event does real damage.
What actually protects your equipment
Not all protection is equal — and some common "protection" is close to useless:
- Whole-facility surge protection (installed at the electrical panel) is the real line of defense. It clamps down surges for the entire building, including every piece of refrigeration on the circuit. This is the single highest-value upgrade most owners can make.
- Phase monitors for three-phase equipment — walk-ins and ice machines on three-phase power can be destroyed by a lost or reversed phase, which is more common than most owners realize. A phase monitor shuts the compressor down before it runs on damaged power.
- Dedicated circuits — refrigeration equipment should not share circuits with unrelated loads. If your reach-in or prep table is tripping breakers that also feed other equipment, the wiring layout itself is part of the problem.
- What not to rely on — a cheap power strip from an office supply store is not surge protection for a compressor. It isn't rated for the loads involved and gives a false sense of security.
What to do after a storm or power event
When the lights have flickered, the grid has been restored, or you arrive to find the building dark:
- Check temperatures first — before touching anything, verify what's in the danger zone and what isn't.
- Listen when power returns — compressors should start smoothly. Humming without starting, repeated clicking, or tripped breakers are stop-and-call signals.
- Check digital controllers — confirm setpoints survived the event; controllers that lost their programming can run at the wrong temperature silently.
- Don't keep resetting tripped breakers — a breaker that trips twice is telling you something. Call for service instead of forcing the equipment to start against a fault.
Small investment, expensive failure
A surge protection device and a proper electrical checkup cost a fraction of one compressor replacement — and a fraction of one lost weekend of inventory. Power quality is invisible until the day it isn't. Protect the equipment that protects your product.
If you're not sure your building's power is clean, or your equipment has been acting strangely after storms, call Frostline Commercial Refrigeration at (857) 666-8916. We'll check the equipment, flag the risks, and make sure a flicker of the lights doesn't become the end of a compressor.