Sizing for Your Refrigerator and Freezer — Keeping Food Cold
Last verified: September 2026
How to size backup power for the fridge and freezer without overbuying: plan for the compressor's surge, lean on how long food stays cold, and let a smaller unit protect both by taking turns. Rather talk it through? My number is (330) 200-8042.
Sizing for the Fridge and Freezer, at a Glance
The fridge and freezer are the first things most folks want to keep running — and they're more forgiving than they look. Inside each is a compressor motor that surges when it starts, so you size for that jolt, not just the steady draw. But because they hold their cold (a fridge keeps food safe about 4 hours, a full freezer about 48), you can cycle the power between them and other loads, so a smaller unit protects both by taking turns. This guide covers the surge, the food-safety clock, and the take-turns trick, with a printable version up top.
Common Questions
1 Do I have to power the fridge and freezer at the same time?
Usually not. Because both hold their cold with the door shut, you can cycle the generator between them — running one at a time — so a smaller unit can protect both. An unplugged box simply coasts on the cold inside.
2 Why do I have to size for more than the fridge's steady draw?
The compressor is a motor, so it needs a brief starting surge several times its running watts to kick on — again and again as it cycles. A unit sized only to the steady draw may not start it. See our running-watts-versus-starting-watts guide.
3 How long does food stay safe without power?
Kept closed: a refrigerator keeps food safe about 4 hours, a full freezer about 48 hours (about 24 if half full). An appliance thermometer in each box tells you the real temperature.
4 The power was out — how do I know what to keep?
Discard perishables (meat, poultry, fish, eggs, leftovers) held above 40 degrees F for over 4 hours. When in doubt, throw it out — and never taste food to check, since some germs leave no smell or taste.
5 Is a chest freezer really better in an outage?
It holds its cold longer. Open a chest and the cold air stays down in the box; open an upright and it spills out the front. In a long outage, a chest freezer buys you extra hours of safe food.
6 Should I use a battery or a generator for the fridge?
A battery or power station can often carry a fridge for a while if its watts clear the surge and its watt-hours last; a generator suits longer runs and bigger lists. See our guide on watts versus watt-hours.
Would You Rather I Just Help?
Protecting your food shouldn't be a guessing game. I'll help you read your fridge and freezer nameplates, size for the surge, set up an easy take-turns plan, and know what to keep or toss after an outage — with nothing to sell you. $99 flat for a visit, 30-day come-back-free.
Would you rather I just do this for you?
No shame in it — plenty of folks would rather hand it off, and that's what I'm here for. I'll come to your home, set it up right, and make sure it's working before I leave. Flat $99 per visit — no jargon, no upsell, and every visit is 30-day come-back-free.
Not a hardware job? I can often fix it remotely for $49 — a secure screen-share, up to 2 hours, that you watch the whole time and can end whenever (included free for $39/mo Support Plan members, and it counts toward the $99 if it turns out I need to come out).