During a blackout, you cannot run everything, but you can run the essentials comfortably.
Yes, you can run simultaneously:
Total running wattage for above: ~2,400W. You have over 3,000W of headroom.
You can also add (one at a time):
What you CANNOT run:
When the lights go out, or when the job site needs silent, reliable energy away from the grid, few names command as much respect as Generac. For decades, the Wisconsin-based manufacturer has dominated the home standby generator market. However, in the portable space, one specific model number keeps surfacing in forums, contractor reviews, and emergency prep lists: the 5500 Generac. 5500 generac
But what exactly is the "5500 Generac"? Is it a single model, or a family of engines? More importantly, can it handle your refrigerator, sump pump, and power tools simultaneously?
In this deep-dive article, we will dissect the specifications, real-world performance, maintenance schedules, and competitive landscape of the Generac 5500-watt class generators. By the end, you will know precisely whether this mid-range workhorse belongs in your garage.
The 5500 RPM Generac uses a low oil pressure switch (normally closed). If pressure drops below ~6-8 PSI, the switch grounds the ignition, killing the engine.
The trap: Many owners bypass this switch thinking it’s "faulty" during cold starts. Never bypass it. A cold start on a 5500 RPM engine with thick oil can take 1–2 seconds to build pressure. That is fine. But if the switch trips after the engine is warm, you have a real problem (clogged filter, worn pump, low oil level).
Pro tip: Use only SAE 5W-30 or 10W-30 full synthetic. Do not use 15W-40 or straight 30W in cold climates—it will delay oil pressure buildup and trigger nuisance shutdowns. During a blackout, you cannot run everything, but
A 5500-watt generator is not a "carry-in-one-hand" device. It weighs roughly 190–210 pounds dry. Generac includes a telescoping handle and "NeverGo Flat" wheels (solid, puncture-proof rubber). This allows one person to roll it across gravel, grass, or asphalt without a hand truck.
This is the million-dollar question. With 5,500 running watts, you are in the "sweet spot" of portable power. You are not in the tiny 2,000-watt camping class, nor are you in the heavy 15,000-watt industrial class.
Scenario A: Home Backup (The "Storm Ready" setup) During a 24-hour blackout, one 5500 Generac can run:
Total: ~3,550 running watts. You have 2,000 watts to spare, but remember the well pump’s surge. As long as you don't start the vacuum cleaner while the well pump kicks on, you are golden.
Scenario B: Job Site (The Contractor’s Choice) Total running wattage for above: ~2,400W
What You CANNOT Run: You cannot run a central air conditioner (needs 6,000+ watts). You cannot run an electric water heater (4,500 watts leaves no room for lights). You cannot run two large microwaves simultaneously.
Do not just add gas and pull the cord. Follow these steps to ensure longevity.
If your 5500 RPM Generac suffers a "rod knock" or loses oil pressure completely while running, do not rebuild it. The crankshaft is likely scored beyond repair, and the block is often damaged.
Real-world cost: A new short block for a 5500 RPM Generac costs $2,200–$2,800. Add labor ($1,000+), and you are better off buying a modern 3600 RPM or inverter generator.