Generac Generator Questions From a Guy Who's Made the Mistakes So You Don't Have To

Real Questions About Generac Generators (Answered by Someone Who's Paid the Stupid Tax)

So you're looking into a Generac generator. Maybe you're comparing models, or you've heard the name and want to know if it's actually worth the hype. This isn't going to be a fluffy overview. I've been handling generator orders for about six years now—started in 2019 as a junior guy making rookie mistakes, and somewhere along the way became the person others come to for the nitty-gritty.

Below are the questions I actually get asked by dealers, homeowners doing their own research, and sometimes other installers who are in a hurry and skip the manual (we've all been there). I'll give you the honest answers, including where I've personally messed up.

1. Is the Generac Generator 2200 good for camping or just emergency backup?

This is the most common question I get about that specific model. The Generac Generator 2200—the GP2200i, specifically—is a portable inverter generator. It's actually pretty versatile. I've seen guys run their RV AC units with it (carefully), and I've seen it power a fridge, some lights, and a phone charger during a blackout.

Honestly, it shines in a hybrid use case. It's quiet enough for camping (seriously, you can have a conversation next to it) and efficient enough to stretch a tank of gas for 10+ hours at 25% load. But here's the catch—or rather, here's what I learned the hard way in 2021: it's not designed to run a whole house. I had a customer try to backfeed his panel with the 2200 (note to self: always ask about their setup upfront). The thing tripped its breaker the second the well pump kicked on. He was furious. I learned: low wattage means low tolerance for surge loads.

2. The Generac vs Kohler generator comparison—which is actually more reliable?

Ah, the classic. I get this question at least twice a week. Confession: I used to default to Generac because we're a dealership. But after a few messy service calls, I started tracking failures. This was around Q3 2023. I built a rough spreadsheet of callbacks over 18 months.

The short answer? Both are solid. But they have different philosophies. Generac tends to be more aggressive with new technology (like the WiFi module for remote monitoring), while Kohler tends to be more conservative with their engines. I've seen Generac units suffer from controller glitches on early firmware versions. I've also seen a Kohler unit sit for 3 years without running and fire right up. That said, when a Generac works—and it usually does—the monitoring features are way better for the end user. Most buyers focus on engine specs and completely miss the reliability of the control board and the availability of local service. That's the real decider. If your local dealer only services one brand, your choice is made for you.

3. How do I size a standby generator? What size for a 3,000 sq ft home?

This is where I made my most expensive mistake. In my first year (2019), I confidently told a customer a 20kW unit would handle their 3,000 sq ft house. I used a rule of thumb I found online. It did not handle it. The AC unit started, the electric oven was on, someone hit the microwave— and the generator brown out. The customer called me, furious. It was a Saturday afternoon.

Here's the correct method (which I now use for every quote): you need a load calculation. For a typical 3,000 sq ft home with central AC (4-ton), electric range, well pump, and the usual lights and fridge, you're looking at a 22kW to 24kW unit. The 20kW might work if you're strict about load shedding, but honestly, leave the buffer. The extra $800 for the 24kW (at the time of writing this, January 2025) is cheap insurance against a blackout where you can't run the AC. The difference was way bigger than I expected in terms of startup surge.

4. Do I need a solar battery charger maintainer for my portable generator?

This sounds like a niche question, but it's actually something a lot of people overlook. If you have a portable generator (even a small one like the 2200) that sits in your garage or shed, the battery can die. A solar battery charger maintainer is a great idea, but maybe not for the reason you think.

Most buyers focus on the generator starting, and completely miss the battery maintenance. A standard trickle charger works fine if you have an outlet. But if you store the generator away from power, a cheap 5-watt solar panel that connects to the battery terminals will keep it topped off. I had a generator fail during a storm in September 2022 because the battery was dead. It was my own backup. $120 wasted on a service call, plus I had no power for 8 hours (ugh). I learned: the battery is the most common failure point for a stored generator. A solar maintainer is basically a 'set and forget' solution.

5. Can you compare the Honda EB12D diesel generator to a Generac portable?

This is a specific ask. The Honda EB12D diesel generator is a commercial-grade, 12kW unit. It's built like a tank. It's designed for job sites and continuous heavy use. Comparing it to a standard Generac portable generator (like the GP series) is like comparing a pickup truck to a cargo van—they serve different purposes.

The Honda EB12D is diesel (fuel is less volatile for storage), it's incredibly fuel-efficient, and it will run for thousands of hours. But it's also loud (85 dB), heavy (500+ lbs), and expensive ($5,000+). The Generac portable is usually gasoline, cheaper, lighter, and quieter. If you need a generator for a construction crew that runs 10 hours a day, the Honda EB12D wins, no contest. If you need emergency backup for your home that you can move around, get the Generac. The whole 'Honda is always better' thinking comes from an era when Honda was the only reliable option. That's changed. Generac portables are perfectly fine for home use.

6. How do I know if I have a good spark plug vs bad spark plug in my generator?

This is a 'I should have known that' moment for me. A bad spark plug is the most common reason a portable generator won't start or runs rough. I once ordered 50 spark plugs for a fleet of rental generators (checked them myself, approved it, processed it). We caught the error when the first unit refused to start. They didn't even fit. $450 wasted, credibility damaged, lesson learned: always check the model number.

Here's how to tell the difference:

• Good Spark Plug: Electrode is a light tan or grey color. No significant wear on the center electrode. The gap matches the specification (usually 0.028-0.031 inches for small engines).
• Bad Spark Plug: Black, sooty, or oily deposit (means it's running rich). White or blistered (running too hot—maybe a lean condition). The electrode is worn down, or the gap is too wide. If the porcelain is cracked, it's toast. Throw it away.

I check the plug on any used generator I'm going to sell or work on. It solves 90% of starting issues. Seriously.