When you depend on an alternative energy source to power your off-the-grid home, chances are you have a backup system in addition to your main off grid electricity system with solar panels, windmill, or water power.
If you’re like many families off the grid – including us, your backup system involves one or more generators. So when your main system is down or drained and your generator won’t start, it’s pretty nerve-wracking.
Especially if you’re new to living with a generator, and trying to maintain and run it in extremely cold conditions.
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But in the winter months, we get as little as 4 ½ hours of daylight each day.
So we depend on our generators. They charge the batteries that keep our lights on, our appliances running, and our propane-powered boiler heating our in-floor heating lines.
(Okay, we have a huge Roby wood stove as well for heat).
We’ve learned that sometimes, generators don’t start on the first try. Especially if it's -30 Celsius or colder outdoors.
And we've discovered that before panicking (or calling a repair person), there are a few things to try. Here are eight things to check when your home generator won't start.
What Do I Do When My Generator Won't Start?
Whether it's a diesel or a gasoline home generator, one of the simplest reasons it might not start is a lack of fuel. So check your tank first thing. Getting your generator started could be as easy as topping up your tank.
2. Check for Clogged Carburetor
Old fuel gets thick and sticky as it ages. And if like us, you don't run your generator very often in the summer, thick sticky fuel could clog your carburetor. And a clogged carburetor could be the reason you can't get your generator going.
So take a look at your fuel. If it looks kind of murky or if it’s separated, siphon it out (safely) and add fresh fuel. Or try Dan's trick and add a dash of fuel stabilizer.
3. Test the Battery
Now if you're a total newbie to generators, inverters, and battery banks (like me), you might not realize that some generators with electric starts have batteries.
Just like your car battery, these batteries can get old and lose energy. Kind of like we do.
Check your generator's battery with a multimeter. If your battery is dead, try jumping it.
In our case, Dan will just drive his pickup to the front of the generator shed and boost the generator battery from his truck battery.
Sometimes, fuel filters get clogged. And that's what they're there for - to prevent debris from traveling from the fuel line into the generator.
Our generator shed houses our two 10 kW Lombardini diesel generators. Our diesel tank sits outside the shed, and the fuel line feeds through the shed wall and to both generators.
4. Check The Fuel Filter/Water Separator
Another reason your generator might not start is if there's water in your fuel.
Our generators have a fuel filter/water separator sight glass attached that allows you to see if there's water in the fuel line. Even better, it also has a release valve. So if there is water in our diesel tank, Dan can drain it off.
5. Try Your Preheat Again
It's hard to get equipment going when the temperatures drop down to the -30 Celsius range. And that includes generators.
Sometimes a generator won't start because we haven't given it enough preheat time. Usually, I'll turn the ignition key to the preheat setting and start counting: one Mississippi, two Mississippi, three Mississippi.
Somewhere around "30 Mississippi", the light turns from orange to green, and I know the glow plugs are warm enough to start the generator. But in the middle of winter, I sometimes get up to "50 Mississippi" before the genny is good to go.
When you're depending on generators in a cold-weather climate, it's really important to have a well-insulated generator shed, and ideally, some sort of heater.
One option is to leave your heater running continuously at a low temperature. Or you could do what our neighbor does and fire up a portable heater an hour or so before running your generator.
Our generator shed has a 10k BTU propane wall heater. We find that if the outdoor temperature is as low as -19 Celsius (that's about -2 Fahrenheit) our shed heats up quickly just from the generator itself running.
And because our shed is so well insulated, it's still warm 10 hours later when we go out to run the generator again. We also leave the generator shed propped open for ventilation to avoid carbon monoxide building up inside.
P.S. We replaced the glow plugs on our main generator this past winter, which really reduced the preheat time.
6. Blockage in the Fuel Tank or Line
If there's some kind of blockage in your fuel tank or line (like ice or dirt), the fuel might not even make it to your generator. And then it won't start. So it's a good idea to check for blockages.
Also check your line for clogs, twisted sections, or leaks. And consider keeping a spare fuel line on hand, especially if you live far from town.
7. Take a Look at Your Glow Plugs/Spark Plugs
(Note: diesel generators have glow plugs, and gasoline generators have spark plugs. These plugs ignite a spark that starts the generator.)
How are your plugs? Are they worn or cracked? Maybe the electrodes are eroded or damaged.
If so, use a spark plug tester -- it may be that faulty spark plugs are behind your generator not starting.
Using a spark plug tester is easy. Because if you see a spark when you use the tester, your plugs are fine. No spark? Time for new plugs.
8. Clean The Air Filter
Find your generator’s air filter. Just how dirty is it? If it's clogged badly enough, it could stop your home generator from starting.
If your air filter's really grimy with dust, you could try cleaning it. Whack it against a wall, counter, or even the floor to shake loose the worst of the dirt.
If the dirt won’t budge, or if it’s worn through or torn, it’s possible your generator won’t start until you get a new air filter. Check your generator owner's manual for air filter specifications to make sure you buy one that will fit your own generator.
Note: In an absolute emergency, it IS, in fact, possible to run a generator without an air filter. Although it is definitely not recommended.
Maintain Your Generator!!!
One of the best ways to improve the likelihood of your generator starting is to take good care of it. Change the oil every 100 hours. Inspect it regularly for signs of wear and tear.
As with most things, some preventative maintenance can save time, money, and hassle of calling in a qualified generator repair person.
To learn more about generators and off-grid power generation, continue reading below.