If you've walked over to the sink only to find that nothing's coming out of the faucet, you're probably going to have to prime a jet pump to get things moving again. It's one of those household tasks that sounds way more technical than it actually is, but if you've never done it before, it can feel a bit overwhelming. Don't worry, though; it's basically just a fancy way of saying you need to get the air out of the system so the water can actually move.
Jet pumps are great, but they have one major flaw: they can't pump air. They need a solid column of water to create the suction necessary to pull more water from your well. If air gets into that line—whether it's from a power outage, a leak, or just the pump being off for a while—it loses its "prime." When that happens, the motor will hum and spin, but you won't get a drop of water.
Getting Your Tools Ready
Before you dive into the guts of your plumbing, you'll want to grab a few things. You don't need a massive toolbox for this, but having the right stuff on hand will save you from running back and forth to the garage.
First, you'll need a bucket of clean water. This is the most important part because you're going to use this water to fill the pump. Since your house water isn't working, you might have to grab this from a neighbor or use some bottled water you have lying around. You'll also need a pipe wrench or a large pair of pliers to get the priming plug off. Depending on how long it's been since the pump was last opened, that plug might be a bit stubborn.
I'd also suggest having some thread seal tape (Teflon tape) nearby. While you're in there, it's a good idea to refresh the seal on the plug to make sure no air leaks back in once you're done. Oh, and grab a couple of rags or towels. Things are probably going to get a little splashy.
The Step-by-Step Process
Alright, let's get into the actual work. It's not a race, so take your time and make sure you're doing each step carefully. If you rush, you might end up having to start all over again, which is the last thing anyone wants when they're already frustrated about the lack of water.
Safety First: Power Down
Before you touch anything, turn off the power to the pump. You can usually do this at the breaker box. You do not want the pump trying to kick on while you're unscrewing parts or pouring water into it. It's a safety hazard, and it can also damage the pump's internal seals if it runs dry for too long.
Locate and Remove the Prime Plug
Once the power is off, look for the priming plug. On most jet pumps, this is a small square or hex-headed bolt located right on top of the pump housing (the big metal part). Use your wrench to slowly unscrew it. You might hear a little hiss of air escaping—that's a good sign, actually, because it confirms that air was trapped in there.
Fill the Pump with Water
Now, take your bucket of water and start pouring it into the hole where the plug was. You'll want to do this slowly. If you pour too fast, you might create more air bubbles. You're looking for the water level to rise up to the very top of the opening.
Sometimes, as you pour, you'll see the water level drop suddenly. That just means the water is moving down into the suction pipe. Keep pouring until the water stays level at the top and doesn't disappear down the pipe. This part can take a few gallons, especially if you have a long run of pipe from the well to the house.
Reinstall the Plug
Once the pump housing is full, it's time to put the plug back in. This is where that Teflon tape comes in handy. Wrap a little bit around the threads of the plug to ensure a tight, airtight seal. Screw it back in by hand first to make sure you don't cross-thread it, then tighten it down with your wrench. Don't over-tighten it—you just want it snug enough that air can't get in or out.
Bringing the System Back to Life
Now that you've filled the pump, you aren't quite finished yet. There's still a bit of "cycling" that needs to happen to get the pressure back where it belongs.
Go ahead and flip the power back on. You should hear the pump start to run. Now, watch your pressure gauge. If the needle starts to climb, you're in business! However, don't be surprised if it runs for a minute and then stops without reaching full pressure.
Sometimes you have to prime a jet pump two or three times to get all the air pockets out of the line. If the pressure doesn't rise after a minute or two of the pump running, turn the power back off and repeat the filling process. It's annoying, but it's pretty common, especially with older systems or deep wells.
Bleeding the Air from the Faucets
Once the pump is running and the pressure is building, go to the faucet closest to the pump and turn it on. It's going to cough and sputter—that's just the last of the air being pushed out of the lines. Let it run until the flow is steady. Then, go through the rest of the house and do the same for every other tap. Don't forget the showerheads and the toilets!
What if it Still Won't Prime?
If you've tried the process a few times and you're still getting nothing but a dry pump, you might have a deeper issue. It's frustrating, I know, but here are a few things to check before you call in a pro.
One common culprit is a leaky foot valve. The foot valve is located at the very bottom of your well pipe; its job is to keep water from flowing backward out of the pump and back into the well. If that valve is stuck open or has a crack, the water you pour into the pump will just drain right out the bottom. If you notice that your pump housing won't stay full no matter how much water you pour in, the foot valve is likely the problem.
Another issue could be a suction leak. Even a tiny pinhole in the pipe between the well and the pump can let in enough air to break the prime. Since air is much "thinner" than water, the pump will suck in air through that hole instead of pulling water up from the well. Check your visible pipes for any damp spots or signs of corrosion.
Maintenance Tips to Prevent Future Headaches
Nobody wants to spend their Saturday afternoon trying to prime a jet pump, so a little prevention goes a long way.
First, keep an eye on your pressure gauge every now and then. If you notice the pressure is dropping slower than usual or the pump is kicking on more frequently when you aren't using much water, you might have a slow leak starting. Catching it early can save you from a total loss of prime later on.
Also, if you live in a cold climate, make sure your pump house or the area where your pump sits is well-insulated. If the water inside the pump freezes, it can crack the housing, and you'll be doing a lot more than just priming—you'll be replacing the whole unit.
Wrapping Things Up
Learning how to prime a jet pump is one of those essential "well-owner" skills. It might take a bit of patience and a couple of tries to get the hang of it, but once you do, you'll feel a lot more confident managing your own water system.
Just remember to take it slow, keep things airtight, and don't be discouraged if it takes more than one attempt to get the water flowing. Most of the time, it's just a matter of being more persistent than the air bubbles trapped in the pipes. Once you hear that steady hum and see the pressure gauge climb, you can go back to enjoying your running water and leave the bucket and wrench behind.