Jet Pump FAQ s (Frequently Asked Questions)
Q. What does “jet” mean in the term “jet pump”?
A. Inside the nose of a shallow well jet pump there is a nozzle and venturi pair. The nozzle blows water through the venturi which creates a pressure differential. It’s this pressure differential that actually helps the pump build pressure. It’s kind of the same physics principal used in a jet engine.
Q. What’s the difference between a “shallow” and a “deep” or “convertible” jet pump?
A. A shallow well jet pump can pull water from a maximum of 25’ depth-to-water. Note that it may be less in higher altitudes. In the mountains it could be as little as 18’ to 20’ A deep well jet pump can pull water from much deeper (as deep as 80’ to 100’ depending upon model and horsepower).
A shallow well jet pump has the nozzle & venturi of the jet system built into the nose of the pump. In a deep well jet pump setup, the nozzle & venturi are put into an ejector package or “jet kit” that gets placed down in the well. In this type of setup there are two pipes connecting the pump to the ejector package. One pipe pulls the water up (suction) while the other pipe pushes some water down (drive) to circulate water through the nozzle and venturi. Water moving through that nozzle & venturi makes a pressure differential that helps bring the water up to the pump.
Q. What’s the difference between “deep well” jet pumps and “convertible” jet pumps?
A. In the case of ours, no difference. We use those two terms interchangeably. They are often called convertible because they can be set up as either shallow or deep – they can be “converted’ between the two. In a shallow well setup an ejector kit is bolted to the nose of the pump. For deep well the kit is put down the well.
Q. How can I figure out my depth-to-water?
A. You will have to get access to the top of your well. Open it up and drop down a fishing line with a bobber and weight at the bottom. When you no longer feel the weight on the line, it is floating. Measure how much line you have dropped down the well and you’ll know your depth-to-water. If your pump is not located right near the top of the well, be sure to add any additional height from the top of the well up to the pump.
Q. Is it possible for my depth-to-water to change?
A. Yes. Some wells can be affected by drought conditions or periods of excessive rains. The normal depth-to-water can change in such cases.
Also, some wells are low-producing. This means that the ground water comes in and fills the well slowly. When your pump pulls water out of the well, it’s possible that it is pulling water out faster than the ground is putting it in. In such cases, the depth-to-water will drop while the pump is pulling water out. If the water surface falls more than 25’ down in such conditions, it is possible that a shallow well pump will not be able to pull the water up. It’s also possible that when the level drops, it may drop below your pump’s suction pipe. If this happens, it is possible that the pump could lose prime.
Q. I already had a different brand of deep well pump in my well. Now I bought yours. Can I reuse my old jet package to work with your pump?
A. In probably about 85%-90% of the time the answer is ‘No’. The nozzle & venturi in a jet package are carefully engineered to match the flow rate of a specific pump. Brand A’s ejector package was not built to work with Brand B’s flow rate. That is also why it’s important to read the ejector package instructions and set the package up correctly for your specific horsepower of pump.
Q. Can I use a jet pump to pull water out of a well, lake, or river for my sprinkler system?
A. Yes. Jet pumps make excellent pumps for small sprinkler systems. You will need to choose a pump that will put out about the same amount of water as your sprinkler system requires. If your sprinkler system requires more than the jet pump can supply but less than a sprinkler pump needs to put out, you could split your system into fairly closely-matched zones. Then choose a jet pump that matches the requirements of one zone.
Q. What size or horsepower of pump do I need?
A. In general, higher horsepower pumps put out more water (the GPM flow rate is higher). Different models of jet pump are designed differently. IN GENERAL, a ½ HP pump can provide water to a small house with one bathroom and just a couple people. If you have a 2nd bathroom that might be used at the same time as the first, or if your household might run the laundry at the same time as the shower, then going with higher horsepower is going to provide the extra water your household will need. In cases of a house with multiple bathrooms, multiple people, and the possibility a sprinkler system and laundry might be running, then you probably need to go with one of the 1 HP models.
Q. Is there a problem with choosing a pump that is too high in horsepower? Why don’t I just get the 1 HP model right away?
A. The biggest considerations here are two-fold: Your electric bill will be higher; and your pressure tank needs to be large enough to avoid problems of rapid cycling. We recommend you use a pressure tank that is large enough so that every time the pump runs, it can run for a minimum of 1 minute, preferably 2 minutes. If you have a pump that puts out 10 GPM (gallons per minute) then we recommend a tank that has 20 gallons of drawdown.
Q. Why does frequent-cycling hurt the pump?
A. When an AC motor starts, it draws higher current than when it’s just running. That high surge also builds a lot of heat inside the motor. We want the pump to be able to do the work it needs to and then shut off. We want it to be off long enough so that it can completely cool off. If it has to start again before it’s completely cooled off, the motor is going to be that much hotter. Heat shortens the life of electric motors.
Q. What size generator do I need to run this pump?
A. You need to know the amp draw of the pump and multiply that by the voltage to get the watt usage of the pump. Example: Pump draws 5 amps on 115 volts. 5amps x 115volts = 575 watts.
We also need to consider the fact that an AC motor can draw three to five times its regular amp draw for about ½ second when it starts up. So to run our example pump, we need a generator that can supply a startup surge of at least 2875 watts (575 x 5) and can continue to supply the 575 watts as the pump runs.
Keep in mind this is accurate if the pump is the ONLY thing the generator is going to supply power for. If you also want to run lights, etc. then that needs to be added to the generator size.
Q. How do I register the warranty on my new pump?
A. We do not ask you to register the warranty. Your receipt is your proof-of-purchase. Keep the receipt safe. If anything happens and the warranty comes into play, your receipt is the proof of warranty eligibility.
Q. Where do I find the model number and date of manufacture on my pump?
A. The pump’s info label on the pump will have the model number and date code on it. The date code is usually a combination of letters and numbers.
Q. Where can I get repair parts for my pump, or accessories I might need?
A. Parts listed in the owners’ manual can be ordered directly through the store where you bought your pump; or can be ordered directly through us. In most cases, the store is able to special-order the parts (they won’t stock them) and sell you the parts for less than you would pay by ordering through the factory. Also, they usually do not charge shipping charges (we do). It is best to talk to someone at the store’s “Special Orders” desk. Have our toll-free number and the part numbers you need with you. If the person at the store does not know how to order parts, please have them call us while you are there. If ordering directly from us, you would normally receive your order in 7-10 business days. Expedited processing and shipping is available at additional cost. We accept MasterCard, Visa, and American Express (not Discover).
Q. Can I leave the pump right out in the rain and sun?
A. The pump motor is considered to be “drip-proof” but not weather-proof. You need to protect the pump from rain and other water, but still need to allow for air to be able to circulate around the motor. You cannot just put the pump in a big box unless there is a lot of ventilation. Usually, we recommend a sort of lean-to over the pump. Two boards that meet at the top above the pump will keep the rain off but still allow for good air flow.
Q. Do I need to use a check valve or foot valve with this pump?
A. Some jet pumps have a built-in check valve and do not require a second one. For the rest, it is recommended that you do use a check valve or foot valve in order to maintain the prime in the pump between uses. If none is present you would need to prime the pump every time you use it. The check valve should be installed in the suction side piping as close to the source of water as possible. It should not be installed within 2’ of the pump’s inlet, or anywhere on the discharge side of the pump. A foot valve functions just like a check valve plus has a strainer on it. It goes on the end of the suction line in the water.
Q. What voltage do these pumps need?
A. Most of the ½ HP pumps are set to run on 115 volts only. Most of the ¾ HP and 1 HP pumps are switchable – they can run on 230v or 115v. The motor has a switch in it to set the running voltage.
Q. Can I run the pump at a higher pressure than what they are set up for from the factory?
A. The pressure switch attached to the pump is what controls the range of pressure in which the pump will run. The switch can be adjusted for different pressures. It is very important that you not adjust the pressure switch to a pressure that is higher than the pump is capable of reaching. Call customer support for details.
Q. You make these pumps in cast iron and plastic. Which one is better?
A. We make both kinds because there is a demand for both kinds. The internals of both type of pump (as well as most of our competition’s pumps) are made of thermoplastic parts. The case is only there to hold the pump together and protect it. The cast iron may be a bit stronger in case you have your pump in an area where it could get jostled or hit by something. More important than the type of material the body is made of, is to choose the pump that will perform best in your application.
Q. Do I need to have a pressure gauge on my pump or system?
A. The pressure gauge is like a speedometer on a car. The car will run fine without it but you don’t know how fast you’re going. Likewise, the pump system will run fine without a gauge, but you have no way to know what pressure is in the system. In most cases, that’s fine. But the gauge can come in handy if you ever have to diagnose a problem..
Q. Do I need a pressure relief valve in my water system?
A. We recommend it. The relief valve will pop open if the system pressure rises too high because of some kind of equipment failure. It will release the excess pressure in a controlled way instead of what could happen if something in your water system were to fail suddenly at high pressure.
Q. What kind of pump do I need to pull water out of a reservoir tank?
A. Treat the tank just like a well (if it’s buried). If the pump is no higher than 25’ above the bottom of the tank, use a shallow well jet pump. If it’s further down, use a convertible deep well jet pump. If the tank is above ground and the pump will be next to it, use a shallow well jet pump. Note that when pulling water from a tank we recommend replacing the factory-installed pressure switch with one that includes a “low pressure cut-off” This can help protect the pump in case the supply tank runs out of water.
Q. Water comes to my pump on its own from an artesian well or a raised tank. What pump do I need?
A. You will use a shallow well jet pump. It’s performance will be a little better than we advertise since it doesn’t have to work as hard lifting the water up. Note that when pulling water from a tank we recommend replacing the factory-installed pressure switch with one that includes a “low pressure cut-off” This can help protect the pump in case the supply tank runs out of water.
Q. Can I use a jet pump to boost the water pressure in my house or sprinkler system? I need more pressure than what I currently have.
A. A jet pump can be used as a pressure booster, with a couple of limitations in mind. First, the overall pressure that the pump will see must be considered. This is the total of the incoming pressure plus the pressure the pump will add to that. For most thermoplastic jet pumps that total pressure cannot exceed about 70 psi (each pump may be different). Thermoplastic jet pumps are not really recommended for boost applications. For most cast iron pumps, the total pressure cannot exceed about 100 psi. These are maximums. You don’t want to constantly run a pump at its maximum so you should include some buffer if considering this. The second thing to consider is the pump cycling too much. Pumps like to run, and they like to be off. They do not like to be on/off/on/off, etc. If used in a booster application where the water itself can be turned on and off a lot, it is best to include a pressure tank in the application. Call our customer support dept. for details.