Jet pump problem

Thanks,

Maybe you can give us some more info as to the pump model number and manufacturer, including the horsepower and the well data (total depth, water level and diameter).

Was the jet package and piping replaced at the same time as the pump? (Or did you simply replace the pump and not the package?).

The most common causes (assuming the jet package and pump are rated for your well depth and pump) are:

1) a partially plugged nozzle or venturi in your jet package. This can happen over time due to mineralization or scale build up.

Last Christmas eve I helped a fellow over the phone who had a very similar problem. He swore that it couldn't be a plugged nozzle venturi. Finally he pulled the piping and the package and had his son DRIVE IT TO THE FACTORY to prove that it wasn't the jet package. We found the nozzle, which was supposed to have a .290 inch opening plugged with minerals and scale so that the opening was less than 1/8". We cleaned it out for him and he re-installed it. The pump worked fine and his wife was able to make their 20 some dinner guests happy. We suggested that he change the twin drop pipes since they were probably going to loose more scale and plug the nozzle again. He decided not to. Guess what, a month later it happened again. He relaced the pipes.

2) A sand hole in one of the chamlers of the jet package.

3) a leak in the SUCTION pipe. the suction pipe is usually the larger of the two pipes in a twin pipe deep well jet (ejector/educer, etc) system. In a driven well point the leathers or seals could be leaking.

4) an improperly adjusted reguator valve. For most jet pump designs, the regulator should be adjusted AFTER INITIAL PRIMING, by backing out the adjustment until maximum flow is acheived. This will happen just before the system looses prime while backing out the regualtor screw. Screw the adjustment in a partial turn and re-prime. Technically, it's a little more complicated than this, but this guide will work. Each jet package is designed to operate at a specific back pressure to properly activate the nozzle/venturi. This back pressure depends on the well depth (water depth) and the pump and package design.

I have worked for a pump manufacturer for 25 years troubleshooting jet pumps installations. Most deep well jet problems can be tied down to an incorrect jet specification for the well, a plugged nozzle/venturi in the jet package or a leaky suction pipe. A leaky shaft seal can also allow air into the system without showing a drip. This behaves like a leaky suction pipe.

Feel free to e-mail me with the jet pump model number and manufacturer name. Jet pumps are really fairly simple machines and can be made to run well if selected and maintained properly.

P.S. the air pressure in the tank must be set (with the tank empty of water) at 2 PSI less than the cut in pressure of the switch.

In other pump news... i have a rental property with a submersable pump that kicks on everytime you draw any water. i checked the surge tank pressure and got alot of water from the air valve. i plan on replacing the tank. it looks straight forward?

thanks

My literature may be outdated. You should consult your local Flotec dealer (probably a Sears store) to get the latest performance charts and part numbers.

A sticky foot valve can restrict the flow and change performance. It can also lead to tank leak downs/short cycling and loss of prime.

P.S. no, I do not work for Flo-Tec. I do work for one of their competitors located in north central Ohio.

thanks, i was going to buy the impovement package fp4800-00 tomorrow.
the store actually said that what they had was fp4800-01?
do i understand you to say that the improvement packages are set for a water depth and that the water depth would be the distance from the foot valve back up to the water surface?
this pump has two pipes into a 4" casing.
i plan on replacing the foot valve and piping while i have it pulled.

jeff

You need to know what the distance of the top of the well to the level of the water is when the system has demand placed on it. This is because the static level - when the pump isn't operating, is usually higher than when the well has demand placed on it.

For instance, your jet package may be set at 90 foot from the top in a 110 feet deep well - BUT the actual water level may be 60 feet from the top. The pump works to "lift" the water from 60 feet, not 90 feet - or 110 feet. The work is being done from the "pumping water level", not the static water level, or the jet package level or the total well depth.

To make it simple, you may have a 200' deep well. The package may be set at 150 feet down. The water level may be 50 feet from the top. The work is only being done from 50 feet down. As water is drawn out of the well, the well level MAY drop to say 80 feet. The pump would be performing work from 80 feet then. the package should be selected for this distance.

This requires a knowledge of the well recovery charactersitics - usually documented during a "pump down test" when the well was drilled. It can also be measured with a depth sounder on older wells. Two readings are taken - static with no demand, then the depth after the well has been pumped for a known amount of time at a known flow rate.

Without this information, it is best to select the jet package for its actual depth setting.

Good luck..

It is straightforward. Just make sure the air pressure is correct in the tank. That 2 psi differential is important. Good luck.

You didn't say how deep your pumping nor if your pump is rated for that depth. Lets assume it is. If not there's your first problem.

I would say you have a suction line leak if you have air bubbles in the water. If no bubbles, then a check valve leak or a leak in the orifice jet.

T_Bone