20 Most Recent Grundfos JPS4 1 HP Pressure Booster Pump Questions & Answers

There are several possibilities here. All involve water pressure. The first is that you have a water leak between the pump and where the water is going to. The second is that the pump is not getting enough water to it so it is sucking air well as water in an attempt to give you water perssure. This could be caused by not having an inline "one way" valve on your supply line just before the pump ($30.00). The third involves two little screws on the control where your electical connection is. These two screws control the high and low pressure settings of your pump. If your high setting is too high the pump will simply keep running trying to do the impossible, If there is not enough difference between the high and low setting the pump will also keep on. running. Another possibility is that the pump has had debris (sand, dirt, mud, etc) sucked through it and has damaged either the housing or more likely the impeller that spins the water creating the pressure.Ther is also an internal seal that can be damaged by debris. The final possibility is that the pressure control unit with the two little screws I mentioned earlier has failed and is deffective. Most importantly if the pump is running hot please stop using it! You are at risk of fire and possibly the loss of your home and loved ones. Grundfos pumps can be serviced by a professional technician, Parts are readily available and not extremely expensive. I would not recommend doing it youself if it is the pump.as some specialty tools may be involved depending on the problem. You will become frustrated very quickly. A fast solution is to buy one of the cheap plastic pumps ($169.00) made in China. They are amazing for the price and will run with no problems for years if your water is free of debris. Fixing your Grundfos may run you the same amount and you maybe without a pump for a week or more depending on the technicians work load.I am not saying "Don't fix your Grundfos" but you don't need to be in a panic about it either.

normally they have a) gasket + b) O-ring open and replace it ,remember use teflon for to avoid and help leak too.God bless you

It sounds like you have a bad pressure switch. I would also check the pre-charge pressure in the expansion tank. This needs to be 2lbs less then the "cut-in" pressure of the switch IE: 30-50 switch 28lbs air in pressure tank.RJH2O

Sounds like it could be a blown capacitor in the motor. Disconnect from the power supply and remove the capacitor - it is usually situated undet the terminal box cover- examine it for leakage or distortion and replace it if necessary.

contacts are bad short in motor start winding replace motor

It has been awhile since I have installed this pump but I think the blue is neutral and grey is hot. Thank you.

There was possibly some damage done to the pump while it was operating dry and it in now not able to deliver the required flow of water. Pumps wear very quickly when allowed to run dry, even for a short time.

I was ready to pass your question and go to the next person because you said it was making a clicking, and I could not relate or diagnose that type of sound for that kind of pump. Thank God I decided to read to the end where you said rattling sound. that is what you should have said in the beginning.
1st, did you replace the pump cartridge or the whole pump unit? 2nd, is the pump in a different oriented position than the original pump position? The inner cartridge floats inside the pump as it rotates and if it is in an oriented position that allows it to bounce (to & frow) it will make this rattle sound; not serious but can be annoying. It is was a replacement cartridge, perhaps the new gasket and the old gasket are in place, thus allowing too much space for the cartridge and it therfore moves too much and rattles. Or, if it was replaced as a whole new unit. there is a problem with it that you should not be responsible for, except for the positioning orientation. Finally, if there is still too much air in the system, the air bubbles will jossle the cartridge untill you get rid (bleed ou ) the remaining air. Goodluck<Macgivor

Most of these style knock off in a counterclockwise direction. The impeller is usually threaded onto the shaft that way. A small brass drift and hammer should move it easily.

Hi,
There are two things that can happen to cause this...

First, check that the contacts in the pressure switch are not welded together...sometimes they arc and the heat welds the contacts and keeps the power on...
The other problem is that sometimes dirt or corrosion builds up over the hole where the pressure tubing hooks up to the pump... or the tubing it's self gets plugged with dirt...then the pressure does not change to the pressure switch.. this traps water in the tubing and hold the switch on...
Take the tubing off at the pump, take out the fitting and make sure that the hole is clear...also take off the tubing at the pressure switch and make sure the fitting at the pressure switch is clear and that the tubing is clear...
Make sure to turn off the pump and relieve the pressure first or you may get an unwanted shower!!

Any questions or comments please get back to me...

heatman101

Is the air pressure in the expansion tank set properly? It should be around 35 psi. Check the side of the tank for the factory spec setting. If it is low a simple hand pump can be used and a pressure Gage to set the pressure. Also...make sure the pressure switch is set properly and there are no leaks in the system. Check for running toilets. If the problem still exist check the check valve also known as the foot valve in the well. If it is bad or not seating properly the pressure can not be maintain in the system. In turn you may need to pull the pipe from the well and check.

Hope this helps...Jim...Please leave a comment...Thanks!

http://www.kingpumps.com/PDFs/GrundfosPumps/L-MQ-TL-001.pdf

If you mean that the stainless steel pump casing is getting hot, as opposed to the motor casing, then there is a problem with the pump controller - whatever that might be, pressure switch, electronic Presscontrol type, or whatever. The cause of the pump casing heating up is sdue to the pump running for an extended period with no water passing through it. The result is the water becoming heated by agitation. This situation can arise if, for some reason the pump finds itself unable to achieve its intended cut out pressure - usual causes are blocked suction, air ingress in suction pipe or debris in the pump reducing performance.

Humming noise is usually an indication of a bad motor.

it could be the differential in pressure between the cold water from your booster pump and the hot water from your solar water heater . the cold water which feeds your solar heater is probably being reduced in pressure by a pressure reducing valve . so what you need is equal pressure on both your hot and cold water system you could install a pressure reducing valve on the pipe thart feeds your cold taps etc valve set at the same pressure as the one on the solar water heater that would give you a balanced hot and cold water system

Dependent on the size of system determines which speed the pump should be set. If in doubt set it to 3.
Does sound though as if the system is either air locked (bleed radiators) or system is badly sludged up. Is the boiler noisey or do the radiators that are working have cold spots? If so its probably sludged.
2 options: Buy a chemical cleaner from a diy store or call someone in for a system flush, which will take most of the day.

Hi and welcome to FixYa. I am Kelly
Drain the pressure tank completely. The tank is designed to have a pressurized pocket of air at the top of the tank that would allow the tank to act as an accumulator when pressurized. If the tank does not have that air bubble the pump will cycle quickly and lose pressure almost as soon as you put any demand on the pump. After you drain the tank, just reinstall the drain plug and test. It should work normally. If it does not work normally then there is an unknown water distribution leak in your plumbing.. You can eliminate house plumbing by truning off the water supply after the pump and then see if the pump still cycles. If it does then pressure is leaking back into your water source. There should be a check valve to prevent the pump from pressurizing your water supply. If the check valve has failed or some internal debris not allowing the check valve to close you will have the symptom you describe.

Thanks for choosing FixYa.

Kelly

Close the outlet valve then turn electrical switch on manual for a few seconds until any air is pushed out then open the valve and return electrical switch to automatic.

sounds like you have internal leakage therofore pressure decreases and pump cycles to regain it.
not sure what you actuating mechanism is. if its a diaphram it needs to br replaced. if its multiple pistons- your seals need replacing.

chances are that a screen is clogged and needs servicing.