Need Help with cistern and pressure pump

[knarans]

Is there a way to fill my cistern with a grunfos pressure pump?

I have a cistern that is filled from the well with a float switch and a Grundfos pump that supplies the house from that cistern.

I want that pump to fill a 2nd cistern that will have a pressure tank to supply the house.

How can the Grundfos be set up to turn on and off to fill the new 2nd cistern.

Thnaks for any help you can offer

 

[Valveman]

All you need is an electric fill valve on the extra cistern. When the float switch drops the pump will thing a sprinkler zone came on and will start and supply the cistern until the float switch shuts it off. With a flow control knob on the electric valve you can control how much water goes into the cistern so you are not using all the water the pump can supply or the house would have no pressure. However, when you vary the flow rate to fill a cistern of for any reason, a Cycle Stop Valve on the pump is important to keep the pump from cycling itself to death.

 

[Sponsor]

 

[knarans]

All you need is an electric fill valve on the extra cistern. When the float switch drops the pump will thing a sprinkler zone came on and will start and supply the cistern until the float switch shuts it off. With a flow control knob on the electric valve you can control how much water goes into the cistern so you are not using all the water the pump can supply or the house would have no pressure. However, when you vary the flow rate to fill a cistern of for any reason, a Cycle Stop Valve on the pump is important to keep the pump from cycling itself to death.

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Cary: Thank you for your reply. I forgot to mention that the new cistern would be gravity feed to the Grundfos pump. Will that be a problem for the vlaves that your recommend? Also I would like to replace this float switch box with a newer model. Do you have anything that would work?

 

[Valveman]

With gravity feeding the first cistern just a float valve like in a toilet is all you need to control the tank level. Then after the booster pump and Cycle Stop Valve you can use the output to fill as many other cisterns as needed, but they will need the electric solenoid valves controlled by a float switch.

 

[Valveman]

You can definitely use your Grundfos pump to fill the second cistern! You'll need to set up a separate float switch in the new cistern that triggers the pump to turn on when the water level gets low. Make sure the pump is set up to only run when needed to avoid overfilling. You might also want to consider adding a check valve to prevent water from flowing back into the pump. Overall, it's a pretty straightforward setup, but if you need more detailed instructions, it might be best to consult with a professional to ensure everything is done correctly.

You can't run wires from a float switch to the pump is the pump is already being controlled by a pressure switch/tank set up. A solenoid or float valve is the only way that would work. Also, most people come to a DIY forum because the "professionals" either don't know what they are doing, charge too much, or are not available. Calling a "professional" doesn't mean much these days as there are very few who know what they are doing. At the very least a person should educate themselves on the subject before calling a so called professional.