[willarrington]

Is it possible to a add a pressure switch to a transfer pump that does not have one. I thought that if I hooked the switch up to the electricity source then to the pump from the switch. I would attach the switch directly to the pvc 1 inch pipe going to the house on a T outlet. Any possibility? If not the pump will just keep on running even if it does not need to. Thanks for any input.

[speedball1]

By "transfer pump" if you're referring to a booster pump the answer is yes.

. I would attach the switch directly to the pvc 1 inch pipe going to the house on a T outlet.

Unless I'm missing something the control box should attach directly to the pump body. If I'm wrong now would be a good time to correct me. Regards, Tom

[willarrington]

Yes. Northern Industrial Cast Iron Clear Water Pump — 720 GPH, 1/2 HP, 1in. | Utility Pumps | Northern Tool + Equipment
This is the product. Thanks for your help.

[speedball1]

Looking at the pump,

I would attach the switch directly to the pvc 1 inch pipe going to the house on a T outlet

I don't see a place to attach the pressure control tube. The tube would go from the pipe to the control box and the electric would go from the control box to the pump. Good luck. Tom

[willarrington]

You couldn't put the control tube on the pvc going to the house. Electric from the source - to the pressure switch - to the pump. When the pressure in the line built up, would it shut off the power to the pump. I do not know exactly how a pressure switch works, sorry about the questions. Thanks for your help.

[jlisenbe]

Will, do you have a pressure tank between the pump and the house? If not, then I would think you would not be able to use a switch. In fact, I would think you would have to have a pressure tank for the whole thing to work to begin with. Many booster pumps come with a small tank attached to the pump and the switch already in place as well.

[cheec_8548]

Hi,

Yes you can. There are basically 2 types of transfer system in the building services.
One is so call the conventional type that uses electrode sensing (placed in the receiving water tank)
another type is using pressure sensing.

There are however a couple of consideration (especially seems that you did no cater for pressure sensing system at the point you select your pump)
1) Firstly, check your application and the max no of start/stop your allowable as you might need to have pressure vessels to bring down the no. of start stop if required.
2) The duty point of the pump - as most differential pressure switch has a sensitivity (usually is 0.5bar) you have to select the duty point of the pump further to the right of the pump curve and try to cater for 1 bar or at least 0.8 bar (depending on your pressure switch specs)to the next point on the left. In this case you have a cut in and a cut out point for on the pump curve. Otherwise your pump will have a high tendency of running out of curve. Ask whether this duty point selected fits your required flow and head at the discharge point? Otherwise you have to change a pump.
3) Place the pressure switch 10X diameter away from the last pump discharge. This is to have a more accurate pressure sensing effect as well as reduce unnecessary water turbulence in the piping.
4) The pressure isolation fitting at the discharge point. Be it pumping to a tap or water tank you will need a fitting that shut off the flow when demand is no longer required.

The pressure sensing transfer are will known for it's 2 advantage.

1) Pressure switch wiring to the pumps are house just side by side. Wiring cost are much cheaper compared to running level sensing electrodes all the way to the water tank.
2) Water hammering for high static pumping are eliminated.

Disadvantage will be for pumping up a high static head the pressure of the entire system is increase dramatically and therefore class for pipes and fittings are increase as well contributing to a higher cost.Also pressure vessels are most of the time required which require more space and money.

Thanks.

Mel

[jlisenbe]

This one is two years old. But hang around. There will be plenty of need for your observations in the future. Welcome aboard.

What is your background?

[cheec_8548]

Again.. Thanks for highlighting anyway.
I am working as a pump specialist for building services.

Nice to know you.