Pressure Switch advices

[Valveman]

The only way that type pump would shut off when no water is coming is if it had a "Presscontrol" thing on top of it. Those things have a flow switch that shuts off the pump when there is no flow. I don't see one in your picture, so it doesn't have dry run protection. Also, they use those presscontrol things on low head pumps that can't build enough pressure to work with a normal pressure switch. You need a good jet pump that can build enough pressure, and a low pressure cut off switch to protect the pump from running dry. Those type pumps and the presscontrol things are made to sell and not last very long, which is exactly why the pump companies push them over something like a Cycle Stop Valve that will make pumps last 30+ years.

 

[danny.h]

The only way that type pump would shut off when no water is coming is if it had a "Presscontrol" thing on top of it. Those things have a flow switch that shuts off the pump when there is no flow. I don't see one in your picture, so it doesn't have dry run protection. Also, they use those presscontrol things on low head pumps that can't build enough pressure to work with a normal pressure switch. You need a good jet pump that can build enough pressure, and a low pressure cut off switch to protect the pump from running dry. Those type pumps and the presscontrol things are made to sell and not last very long, which is exactly why the pump companies push them over something like a Cycle Stop Valve that will make pumps last 30+ years.

okay good to know, just scary that technical support in Grundfos said, there is dry run protection, they suppose to be in the lead of pumps around the world. but I found it odd also there was, because the pump is 11 month old and already broke and the plummer who open the pump said, it looks like it have run without water.

 

[Sponsor]

 

[Reach4]

I don't see one in your picture, so it doesn't have dry run protection.

I posted the picture. Danny's pump may look different. Danny, unless I missed the picture you posted, post a picture.

 

[Valveman]

okay good to know, just scary that technical support in Grundfos said, there is dry run protection, they suppose to be in the lead of pumps around the world. but I found it odd also there was, because the pump is 11 month old and already broke and the plummer who open the pump said, it looks like it have run without water.

Just because they are the "leaders" in pumps around the world doesn't mean they are trying to help you out. They opted not to use Cycle Stop Valves almost 30 years ago, because Cycle Stop Valves make pumps last longer and use smaller pressure tanks. These pump companies prefer you use the "presscontrol" thing or a variable speed controller so the pump won't last very long. They know if you use a Cycle Stop Valve instead, your pump will last 30+ years, and they don't like that. They are "leaders" in pumps around the world because they sell so many, not because they make pumps to last.

 

[danny.h]

I insert a picture of the pump, also in specification I can see, it doesnt have press comtrol, but it does have termo fuse, so if the motor runs without water, the motor gets very hot and will shut down, or I am mistaken?

 

[Valveman]

The motor is air cooled and will not get hot even if you run out of water. When you have been out of water for a few minutes the impeller gets hot, melts down, the pump locks up, and then the motor will get hot and trip the thermal overload. But by the time a thermal overload trips it is way too late to save the pump. A low pressure cut off switch is the least expensive way to protect from dry run, the Cycle Sensor is best, but you need something.

 

[danny.h]

The motor is air cooled and will not get hot even if you run out of water. When you have been out of water for a few minutes the impeller gets hot, melts down, the pump locks up, and then the motor will get hot and trip the thermal overload. But by the time a thermal overload trips it is way too late to save the pump. A low pressure cut off switch is the least expensive way to protect from dry run, the Cycle Sensor is best, but you need something.

Okay I guess my plummer dont know enough, he just said looks like it has run without water, but its not burned, it still runs, but cant do a pressure more than 30 psi I thought it was something else, but I had a extra motor and put that on, and vupti it got to 50 psi, so I know its the motor.

 

[Valveman]

Again, running without water will hurt the pump but not the motor. If your motor is the problem is was probably caused by too much cycling on and off.

 

[Reach4]

Okay I guess my plummer dont know enough, he just said looks like it has run without water, but its not burned, it still runs, but cant do a pressure more than 30 psi

30 psi with what pressure input? I think this is being used as a pressure booster for city water, if I understood correctly.

A pressure gauge that shows both vacuum and pressure would be good on the input.

 

[danny.h]

30 psi with what pressure input? I think this is being used as a pressure booster for city water, if I understood correctly.

A pressure gauge that shows both vacuum and pressure would be good on the input.

input was 60 psi it was being used for a pressure booster, because the pressure of the city water wasnt good at all.

 

[Reach4]

input was 60 psi it was being used for a pressure booster, because the pressure of the city water wasnt good at all.

I have to think the pressure drops a lot when you use much water, because otherwise you would not have felt the need for a booster.

A gauge like this would be nice on the input.