what if i connect 2 water pumps drain together.

[burrow]

I have 2 water pumps, PUMP 1 is a 1 hp Pump (JET PUMP) and Pump 2 is a low power ( around 300 watts) pump, what will happen if i connect pump as shown in the attatched image


Is it okay to connect as shown, or the high pressure from PUMP 2 will kill pump 1 ?

what will happen ?. Does reverse pressure has any drastic effect on pump ? .


Please throw some info about that will be the consequences when both are running and when one of them is running.

 

[BradtheRad]

The overhead tank suggests it is not pressurized. If so then both pumps should be okay working at the same time.

If pressurized then you must make certain you don't cause the pumps to force water to a pressure beyond their ratings.

 

[burrow]

Overhead tank is at a moderate height..so it does exert a good pressure on the smaller motor when run alone.

 

[BradtheRad]

I'm wondering if I've ever seen these two specs stated regarding pumps, but it's possible a pump feels a different amount of force at its inlet compared to its outlet. That is, how its internal structure bears the weight of the water.

Seems to me that a pump which is able to lift water up a 50 foot pipe (say) into its inlet...
Will be able to hold the weight of a 50 foot column of water at its outlet.

Looking at your diagram, I do not see that one pump will affect the other adversely. It appears that water will flow freely within the pipes, in response to flow from one or both pumps. Of course if there is a restriction in the pipe at the overhead tank, then a sudden jolt from one pump might be conveyed to the other pump.

I have slight experience with buying a pump. The chief spec of interest is its lifting force, as in how tall a column of water can it lift? As for its pushing force, I got the impression it is assumed that the pump will be strong enough to pressurize a closed system. Ours had a maximum pressure of 50 lbs. I was able to hold my thumb on the spigot, stopping water flow.

If you find you can hold your thumb on the pump outlet, that will give you an idea how strong the pump is.

As I think about it, there may be a spec that says, 'this pump should only be used with a non-pressurized system.'