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kiwibrewer
06-25-2014, 01:05 AM
Hi,

I recently installed two new pumps to replace older worn models in our brewery. Both the new and old pumps came from the same factory and are to the same spec.

The CIP pump I replaced seems to be running with a higher pressure than the older one (however this old one was also leaking and sounded terrible), but the HLT pump I put in yesterday is not providing the same pressure I had on my old model.

Could I have wired it in wrong, or do you think it is a defect with the pump itself.

I brought six new pumps total, just putting them in one at a time as our brewing schedule allows. Hoping to avoid any install errors on the rest.

Any thoughts appreciated.

Cheers,
Fraser

Starcat
06-25-2014, 06:22 AM
There is a lot about your setup that is not being provided information wise.
Your use of the underspeed term seems to be a matter that you perceive the new one is not feeling like the former.
A new pump with an intact seal member will definitely develop more pressure than one that is " sucking air."
Outright miswiring an electric motor will most often destroy it. The exception is say wiring a 115-208V motor for 208 and putting it on 115v in which case it may run for a time.
Replacing a 3450 RPM motor with a 1725 would be a problem.
Using motors rated for a different voltage frequency can be a problem. 50 to 60hz. is a notable RPM difference.
A pump specialist may be able to help you sort out these matters if he is given all the necessary data off your pumps and motors as well as the applied voltage etc.

gitchegumee
06-25-2014, 05:04 PM
Or it is running backwards. Easy mistake to make. Otherwise, identical pumps perform identically. Something else is the issue. Pay careful attention to wiring diagram, or get a professional. Check motor direction! Good luck.

kiwibrewer
06-30-2014, 12:06 AM
Hey guys, sorry for the lack of info in the initial post, had to school myself on pumps/motors a little. So the pump is a centrifugal type running on a 3 phase induction motor. I went over the wiring again, and it turned out I had two wires out of phase. Swapped them over and it's working just fine now.

Cheers for the help, appreciate it!

Fraser

Starcat
06-30-2014, 06:34 AM
Hey guys, sorry for the lack of info in the initial post, had to school myself on pumps/motors a little. So the pump is a centrifugal type running on a 3 phase induction motor. I went over the wiring again, and it turned out I had two wires out of phase. Swapped them over and it's working just fine now.

Cheers for the help, appreciate it!

Fraser

This sounds like as Phillip has mentioned above that you were running backwards.
2 things that must be checked on any motor startup of any kind are:
1. Rotation - which must be verified immediately, usually easily done by looking at the output shaft or the fan
2. Current which must be known shortly after startup as read with an Ammeter and verified to be " in range " with the nameplate