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VFD application for small Community Water System

VFD application for small Community Water System

VFD application for small Community Water System

(OP)
I am designing a community water supply for a small community (about 30 homes).  In the past, we have used two or more wells with hydropneumatic storage, and put all the controls (and water treatment, if necessary) in a pumphouse.  Recently, the pumphouse part has become an expensive part of the project (it depends on the construction style chosen, of course).  I am wondering about using a simple VFD, with smaller tanks, and then put the controls in a small enclosure (without water treatment).  

I have looked at the residential VFD's, like the Grundfos SQE
and the Goulds Balanced Flow.  However, I want the reliability of two wells, and I don't think that those residential controllers work in multiple pump applications.

I have also looked at the Aquavar CPC.  That looks cool.  I think I can use one or two of these, using a small pressure tank and small enclosure, and meet my requirements.

Can anyone give me advice about this?  How does the price of these controllers compare with a larger pressure tank?  

In the past, I have sized the tank to minimize start/stops of the pump motor.  How does the VFD controller protect the pump motor from excessive starts/stops?

RE: VFD application for small Community Water System

The Aquavar CPC works very well. The built in logic is better than tryin to set-up a PLC/VFD system. If one well can be used to supply the demand it gets very simple, just alternate with a time clock. The fact that the CPC is a VFD means that many more starts per hour are possible.

I don't know about costs for "larg" tanks.

It is VERY important that the load side reactor be installed.

Are you disenfecting?

Steve Wagner

RE: VFD application for small Community Water System

(OP)
Thanks for replying - I think I put this question in the wrong forum.  

We probably will add Cl and F.  In the past, we have used diaphragm or peristaltic pumps for chemical addition.  

I think LMI and Stenner both have VFD-type pumps available to match flowrate, but do you have experience with this setup?  Can I really get a chemical feed pump that will feed at the proper rate (and adjust quickly) matching the aquavar CPC's varying flow?

RE: VFD application for small Community Water System

Was curious to see what you decided to do and what you found out.  We have been encountering the same issues with the increase expense of pressure vessels. I was personally concerned about leakage in systems at night forcing the pump to run all night and consume alot of power/gal pumped.  

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