Is my sand filter sized right?

[TheGoose]

AO Smith

1 HP 230V B2982

http://www.aosmithmotors.com/product...69&terms=B2982

I am fairly competent when it comes to installing things like controls and motors so you don't have to think I'm gonna fry myself doing this.

I guess we can't easily post pictures but high is L1, then you have L2, and then you have A for low speed. I'm thinking that I should connect one incoming wire to A and one to L2. For full speed I install a switch between A and L1.

[PoolDoc]

Sorry, if I offended you . . . but I've worked with too many electricians who couldn't wire a DPDT switch for a 2 speed pump, for me to take anything for granted. Here's the connection drawing:



Based on that drawing, yes, can toggle between high & low, and switch speeds. Remember, that you need a 15A MOTOR or INDUCTION rated switch. And, if you place the switch external to the motor, you need to attach a warning label indicating that the switch does NOT disconnect power to the motor. Intermatic has a DPDT time clock you can use, that's not much more than an SPDT clock.

[TheGoose]

That's the picture I was going to post.

You didn't offend me, I was just trying to relay that you don't have to do the typical dummy comments like "shut off the breakers" and such. I work with pumps/motors everyday, some of which are thousands of horsepower.

Thanks for the warning about the 15 amp switch, it makes sense.

[PoolDoc]

Actually, I typically include the "DPDT" acronym as a test . If you'd reacted with a "Huh?", I would have launched the "Hire an electrician; you can't safely do this yourself" boiler plate.

However, I've learned the hard way knowledge in one area does not bleed over into a related area, for many people. I can't tell you how many graduate chemists I've dealt with who get confused by pool chemistry . . . or who find Chem_Geek just as hard to follow as I do! So, telling my you work with 1,000 HP motors doesn't tell me you know how to wire a 8A 230V motor, in a wet area, using the crappy conduit sold for residential and light commercial use! (Hint: always, ALWAYS use a wired ground!)

[TheGoose]

OK, one last question for now:

Since I was using my regular 1-HP pump at about 12-15 hours per day, what should I run this new configuration on low speed?
I'm hearing that if it will pump ~60 GPM at full speed, it will still do ~20-30 GPM at low speed, but uses way less electricity to pump at the low speed. So I'm supposed to be able to run twice as long on low as I did on high and still save money. Is this a true statement or is it more marketing? Also I've read reports both ways that it increases the efficiency of your filter since the velocity of the water is so much slower that the filter will work better.

Thanks.

[PoolDoc]

Sand filters work MUCH better at low flow, but you have to backwash at high flow.

To actually know what your flow will be, I'd need pump curves AND a detailed layout on your equipment. But 1/2 the flow for 1/5 the electricity is probably in the range.

[TheGoose]

I've got some pictures I would like to send ya or post if there's a way. I know how to do it in other forums, but I noticed you have pics disabled in this one.

[PoolDoc]

send them to poolforum@gmail.com, and I'll post them -- I'll look to see if there are problems with the permissions in this section at the same time.