Which pump for my pool?

[sheolraver]

Hi. Old pump is 1 HP, 1.65 Service Factor, 17,000 gallon in ground pool, 1.5 inch plumbing, Four 4X10 solar panels at ground level I recently installed with 2 inch plumbing to and from panels, old cartridge style filter (100 sq ft I think). Pump went out soon after panels installed. Pump lost prime and ran dry for some time, although it was working fine for several days prior. I couldn't get the pump to stop leaking so I think it's best to replace the whole thing, rather than just replace the motor portion.

If my pump uses 1.65 KwH per hour I figure I currently spend maybe $600 per year as the pump runs perhaps 3-4 hours per day average over the year. I am very happy with my water quality.

Pool store guy says that a 1/2 horsepower pump will move as much water as my very old 1.65 HP pump (15-20 years?) . Further, he says that the only pump which will work for me is a 1/2 HP pump due to the 1 1/2 inch water line. Anything larger he says is wasted because you can only suck so much water from the front of the pump.

Pool guy says he wants to talk me into variable speed pump. $1600 including installation (ouch). He says it will pay for itself fast but I don't think he realizes that I only run my pump a few hours each day and am happy with that.

Any help most appreciated!!

Bob

 

[mas985]

I couldn't get the pump to stop leaking so I think it's best to replace the whole thing, rather than just replace the motor portion.

The pump may only need a new seal kit which is < $50. have you tried replacing all the seals and gaskets?

 

[sheolraver]

At this point, the pump only runs for about 30 seconds and then it stops. I live near Sacramento.

THanks

 

[mgarf33]

If you can pull apart the motor to repair it, why would you pay $500-$1000 for someone else to install one?

I like my VS pump. Gives me more flexibility.
If I have a party with a lot of people I crank it up.
I usually run my pump 24/7.

If I'm not using it much I can dribble it down to 1600 rpm and run it for about 63¢ a day.

Regular usage at 2200 rpm costs about $1.20 a day,

full speed 3000 rpm costs about $2.50 a day.

 

[sheolraver]

If you can pull apart the motor to repair it, why would you pay $500-$1000 for someone else to install one?

I don't think the motor can be repaired. I am looking at installing a variable speed pump myself. Almost bought one just now and decided to research some more.

Current pump: (1.0HP )(1.65 SF ) (.75motor efficiency)(4hrs/day)(32cents/KWhour)=$1.58 per day.

So let's say I use mgarf's figures for his VS pump and estimating my useage (very little), it's maybe going to cost me 80 cents per day if I use a variable speed pump (averaged out over the whole year).

($1.58/day)(365)=$577 /year current pump
(.80/day)(365)=$292/year mgarf's vs pump figures modified by estimation for my smaller pool and probably lower number of swimmers.

So I potentially could save $285 bucks per year, paying for a new pump in perhaps 4 years. Starting to sound more palatable

Thanks much,

Bob

17,000gal in ground pool, currently no working pump, cartridge 100sqft filter (old and leaking), 1 skimmer and return, chemical only pool service, vinyl liner, ground level solar panels.

 

[mas985]

Being Sacramento, you probably pay a lot more as I do for electricity. If you are in tier three, you pay $0.29/kwh?

Here is an economic analysis I did for$.30/kwh. An Intelliflo is about $15/mo while a MaxFlo VS would be about $11/mo. Pretty small either way. You can download the spreadsheet from the link in my signature.

 

[sheolraver]

Holy Frijole!!!!

I certainly did not expect this degree of help!

THANK YOU!!!!!

- - - Updated - - -

Oh, and I hit tier 4 maybe half the time (3 kids, big house). We don't even run the a/c it costs so much. Big swamp cooler. Tier 3 is roughly double tier 2, and tier 4 bumps another 10% or so. The highest I paid in tier 4 last year was .35cents/kwh.

 

[mgarf33]

I just went out and looked at the display for the real #'s on my Hayward SP VS.
So, my estimate was a bit off, but the chart above looks close to what I read.
Some day I'll get around to checking the accuracy of the display panel.

Here's what I read on the display:
3000rpm - 1.289kW $3.68/day for me
2200rpm - 0.581kW $1.66/day
1600rpm - 0.261kW $0.74/day

Lucky me, I only pay 11.9¢/kWh

I don't know about other VS pumps, but I selected the rpm rates for more quiet resonant frequencies. You can barely hear it operating at 1600.
Another benefit of VS pumps.

 

[mas985]

I certainly did not expect this degree of help!

Not a big deal. The spreadsheet was setup already. I just maid a copy of it for posting.