Guidance sought about a new pump

[poolcrazed]

I had no idea the selection of a new pump could be so complicated! Reading through some old threads.
Ours is 15 years old and has been a little tricky to get going the last two springs but then has worked well, but we are thinking we should get a new one before we open this year since it's so old. Otherwise it has worked well, though it's loud! But what to get? I don't want to leave it to a pool service company to decide. Your advice would be very appreciated. The pool is 17x35--about 24,000 gallons. It's a very old in-ground pool- from the 1960's. It has one line flowing in and one out. That's it. It's never super vigorous circulation but the water stays clean so apparently is good enough. Sand filter (which I backwash and rinse well but have not been doing annual cleanings on). I have a Hayward super pump, self priming model C48K2N143B1, HP, 1 RPM 3450. We do not have a heater (though sometimes I wish we did! it does not get a lot of direct sunlight so it stays pretty cool all season. I am in upstate NY.)
Thank you if you can help guide me. Getting something quieter would be wonderful.

 

[BMerrill]

Hayward Omni Tristar 950 VSP. It will pay for itself in a few years by energy savings.

 

[poolcrazed]

Yikes, that IS expensive. Our season is short and with the pump I have, I can get by with running it 8-10 hours, though I usually keep it on longer....so I think it would take a long time to make up the energy savings. Other ideas, size?

 

[Rancho Cost-a-Lotta]

Yikes, that IS expensive.

DOE regulations now require most pumps to be variable speed. Name brand pumps will be similarly priced to the Hayward. Many forum members are installing bargain brands that seem to be a good value. As short as your season is, this may be the way to go. The Calimar 1.5 and 3 hp pumps are the lowest priced. Do your research on features and warranties...

Calimar/Circupool/BD/Blue Torrent Pump - Further Reading

www.troublefreepool.com

 

[BMerrill]

My Tristar VSP runs 12 hours a day at 1550 RPM, flows 50 GPM, used 240watts.
My rate is 0.12 cents per kW. Cost 0.34 cents a day, or $10.37 a month to run.
A 1 HP non VSP pump motor runs at 3450 rpm, uses about 1725 watts = 20,700 watts for 12 hours or 20.7 amps.
Using my power rate of 0.12 cents the cost to operate the 1hp pump is $6.17 a day or $185 a month.
Using a VSP could potentially save you $175 a month. In 9 months it will pay for itself.
The TriStar has fully programable controls built in.
Yes, there are less expensive options. Your Hayward gave you 15 years of service. Sometimes bargains are not really bargains when you consider the service life.

 

[rootusrootus]

I'm skeptical that 1550 to 3450 RPM is 7x the power consumption (more typically, 3x the power for 2x the RPM is in the right ballpark). Or that the runtimes are going to be the same. The VSP will be more efficient per GPM, yes, but you run longer to compensate for the lower flow. You will still win in the end, but expecting to save $185/month is a pipe dream. I would guess anyone who's actually burning 20 kWh a day just for the pool pump *knows* it. I'm a power hog and that would be fully a third of my typical daily usage for the whole house.

 

[Rancho Cost-a-Lotta]

I'm skeptical that 1550 to 3450 RPM is 7x the power consumption (more typically, 3x the power for 2x the RPM is in the right ballpark).

I think your estimates are off. Here's my pump display...



Here's a chart that one of our guides put together a few years ago...

 

[Mdragger88]

My in laws just bought a calimar 3hp vsp from pool supply unlimited. There was an option for a 3rd party extended warranty at purchase so they chose that for some peace of mind. I believe it’s also an option to add an assurion lawn & garden ext. warranty when purchasing the black & decker, blue torrent or other brands on Amazon.

 

[SJPoe]

Depending where you are (or where you CAN be for delivery purposes...) rebates of up to $500 are also available, which might make your sticker-shock a little less.

The 3HP Calimar pumps from PoolSupplyUnlimited are $520. They also have an option for a 3 year warranty from Extend for $99 - makes a 3HP VSP pump about $600.
Based on my Hayward Superpump 1.5HP running 12+ hours a day, plus a Utility Company rebate of $75, I'll pretty much cover the cost this season in electricity alone, and I'm on a pretty short season.

Regardless If the pump fails outside of that 3 years, I'll just replace it. I'd need to replace it 3 times to equal the cost of one 'premium' pump.

Now I just need to get around to actually installing it...

 

[rootusrootus]

I think your estimates are off. Here's my pump display...

It could just be that VSPs are like that, but it suggests a big divergence between pump RPM and flow. My 2-speed pump has a 3x jump in power (measured with a current transformer) for a 2x RPM increase, nothing even approaching 10x. And my RPM corresponds closely to flow -- I get 16 GPM at 1725 RPM, and a bit more than 30 GPM at 3450. I would expect an efficient VSP pump to have a *closer* correlation between power and actual flow, not less (my relatively inexpensive Hayward 2-speed pump should definitely be less efficient).

There are, of course, other complicating factors that will vary by locality. E.g. My electricity cost during the day is 32 cents/kWh. My cost at night is 4 cents/kWh. I might personally not see much savings at all if I ran a VSP at a low enough flow that it had to run most of the day, instead of a higher speed pump that can turn over the entire pool within the window of time when power is cheap.

 

[BMerrill]

I'm skeptical that 1550 to 3450 RPM is 7x the power consumption (more typically, 3x the power for 2x the RPM is in the right ballpark). Or that the runtimes are going to be the same. The VSP will be more efficient per GPM, yes, but you run longer to compensate for the lower flow. You will still win in the end, but expecting to save $185/month is a pipe dream. I would guess anyone who's actually burning 20 kWh a day just for the pool pump *knows* it. I'm a power hog and that would be fully a third of my typical daily usage for the whole house.

The RPM, Watts, Flow I posted are actual readings from my system.
The power usage of a single speed 1.0 hp pump came from a thread on TFP.

Below is a complete chart of my system.
Rpms and watts used are from the controller. The flow rate is best interruption of the analog scale on the FlowVis meter.

RPM Watts Flow GPM
600 27 16
750 52 22
1000 92 35
1250 148 43
1500 240 50
1750 350 58
2000 494 65
2250 695 75
2500 932 85
2750 1230 94
3000 1594 102
3250 2050 110
3450 2418 115