Replace motor or the entire pump?

[Technikal]

I'm looking to move to dual speed in order to cut energy costs.

I have a full rated 1.5hp Hayward Tristar. I have no idea how old the pump is as it was with the house when we bought it. The pool was built in 1994 so it could potentially be that old. It works fine though - no leaks or cracks or issues that I can see.

I use an SWG, but no automation to worry about. There are no pool features to run. I use a Polaris 280 with booster pump (fwiw - my equipment pad is located lower than the pool, so the pipes are constantly 'primed' if that makes any difference). I figure with this setup, I could run the pump in low speed for all normal operations, so no need for a complex dual speed timer, or variable speed setup. I'd just put a manual switch in to change speeds whenever needed.

It looks like putting in a 2 speed motor with the requisite seals, switches and whatnot would be around $450. Complete replacement pumps are about $250 more. I'd do the install myself either way.

Is there any reason to go with a complete new pump? Any 'gotchas' that could be hiding in my current pump that are going to be costly to repair beyond the motor and seals? Is the Tristar going to continue to be supported - it doesn't seem to get very much coverage vs Hayward's other pumps...

Thanks!

 

[Bama Rambler]

If the pump casing is in good shape; and you can get the bolts out, and remove the impeller, then just replacing the motor is the less expensive route. However, if you can't get some of the casing bolts out, or you can't get the impeller off and you wind up damaging the casing, impeller, or backplate in the process, you'll spend more for parts than a new pump will cost.

It's really your call, because you know what shape the pump is in.
If you wanted to be sure before you buy anything, you could try to take the pump apart and then if something gave you problems you could just go the new pump route at that point.

 

[PoolGate]

Before you make your final decision I would check with your local utility for pump rebates as they can be very substantial ($400 here!). In any case, I would opt for an entirely new pump and not mess with repairing a pump you are not sure of the age.

 

[Technikal]

Thanks for the feedback. I was planning to go with a complete new pump, but when I started comparing flow charts, I realized that my current Tristar pump is a 'high head' pump. It's putting out significantly more GPM's than most other 1.5-2.0 HP pumps I was comparing it with. I don't know why the pool has a high head pump - the pad isn't super far from the pool, there's minimal elevation difference, and the plumbing - at least what I can see above ground - is not complex. But, erring on the side of caution, I decided I'd stick with what I have and just swap out motors. Even better, the replacement motor is more efficient than most of the 2 speed complete pumps I looked at (1.6 amps vs 3.0 amps running on low speed).

I have the motor now and am waiting for the gasket kit and switch to be delivered. Looking forward to a more efficient and quieter pool!

 

[Technikal]

That was pretty easy. Took about 2 hours start-to-finish. The new pump is much, much quieter on slow speed, and the strainers are still pulling in water pretty well. If my calculations are correct, I should see the cost per hour of running the pump drop by 84% (old pump ran at 10 amps, new pump runs at 1.6 amps on low). Given my SWG was primary driver of my pump run time, and that I should get adequate water turnover for filtering running the pump on low for the time I need for the SWG in swim season, I should see actual savings not too far off that. It should pay for itself in 5 months.

 

[needsajet]

Sounds like a win-win!

Great to reduce the noise and cost, and by changing the motor there was no cost or time for plumbing as well.