Replace motor or entire pump?

[concretegardenstx]

Hi gang,

I have a 2HP Pentair Whisperflo WF-8, and also a Pentair Tagelus sand filter I installed last year after my cartridge filter cracked. The pvc pipe coming out from the filter blew off last year. It was suggested in a previous post to me that the motor might be too much for the filter, and there was a lot of vibration in that part of the pvc. It has also been suggested I don't need a 2HP motor, so I'm here looking for advice. I have done a lot of reading but I'm not sure if I can find a straight answer.

I have an attached spa, but we never use it. I don't know what other information would be helpful. Can I use a lower HP motor, do I need a variable speed motor or a 2 speed motor? Can I replace the motor without replacing the pump, or do I need to replace the whole combo? What specs do I need for a replacement motor? I am hesitant to contact someone like INYOpools for advice because I have that feeling in the back of my mind they are going to sell me an entire motor/pump when maybe I just need a motor. Though I don't have a budget, I'm trying to be as cost effective as possible.

I appreciate any advice you can give me!

Edit: I also have a fountain inside of the spa, but I won't cry if I can't use that either

 

[kadavis]

https://www.amazon.com/EcoTech-Variable-Speed-Swimming-Replacement/dp/B00YSZ5RDS, this would be a VS Motor only that would fit your needs. Otherwise the Pentair Intelliflo VS pump would be a complete replacement that is the same footprint as a Whisperflo.

 

[mas985]

Can I use a lower HP motor, do I need a variable speed motor or a 2 speed motor?

If you lower the THP of the motor without changing the impeller, it will overload the motor so to downsize you would need to change both or the entire pump.

The TA 60 is too small for that pump. But if you think you are ever going to use the spa in the future, I would swap out the motor for a two speed motor and up size the filter.

 

[concretegardenstx]

If you lower the THP of the motor without changing the impeller, it will overload the motor so to downsize you would need to change both or the entire pump.

The TA 60 is too small for that pump. But if you think you are ever going to use the spa in the future, I would swap out the motor for a two speed motor and up size the filter.

How do you know that the TA 60 is too small for that pump? What would be the correct size? I've been trying to look all over TFP to get this information, and Google, but haven't had much luck.

Thank you!

 

[mas985]

The TA 60 has a design flow rate of 60 GPM. A WFE-8 will deliver about 88 GPM on decent plumbing. A TA100 would be big enough to handle that flow full time.

However, that doesn't mean that the TA60 wouldn't operate sufficiently. Sand filters are quite robust so it just might mean that it won't filter the water as good as it should (i.e. the higher flow rate might push debris all the way through the filter). If you can run the filter primarily on low speed, then it should work fine. If you only run the pump on high speed for the spa, then it probably wouldn't matter that much.

 

[concretegardenstx]

The TA 60 has a design flow rate of 60 GPM. A WFE-8 will deliver about 88 GPM on decent plumbing. A TA100 would be big enough to handle that flow full time.

However, that doesn't mean that the TA60 wouldn't operate sufficiently. Sand filters are quite robust so it just might mean that it won't filter the water as good as it should (i.e. the higher flow rate might push debris all the way through the filter). If you can run the filter primarily on low speed, then it should work fine. If you only run the pump on high speed for the spa, then it probably wouldn't matter that much.

I'd rather downsize the pump/motor, as the electric bills get ridiculously high and I probably don't need that much power. I am trying to read through and understand the links in your sig, but while I am learning that, would I be looking at getting a 1HP to go with my existing filter? Also, does brand matter? For example, I have a Pentair filter, would it matter if I had a Hayward pump?

Thank you again for your help and patience.

 

[mas985]

You would reduce energy costs a lot more by going with a two speed pump running on low speed than you would by just reducing a single speed pump's THP. Or you can do both. But remember that if you reduce the motor size, you have to change out the impeller too.

Also brand does not matter.