Hello everyone. Great forum. I am relatively new here and was hoping people might be able to give me some guidance.

I purchased a house about 5 years ago that has a 25,000 gallon pool. I am looking to upgrade some of the equipment and have a few questions.

The pool has one skimmer. There is a drain in the deep end of the pool that only works through one of those float valves (not sure if that is the correct name for it) in the skimmer. I.e. this drain does not appear to be hooked up to anything except when the float valve is configured to cause the skimmer to pull water from this drain. There is also a spa attached to the pool that has a drain.

At the equipment pad, there are two 1.5" or 2" inch pipes feeding the pump. Although not certain, as best as I can tell one pipe is from the skimmer and one pipe is from the drain in the spa. The system currently uses a Tagleus Pentair sand filter (probably relatively old, although I have removed the sand and confirmed that everything still appears to be intact internally). There was a very old gas heater hooked up, which I removed from the plumbing loop because the heater does not work at all. On the output side of the filter, there are three 1.5" lines going back to the pool. As best as I can tell, one goes to the pool and one goes to the spa jets. The third was marked with an "X." Not exactly sure what that one does, although it appears that it may somehow balance water between the pool and an additional set of jets in the spa.

The current pump is a single speed Hayward Max-Flo rated 1.5HP, with a service factor of 1. There is also a booster pump on the output side of the filter for a Hayward Viper pool cleaner. That pump is rated .75 HP.

At minimum, judging by the noise it is making, I believe I need a new main pump. I have read a good number of the threads comparing the Intelliflo pumps with two speed pumps, and without intending to offend anyone, I have to say that I am leaning in the direction of a two speed Whisper-flo pump. Having said that, I live in CA, so it is possible that my high utility rates (probably about $.12 per KWH, on average) and long swimming season may mean that a variable speed may be more likely to make sense. So, please do not hesitate to tell me why you think my decision to use a two speed pump may be a mistake. I am sure the Intelliflo's are great pumps, and it sounds like there may be a good consensus that they are more efficient at low speeds. But, in light of the information I have read, I am coming down in the camp of being unsure that the performance/flexibility of the Intelliflo justifies the price premium. In particular, my reaction, at this point at least, is that a properly sized two speed pump may be the way to go. So, I am looking for help in deciding whether to go with a 1HP or 1.5HP two speed pump.

The skimmer is probably about 60 ft from the equipment pad; the spa is probably 10-15 feet closer to the equipment pad; and the jets in the pool are maybe another 10-15 feet even closer to the equipment pad.

My wife and I honestly don't care about the strength of the spa jets. In particular, we are placing a higher priority on energy costs savings than performance of the spa jets. It is possible that the reason the pool owner originally went with a 1.5HP pump was to have strong spa jets. When I look at the performance specs for the 1HP 2 speed Whisper-flo's, however, it looks like a 1HP Whisperflo should be sufficient to clean the pool. So, my first question is whether or not you think I may be wrong in that conclusion. In considering my questions, it makes sense to assume that each of the plumbing lines that I mention above has at least 2-3 90 degree elbows, although I obviously don't know what is underground.

I'd like to use my new main pump to drive my viper pool cleaner and get rid of the booster pump. Any reason that may not make sense?

I am also thinking that I'd like to add a solar heater. I am in a great location for solar, although I'd be interested if people feel that solar is not cost effective e.g. because I'd have to run my pump on high for most of the day to drive water through it. The solar panels would be on the top of a single story house that is probably 35-40 feet from the equipment pad. I am not sure if the low speed on the Whisperflo will be enough to drive the water through the solar heating system. Do you think solar heat makes sense for my circumstance and, if so, what one or more pump(s) would you recommend? Would I be better off with a gas heater or heat pump? Again, not too worried about the spa heat at this point (e.g. don't care if I have a heater to heat up the spa quickly). Rather, we only want to warm the pool water to a more comfortable temp during, at the beginning and end of, the swimming season.

The pool doesn't see a high bathing load, and I don't expect that to change within the next 5 years.

In any event, look forward to any input and guidance. Thanks in advance for any help. Please let me know if there is additional info I can provide to help evaluate my situation.

Regards,

Mike