I recently bought a house with my first pool. This forum and Pool School have been great in helping me figure things out. I am estimating my pool is about 25,000 gal, with a spa that overflows to the pool and solar heat on the top of a two story roof. I currently have a Hayward RS1000 main pump and a second pump for the spa. The main pump has started cutting out after running an hour or so,probably overheating. I called the home warranty people, and they sent a pool guy out to look at it. When he arrived, it had just shut off. He said the pump needs to be replaced. He said the home warranty will cover me for replacing the motor with a "like kind" or they can give me a cash payment instead, which I could then apply to a variable speed pump. I am in Southern California where the electric rates are high, so the cost savings of the variable speed pump is appealing. Since I have a Jandy control system, he said the best way to go would be with a Jandy ePump, and the 1.5 HP would probably do the job. The payout is not great ($250), but the local utility has a $200 rebate that would also help. He quoted around $1100 for the new pump.
My wife then called another pool guy for a second opinion. This guy said that with the solar on the roof, we would have to run the pump at high speed anyway and we would never see enough energy savings to make it worth while. So do you think he is right? The first guy thought we could still run at a slower speed with the solar on. Never having a pool before, I don't know how often the solar is on in the summer. If it is on constantly and I need to keep the pump on high speed, then I won't save anything except during the winter when the solar won't heat the water enough anyway. If the solar only needs to be on for a short time every day, then the pump could drop to a lower speed the rest of the day and save me money.
Second question. I love the waterfall between the spa and the pool. With a variable speed pump, could I set a mode where the pump sucks from the pool and returns all water tothe spa, using the minimum pump speed to get decent flow, and have a lower cost way to run the waterfall?