Downsizing Pump

[Glennr]

I have an inground pool that is less than 10000 gallons with a small spa. The pump is a Pentair Whisperflow WF-28. Someone replaced the motor with a Champion 2HP 1.10 SF. I have no idea, but I doubt the replacement motor is energy efficient. The pump is doubling my electric bill each month. I am paying about $220.00 while the pooless neighbors are spending less than $100.00 and I have no unusual energy uses.
I was thinking about downsizing my pump to see if that would help since I think that 2 HP 1.10 SF is too big for my small pool although I don't know how to factor in the spa. Would going to a 1.5 or even a 1 energy efficient pump still work in my situation and with my spa?
I realize that replacing the entire pump would be the best thing but to save money can I just replace the motor and impella

[mas985]

Spa jets usually require higher flow so a higher HP pump is required. If you like the feel of the jets, you will need to keep the same HP pump. However, you could swap the motor for a two speed so that you could run on low speed when not using the spa. The WF-28 has a sister pump the WFDS-28 which is the same wet end but a two speed motor. You would need to get a replacement motor for the WFDS-28 and seal kit for the swap.

[Me...]

I would agree with Mas. I have seen many setups as I imagine yours to be. A spa with maybe 4 concrete jets which are roughly sized at 1/2hp each. You would need the 2hp for them but as you suspect you don't need that for normal filtration for a pool that size.

2hp on all the time with a trickle going to the spa, which overflows back into the pool. You switch a 3-way valve to isolate the spa when you use it. As Mas says a 2hp 2-speed motor would save you a TON of money. Hi speed for the jets and maybe to backwash your filter. I hope if its sand its a big one! Or 2 even.

From what you say, the replacement motor has the same specs as the original, or close enough you would not notice a large difference in cost to operate.

[poolpumpguy]

I HERE ABOUT THIS ALL THE TIME AND IT MAKES ME SOOO MAD YOU ARE PAYING FOR THAT SPA TO RUN EVERY DAY ! THIS IS CRAZY , GET RID OF THAT PUMP . BUY A STA RITE DURA GLAS OR A HAYWARD SUPER 2 . 3/4 OR 1 HP COMPLETE PUMP.( THESE ARE THE TWO PUMPS I WOULD USE.IN ORDER.) YOU WILL NOTICE A LARGE DROP ON POWER COSTS .
LOOK ON CRAIGSLIST FOR YOUR LOCAL POOL PUMP MOTOR REPAIR GUY. I'M IN FLORIDA AND I DO NOT SHIP PUMPS, REMEMBER NOT TO USE THREAD TAPE ON PLASTIC POOL PUMP AND PRIME THE PUMP BEFORE YOU TURN IT ON AFTER REPAIRS .. YOUR POOL PUMP MOTOR REPAIR GUY IN SUNNY LONGWOOD FLORIDA.. SORRY ABOUT ALL CAPS BUT I'M GET'N OLD AND THERE EASY FOR ME TO SEE .J