My trusty 16 year-old Jacuzzi Magnum pump has finally died when I opened the pool today. Seems like the bearings seized-up since the pump would not spin initially. I was able to free it up, but now the pump is v-e-r-y noisy.
Here are my pool's details:
- 20x40 - 8' deep end/3.5' shallow end with 2'x2' cut corners (approximately 32,500 gallons)
- Suction Side: Two(2) Corner Skimmers; Main Drain in Deep End
- Returns (three separate return lines each with valves to control flow on/off):
- Two (2) Corner Returns & Paramount Floor Circulation (2 floor jets). These returns alternate & are not active @same time.
- Two (2) Hydrojets in 8' Stairs
- Four (4) Hydrojets in 2-Person Spa Seat
- Polaris 380 Cleaner w/separate Booster Pump
- GoldLine SWG (T-40)
- 1-1/2" plumbing on all suction lines/returns back to the equipment pad.
- Pump is approx 10 feet from the pool's corner -- longest pipe run would be about 70 feet (10 feet to pool + 20 feet along short side + 40 feet along long side of pool to farthest corner return.
- Pump is approx 12-18 inches above the pool's water surface.
- Pressure gauge reads about 12psi after backwashing the filter (last season).
No plans to add any future water features.
Magnum provided good flow with all returns open -- clear water & no algae blooms with 8 hours of runtime per day. When using the spa seat, I usually close-down the other 2 return lines and set the muli-port valve on 'whirlpool' which bypasses the filter media (currently sand but plan to change out the filter to a cartridge model @same time as replacing pump).
The existing pump is a 1HP (wired for 220V/draws 7.0 amps) and has served well. I'm leaning towards a 2-speed replacement pump so that I can operate @low speeds most of the time & save some electricity.
Looking @Pentair dual-speed models: WFDS 3/4/6 or WFDS 24/26/28. I checked 'pool school' for an explanation of uprated and full-rated pumps. The current-draw specs appear to be the same for pairs of these models (i.e., WFDS 4 and WFDS 26 have the same current draw @both high and low speeds), so is there any difference in performance?
That question aside, which of the Pentairs listed above would be a good-fit replacement for the Jacuzzi Magnum? I used the worksheet on Hayward's site to calculate TDH and am getting 38 feet TDH, but not sure I calc'd it correctly. Unfortunately I don't know and can't find the specs on the Magnum.
Any recommendations on a replacement pump?
Thanks in advance,