I'm planning on replacing my loud Waterco 2hp (max) pump with a quieter (and more efficient) pump. However I am almost ready to hook up and start using my 160' solar heating array .
QUESTION #1: Will a 3/4 hp pump be enough to get up to top and prime solar array 2 stories (25') above pool + 110' of mixed 1.5"-2" piping?
QUESTION #2: will 2-speed pump work on low once solar array is primed?
QUESTION #3: My WaterCo T450 sand filter says "Max flow=35 gal/min, max pressure=21 psi". Given most pumps have GPM > 60 I'm curious if
My initial guesses based on reading Hydraulics 101 topic:
#1: My initial guess is to buy a 3/4 HP (full rated) WhisperFlo 2-speed pump. This way I'll have enough suction to keep my Polaris Ranger vacuum moving on it's own when cleaning.
#2: I'm guessing 3/4 hp on low speed will keep enough pressure once solar array is fully primed… but I have no way to test this and calculating would be brutally tedious.
#3: I haven't pulled out a hose and 5gal bucket to measure my current GPM and I'm overloaded with other projects (such as plumbing up to the new solar array). I suspect after head losses I'm not pushing more than 35gal/min… or perhaps I am and that's why whenever I backwash I never see clear water no matter how long I run (because zeobrite is being blown out with water by current 2HP max pump ).
Plumbing specs & details:
Pool is a 2007 Diamond Star 54" Oval AG vinyl pool with original pump and filter kit + custom piping for solar array.
12' wide X 24' long X 48" (4') Deep (even though pool is 54" high)
7,700 gallons per www.poolcalculator.com
Plumbing: ~138' total
14' 1.5" cheap flex hose
6' 1.5" spa flex hose (tigerflex?) from hard piping to pool return
8' 2" bypass route (core hard piping)
110' 2" solar heater route
15' up to roof base
15' over + 4' overhang
30' across parallel array + up to top of
20' back to pump corner
5' misc pipe routing
=110' total length
=138' total piping (118' 2" + 20' 1.5")
Waterco AquaMite Series pump
110v 1ph. (Phase), 10.5A run - 12A max
110*10.5=1,155 Watts (1.16 kW)
1.155*1.38=1.5939 hp run (service load)
110*12=1,320 Watts (1.32 kW)
1.320*1.38=1.8216 hp max (peak load)
FYI: At $0.10 per kWh this is 12 cents to 18 cents per hour to run.
Model 2402200DU (2HP)
Max pressure: 21 psi
Nominal Diameter: 18"
Filtration area: 1,733 sq ft
Max flow: 35 gal/min
Filter media: 165 lbs (75 lbs ZeoBrite)
160 sq ft total surface (8' x 20')
1 4'x20' array (unknown mfg), 1.5" Male threaded manifold
2 2'x20' SolarBear array, 1" female threaded manifold
Base height from pool: 15'
Top height from pool: 19'
Head calculations based on Hydraulics 101:
Static Head for solar array = 25' (near pool bottom to top of pergola roof)
FYI: Pump should handle 2x static head to prime quickly.
Return Dynamic Head = 2.31 * Filter PSI
Clean filter typically runs 13 PSI with current 2hp max pump
2.31 * 13=30.03
Pipe dynamic head not calculated
~17 90' elbows
(yes, I've designed and built all my own plumbing and this is one area my inexperience probably shows)
20' 1.5" cheap flex hose (came with AG pool kit)
6' skimmer to pump
Someday I might get around to replacing cheap flex hose… if I need to.
140' 2.0" s40 pipe
=55' head not including pipe dynamic head
Thanks in advance for any answers, thoughts, or experience with similar or partially related configurations!