Re: 3 HP too much for spa?
cword said:
Thanks for that info. I can actually get the 3HP whisperflo cheaper than the 2 or 2 1/2 due to overstock. Would a 3 hp pump be too much? My spa has the waterway power jets (6 of them) they use 2" flex pipe and 2 1/2" PVC pipe. My spa is 8' diameter, with spillover. Can I handle the 3hp and would it be a wise choice? Thanks agin. BTW my equiptent pad is about 40 ft. from the spa.
A 3 HP would probably be too big for your plumbing not to mention that it might peel the skin off your back while in the pool :lol:. Seriously though, you could probably get away with 1 1/2 HP pump but it depends on a few things.
First, what kind of the jets are you using and what is the recommended flow rate for each jet? How hard do you want the jets? Also, how much of the 2" flex pipe is used? Is it just on the pad or part of the underground plumbing? If most is 2 1/2" plumbing, then you could go up to 2 1/2 HP but I still think that even that may be too much.
I don't know your exact plumbing set up but if I look use the plumbing numbers for my spa, I have 2 1/2" plumbing, and assume 6 jets, then here are a few numbers to consider.
3 HP Whisperflo, 83 feet of head loss, 106 GPM (18 GPM/Jet)
2 HP Whisperflo, 69 feet of head loss, 96 GPM (16 GPM/Jet)
1.5 HP Whisperflo, 65 feet of head loss, 92 GPM (15 GPM/Jet)
You can see that the extra HP doesn't really get you much more flow per jet because of the head loss. You really need 3" pipe for a 3 HP pump and probably even for a 2 1/2 HP pump. Since most spa jets use 15 GPM per jet, it may be possible to go down to a 1.5 HP pump and still have enough power for the jets but it really depends on the type of jets used. In any case, I don't think you really need more than a 2 HP pump.