Pump replacement help needed
- Thread starter bags23
- Start date
- May 3, 2007
- 16,954
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
It isn't that the two motors are close. That is not what I meant. The 3 HP can hand a load that is close to twice that of the 1.5 HP. But that is irrelevant. Your last motor has a THP of 2.5. The 1.5 HP EZ has a THP of 2.4 or about 4% lower load than the original motor. But since the EZ is variable and the load on the motor is proportional to the cube of RPM, you only need to reduce the RPM by 1.3% to get a load reduction of 4%. So the target RPM needs to be 3400 or less.
However, my guess is that your original motor was probably not at full load anyway so it would not surprise me if you could run at full speed with the EZ without any issues. Motors tend to be rated lower than what they can actually support and this is especially true of pump motors.
However, my guess is that your original motor was probably not at full load anyway so it would not surprise me if you could run at full speed with the EZ without any issues. Motors tend to be rated lower than what they can actually support and this is especially true of pump motors.
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Thanks for the clarification. I was planing on running the 1.5 hp at a much lower rpm for a longer period of time. Would this still be ok? Is it better to get the 3 hp and run it at the lower rpm for a longer period of time? Does it even matter? The only time I would be at the higher rpm is when running the polaris.
- May 3, 2007
- 16,954
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
It doesn't matter which motor you get, the efficiency is about the same so the power draw will be about the same. The only difference is max load/amps.
But you may find that you only need to reduce RPM and not increase run time. Run time is not proportional to the inverse of RPM as some would say. Just run the pump long enough to keep it chlorinated and as clean as you like it.
But you may find that you only need to reduce RPM and not increase run time. Run time is not proportional to the inverse of RPM as some would say. Just run the pump long enough to keep it chlorinated and as clean as you like it.
So I should just stick with the 1.5 hp and not worry about it.
Thanks for your help. There is enough variables to make it confusing.
Thanks for your help. There is enough variables to make it confusing.
I just got the 1.5 hp. At 35% there is almost 1 or 2 lbs reading on the filer gauge. Also there is hardly any flow coming out of the jets. Is this normal when operating in these low flow motors?
- May 3, 2007
- 16,954
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Yes, when running at 35%, you get 35% of the flow and the pressure is much lower too. This is to be expected. But you may find that you need higher RPM/GPM to get the skimmers to work properly so some experimentation may be necessary.