It is interesting to note that the wet end determines how much power is used. So if you have an existing 1 Hp wet end, and retro fit with a new 1.5 Hp motor, the motor will only see 1 Hp of load, and your pressure and flow will be the same as with the 1 Hp motor. I changed out my single speed motor for a 2 speed motor years ago and never looked back.
Why even buy a new pump?
- Thread starter FLAK111
- Start date
I want to clarify this point since others have not. The motor will only put out as much power as is needed to maintain the speed. If the IMPELLER only requires 0.69 hp (my made up number) to maintain the speed, then the motor will only put out 0.69 hp. On the flip side, if the IMPELLER requires 1.82 hp, then the motor will try to put out 1.82 hp. The 1.5 hp motor will not put out 1.5 hp just because it can. It only puts out what the IMPELLER needs, if it can. You would not need to change out your wet end just because the hp rating is larger. An impeller rated at 1hp is not really telling the whole story anyway. Impellers only require and consume the power that it takes to move the water. That 1hp rated impeller is normally operating much lower than 1hp. The energy consumption of the motor is based on how it is operating, not on the nameplate rated powers.
My 2hp 2-speed motor only consumes 225 watts on low speed and 1200 watts on high speed. No where near the 2hp (1491 watts) nameplate rating.
I cannot thank you all enough. Total strangers helping out those who ask. Truly appreciate all of your education insight on this subject. Many different points were touched on and has given me and many others a more well rounded understanding. I'll think I'll be getting the VGreen V-speed pump. I don't see a need to change out the wet end if its working just find and i'm just looking for energy savings.
Question, considering this motor has never been taken apart in the more likely 10+ yrs its been going, I know I should change out the gasket and use a motor replacement kit, but is there anything else I should maybe upgrade/replace while im in there?
Question, considering this motor has never been taken apart in the more likely 10+ yrs its been going, I know I should change out the gasket and use a motor replacement kit, but is there anything else I should maybe upgrade/replace while im in there?
I don't recall whether a new shaft seal was included with the pimp at Inyo or if I just ordered it seperately but you do want to change that out. And of course the gasket, which you mentioned. I didn't need to change my impeller because it was fairly new and had previously been replaced due to a hairline crack. If you've had no leaks, yours is likely fine.
Glad we could help out!
Glad we could help out!
Here's a couple of other things to consider.
1. I'd suggest you try to at very least loosen the flange/motor bolts on your pump before you buy the new motor. Just in case you have a problem you won't have a motor that you have to ship back and buy a new pump anyway. Ideally you should disassemble the pump to make sure that you can get the impeller off as well, but you may not want to do that until you have the new motor. If you just want to test the flange bolts, just loosen them one at a time and tighten them back. That way you don't create other problems.
2. If you put a 1 hp impeller (1.25 SF) on a 1.65 hp motor, you still only have a 1 hp pump. It's not going to pump any more or produce any higher pressure than it did before.
There's no danger in putting a smaller impeller on a larger motor. There is a danger in putting a smaller motor on a larger impeller.
1. I'd suggest you try to at very least loosen the flange/motor bolts on your pump before you buy the new motor. Just in case you have a problem you won't have a motor that you have to ship back and buy a new pump anyway. Ideally you should disassemble the pump to make sure that you can get the impeller off as well, but you may not want to do that until you have the new motor. If you just want to test the flange bolts, just loosen them one at a time and tighten them back. That way you don't create other problems.
2. If you put a 1 hp impeller (1.25 SF) on a 1.65 hp motor, you still only have a 1 hp pump. It's not going to pump any more or produce any higher pressure than it did before.
There's no danger in putting a smaller impeller on a larger motor. There is a danger in putting a smaller motor on a larger impeller.
CJadamec
TFP Expert
I agree with Bama, take the pump you have now apart first to find any hidden surprises or frozen bolts you don't know about before ordering the motor. If the pump comes apart easy and every thing is in good shape get the motor. If you find more needs replacing than the wet end is worth in parts consider buying a whole new pump.
I don't fully understand this. Wouldn't head pressure be the primary variable that affects how "hard" a motor works to turn the impeller at the rated speed? All of the pump charts I look at show that as head decreases, GPM increases. Wouldn't that indicate that the motor is usually operating in relatively narrow energy usage range, and changes in head pressure/friction just result in different GPM rates?
Not saying you're wrong at all - just trying to get a better understanding.
The impeller determines how much power the motor uses.
The head loss and gpm are inversely proportional. The net effect is that head loss change has very little effect on power usage. Increase in head loss slightly decreases power usage.
Also, the head loss changes based on flow rate. At double the flow rate, the head loss is four times as much.
So, you have a system curve and a pump curve. When you plot them on the same graph, the operating point is at the intersection of the curves.
The head loss and gpm are inversely proportional. The net effect is that head loss change has very little effect on power usage. Increase in head loss slightly decreases power usage.
Also, the head loss changes based on flow rate. At double the flow rate, the head loss is four times as much.
So, you have a system curve and a pump curve. When you plot them on the same graph, the operating point is at the intersection of the curves.
So a motor/impeller combo is going to use the essentially the same amount of energy all the time?
An impeller will use about the same power regardless of the motor.
If the motor is too small, it will just burn up trying to supply the power.
If the motor is too small, it will just burn up trying to supply the power.
cfherrman
TFP Guide
As head increases, the pump will use slightly less engery, as shown on the head chart.
Slightly, as in 10 watts or less
Slightly, as in 10 watts or less
My system is a little older than new model, but I found my 1 HP pool pump flow chart for my Pentair : Pentair Challenger Standard Efficiency Pool Pump | 346204
View attachment 72504
current pic of system:
View attachment 72505
Expressing my understanding, please chime in if I am not mostly correct:
What I'm gathering from some of these comments and my research, is that even getting a higher rated 1.65 motor on my current 1HP high flow system, it wont change the maximum flow through my 1.5 inch piping becasue my pump is rated for a 1HP pump. But, getting the new vGreen VS 1.65 pump with lower Service Factor making it more like my current 1HP up rated SF 1.25 with basically make the motors act near the same in the overall scheme of things. Having the 1.5 inch piping, it can only handle so much (same with the 1HP pump/impellar), so in the end I should still see electric savings with the new VS 1.65 running at low flow rate over the 24hr period even though I'll probably never get a true benifit from the higher HP capability.
One question I do have is: I have a [h=1]Poolvergnuegen PoolCleaner 2-Wheel Suction Side Cleaner | White & Blue | 896584000-013[/h]https://www.poolsupplyunlimited.com/poolvergnuegen-896584000-013-suction-side-cleaner/81071p1
I noticed with my current 1HP system, I DO NOT get enough suction when I have my return lines in the open position. I have to adjust my valves on my skimmers, so that, I turn off my Main drain, and close 80% of my 2nd skimmer, so that all suction power is for the poolcleaner as it is hooked up to my skimmer 1. Only by doing this do I have enough suction for the pool cleaner to work properly/fast enough per its instruction manual. (ie: 8-11 RPMs for its wheels which indicate proper suction power is attained).
By switching to the new Vgreen 1.65, will I be able to see any difference when using my pool cleaner? or will it basically stay the same since my current 1.5 inch PVC pipe and 1HP pump/impellar are just that, the same. will I be able to not have to turn my valves for my pool cleaner to work since there is a slightly higher HP pump on it when installed?
View attachment 72504
current pic of system:
View attachment 72505
Expressing my understanding, please chime in if I am not mostly correct:
What I'm gathering from some of these comments and my research, is that even getting a higher rated 1.65 motor on my current 1HP high flow system, it wont change the maximum flow through my 1.5 inch piping becasue my pump is rated for a 1HP pump. But, getting the new vGreen VS 1.65 pump with lower Service Factor making it more like my current 1HP up rated SF 1.25 with basically make the motors act near the same in the overall scheme of things. Having the 1.5 inch piping, it can only handle so much (same with the 1HP pump/impellar), so in the end I should still see electric savings with the new VS 1.65 running at low flow rate over the 24hr period even though I'll probably never get a true benifit from the higher HP capability.
One question I do have is: I have a [h=1]Poolvergnuegen PoolCleaner 2-Wheel Suction Side Cleaner | White & Blue | 896584000-013[/h]https://www.poolsupplyunlimited.com/poolvergnuegen-896584000-013-suction-side-cleaner/81071p1
I noticed with my current 1HP system, I DO NOT get enough suction when I have my return lines in the open position. I have to adjust my valves on my skimmers, so that, I turn off my Main drain, and close 80% of my 2nd skimmer, so that all suction power is for the poolcleaner as it is hooked up to my skimmer 1. Only by doing this do I have enough suction for the pool cleaner to work properly/fast enough per its instruction manual. (ie: 8-11 RPMs for its wheels which indicate proper suction power is attained).
By switching to the new Vgreen 1.65, will I be able to see any difference when using my pool cleaner? or will it basically stay the same since my current 1.5 inch PVC pipe and 1HP pump/impellar are just that, the same. will I be able to not have to turn my valves for my pool cleaner to work since there is a slightly higher HP pump on it when installed?
cfherrman
TFP Guide
A suction side cleaner will always need the other suctions off, I don't think 1.65 hp would do that, maybe 3 or 4 hp. That is the nature of the beast so don't fret about it.
The load(impeller) decides on how many watts (hp) are used and won't make a difference on the motor hp, unless the motor hp is way high, like 3-4 hp or more, then it's a efficiency kind of thing. For our uses, there is no difference on a higher hp motor with the same impeller.
If on high speed the 1.65 hp vsp is not noisy or over pressuring your filter, it's a win as you can use it on high, if not it's still a win as you can set it to the same pressure as before and you still have the lower speeds.
The load(impeller) decides on how many watts (hp) are used and won't make a difference on the motor hp, unless the motor hp is way high, like 3-4 hp or more, then it's a efficiency kind of thing. For our uses, there is no difference on a higher hp motor with the same impeller.
If on high speed the 1.65 hp vsp is not noisy or over pressuring your filter, it's a win as you can use it on high, if not it's still a win as you can set it to the same pressure as before and you still have the lower speeds.
CJadamec
TFP Expert
In as few words as possible...
If you keep the same wet end, impeller and housing, the amount of water it moves at full speed will not change.
If you put the vgreen VS motor on you be able to run at low speeds and save electricity. Reducing speed by as little as going from 3450rpm (your current single speed motor rpm) to 3000rpm you will use roughly 50% less electricity. By dropping to 1200 rpm you will only use 1/10th (or less) the energy your current pump uses.
At full speed, 3450 rpm, your current motor and the new VS motor will use the same amount of energy when connected to the same wet end.
If you upgrade to say a new superflo pump your flow dynamics will change because the flow curve for the new pump is different. Oddly enough when run at 1200rpm you will still use roughly the same energy as your old wet end with a new VS motor.
If you keep the same wet end, impeller and housing, the amount of water it moves at full speed will not change.
If you put the vgreen VS motor on you be able to run at low speeds and save electricity. Reducing speed by as little as going from 3450rpm (your current single speed motor rpm) to 3000rpm you will use roughly 50% less electricity. By dropping to 1200 rpm you will only use 1/10th (or less) the energy your current pump uses.
At full speed, 3450 rpm, your current motor and the new VS motor will use the same amount of energy when connected to the same wet end.
If you upgrade to say a new superflo pump your flow dynamics will change because the flow curve for the new pump is different. Oddly enough when run at 1200rpm you will still use roughly the same energy as your old wet end with a new VS motor.
- Jan 4, 2016
- 5,392
- Pool Size
- 44000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
That's a great explanation from CJadamec! Thanks for that 
My cleaner is a Pentair copy of the Poolverneugen. It runs fine at 6 RPM (wheels), though I don't need it to vacuum walls. Takes a bit longer of course. You could try closing the main drain to just a trickle so you get chlorinated water going through, and also reducing the other skimmer some or all. Might work.
My cleaner is a Pentair copy of the Poolverneugen. It runs fine at 6 RPM (wheels), though I don't need it to vacuum walls. Takes a bit longer of course. You could try closing the main drain to just a trickle so you get chlorinated water going through, and also reducing the other skimmer some or all. Might work.