I can't seem to find this info on the Hayward site. Could you give me an exact link?
Very noisy pump... Do I need a new one? Or just replace the motor? Or bearings?
- Thread starter Westovers
- Start date
I can't seem to find this info on the Hayward site. Could you give me an exact link?
TriStar | Pumps | In Ground Pool Pumps - Hayward Pool Products
This page has all of the information you need. It has a link to parts, specs, manual etc.
This page has all of the information you need. It has a link to parts, specs, manual etc.
Looking at the Hayward website, description of SPX3210C says: Impeller-1Hp for new construction & the aftermarket, TriStar® is the most hydraulically efficient pool pump that provides superior flow and energy efficiency. Most hydraulically efficient wet-end - can often step down in pump size(HP) -- same performance at a lower installation cost and cost of daily operation. Maintain the same size and, with greater flow, run the pump less per day, saving energy and money.
How can I convince my mechanic that this is a bad match if it has this description and states 1HP?
1hp is the "rated" hp, not the total hp.
Look at the specs for the pump. They show the total hp of each pump.
Your pump came with a 1.85 total hp motor and a SPX3210C impeller.
You have a SP3210EE pump. Click on the "Specs" button to open that and it shows the rated hp at 1, the service factor at 1.85 and the total hp at 1.85.
Your new motor matches the rated hp, but it does not match the service factor. Both have to match or the total has to match.
If it would be ok with a 1 hp total motor, then why did it come with a 1.85 hp motor?
Check the manual, it shows that the motor for the pump is a SPX3210Z1BER, which is a 1.85 total hp motor.
Look at the label on your original motor, it shows 1.85 hp.
You can also check with Hayward to see what they say. Email them vs calling.
I do understand the confusion about how pumps are rated. In my opinion, they need to eliminate the rated hp, service factor and total hp and just use total hp. That way a 1 hp pump would use a 1 hp motor and a 1 hp impeller.
The full rated tristar pumps are the same pumps as the max rated ones. So, it's pointless to have both.
I'm not sure how the whole service factor thing started.
Probably, back when motors were first developed, the power and loading were more variable and motors tended to overload so engineers added a safety factor.
In any case, I think that it's counterproductive today and should be changed to total hp. The rated hp would be the total hp and the service factor would always be 1.0.
Look at the specs for the pump. They show the total hp of each pump.
Your pump came with a 1.85 total hp motor and a SPX3210C impeller.
You have a SP3210EE pump. Click on the "Specs" button to open that and it shows the rated hp at 1, the service factor at 1.85 and the total hp at 1.85.
Your new motor matches the rated hp, but it does not match the service factor. Both have to match or the total has to match.
If it would be ok with a 1 hp total motor, then why did it come with a 1.85 hp motor?
Check the manual, it shows that the motor for the pump is a SPX3210Z1BER, which is a 1.85 total hp motor.
Look at the label on your original motor, it shows 1.85 hp.
You can also check with Hayward to see what they say. Email them vs calling.
I do understand the confusion about how pumps are rated. In my opinion, they need to eliminate the rated hp, service factor and total hp and just use total hp. That way a 1 hp pump would use a 1 hp motor and a 1 hp impeller.
The full rated tristar pumps are the same pumps as the max rated ones. So, it's pointless to have both.
I'm not sure how the whole service factor thing started.
Probably, back when motors were first developed, the power and loading were more variable and motors tended to overload so engineers added a safety factor.
In any case, I think that it's counterproductive today and should be changed to total hp. The rated hp would be the total hp and the service factor would always be 1.0.
Thank you James--that's very helpful. I will do my best to explain, and have printed the specs sheet from the website for the Tristar pumps showing the impeller/pump matches.
I have scoured all of the pool supply stores in my area (Austin, TX) and unfortunately I can not obtain the correct impeller today, but we are about to have 3 days straight of sub-zero temps for the holiday weekend, forcing the pump to operate 24/7. I'm guessing/hoping that because this pump is just pushing water through a pipe to a waterfall and will not be under a lot of pressure (like it would be pushing water through a filter and heater) it will therefore not do damage in the next few days, especially because the temps will be cold anyway? Is that naive? I'm also thinking that it will be better to open my waterfall valve all the way open for now so that the motor will be under less stress--not having to push as hard? This makes the waterfall look unrealistic, of course, with water gushing out, but would better serve the under powered motor, right? Then I can get the correct impeller installed next week... What do you think? What would you do?
It's counterintuitive but, running with less pressure actually increases the power use by the pump because you're moving more water in gpm.
Higher pressure would increase power use if the gpm stayed the same. However, the gpm decreases with more resistance, which uses less power. So, the net effect is slightly increased power usage with lower pressure or higher power with less pressure (resistance).
I would probably just winterize the fountain. Pull the drain plugs and blow out the fountain line.
Alternatively, if you don't want to do that, you probably just need to let it run. Hopefully, it's not going to cause any permanent harm to the motor. Keep it restricted like you want.
Higher pressure would increase power use if the gpm stayed the same. However, the gpm decreases with more resistance, which uses less power. So, the net effect is slightly increased power usage with lower pressure or higher power with less pressure (resistance).
I would probably just winterize the fountain. Pull the drain plugs and blow out the fountain line.
Alternatively, if you don't want to do that, you probably just need to let it run. Hopefully, it's not going to cause any permanent harm to the motor. Keep it restricted like you want.
Great, thank you. The pump is downhill from the waterfall and pool level, so I'm not sure how to winterize, as there are no valves to close near the pump. So I will partly close the valve near the waterfall, limiting the gpm but increasing the pressure for the pump... That does seem counter intuitive!
Thank you again for all of your help.
Here are some examples of how it works.
If you have 4 pools, A, B, C and D. A is at ground level, B is 30 foot higher than A. C is 50 foot higher than A. And, D is 70 ft higher than A. Using your pump, it would pump at 121 gpm going from A to B, 97 gpm going from A to C and 60 gpm going from A to D. (Ignores dynamic head loss). This shows how gpm reduces as head loss increases.
Using a SP3205EE pump (1.0 total hp) and assuming 30 ft head loss, you would have to switch to a SP3210EE pump (1.85total hp) to maintain the same flow rate if the head loss changed to 62 ft. This shows that more power is required if the head loss (restriction) is increased and the flow rate is maintained.
To determine what percentage of flow you can expect by changing from your current impeller to a SPx3205C impeller, there are a few ways to do it.
One way is to use the pump affinity law, which states that the power required is proportional to the change in flow rate cubed (real world is more like x^2.585).
(V2/V1)^2.585 = 1.0/1.85.
V2/V1 = 0.79 or 79%.
Another is to plot a system curve on the pump curve chart to see where the system curve intersects the pump curve of each pump. Assuming that the system curve intersects the SP3205EE pump curve at 30 ft of head and 75 gpm, we can estimate that the system curve will intersect with the SP3210EE pump curve at about 49 ft of head and 97 gpm. 75/97 = 0.77 or 77 %
So, we can conclude that switching to a SPX3205C impeller should give us about 77% to 79% of the flow of the SPX3010C impeller.
The system curve varies based on the pump affinity law, which also states that the head loss is proportional to the change in flow rate squared. (V2/V1)^2 = H2/H1
If you have 4 pools, A, B, C and D. A is at ground level, B is 30 foot higher than A. C is 50 foot higher than A. And, D is 70 ft higher than A. Using your pump, it would pump at 121 gpm going from A to B, 97 gpm going from A to C and 60 gpm going from A to D. (Ignores dynamic head loss). This shows how gpm reduces as head loss increases.
Using a SP3205EE pump (1.0 total hp) and assuming 30 ft head loss, you would have to switch to a SP3210EE pump (1.85total hp) to maintain the same flow rate if the head loss changed to 62 ft. This shows that more power is required if the head loss (restriction) is increased and the flow rate is maintained.
To determine what percentage of flow you can expect by changing from your current impeller to a SPx3205C impeller, there are a few ways to do it.
One way is to use the pump affinity law, which states that the power required is proportional to the change in flow rate cubed (real world is more like x^2.585).
(V2/V1)^2.585 = 1.0/1.85.
V2/V1 = 0.79 or 79%.
Another is to plot a system curve on the pump curve chart to see where the system curve intersects the pump curve of each pump. Assuming that the system curve intersects the SP3205EE pump curve at 30 ft of head and 75 gpm, we can estimate that the system curve will intersect with the SP3210EE pump curve at about 49 ft of head and 97 gpm. 75/97 = 0.77 or 77 %
So, we can conclude that switching to a SPX3205C impeller should give us about 77% to 79% of the flow of the SPX3010C impeller.
The system curve varies based on the pump affinity law, which also states that the head loss is proportional to the change in flow rate squared. (V2/V1)^2 = H2/H1
Whew! You sure lost me there. But 77-79% of present flow should be plenty.
HOWEVER, based on your previous post, I'm wondering if we should keep the present impeller with the valve restriction in order to reduce the power used by the motor (and thereby even save electricity)?? Or did I misunderstand...
The restriction makes a relatively minor difference. The impeller is too big and definitely should be replaced. The SPX3205C would be a good choice.
Restricting the flow does increase the power usage, but it also reduces the flow, which reduces the power usage. So, the net effect is a slightly reduced power use.
Switching the impeller to a smaller impeller reduces the flow and the pressure so the power savings are much higher.
Right now, you're probably exceeding the amp rating that's on the motor label.
Restricting the flow does increase the power usage, but it also reduces the flow, which reduces the power usage. So, the net effect is a slightly reduced power use.
Switching the impeller to a smaller impeller reduces the flow and the pressure so the power savings are much higher.
Right now, you're probably exceeding the amp rating that's on the motor label.