Pool Pump Sizing

[Tegguy]

So this might be a rookie set of questions but I'm learning here (never owned a pool before).... Contemplating owner build pool and currently working with someone on the design. I have a few questions about pump sizing after trying to do some research. I'm sorry but I'm going to have so many questions (just trying to do my homework)

1) When calculating the total gallons it's Pool + Spa correct?
2) When calculating the turnover time what is the standard? 1X per day or 2X? 8 Hours? 10 Hours?
3) How to water features play into pump sizing? For example if I have a couple bubblers and sheer decents?
4) I know there are flow vs head curves.... Are there any curves about pump speed vs efficiency/power consumption?
5) We have a solar system for power and would plan to increase the size of it to cover the cost of the pump. Is this amount of electricity needed something that can be estimated?

Additional question...
1) I'm assuming the sheer decents and bubblers only get turned on when people are enjoying them and don't run all the time so I'm assuming they don't really count in the pool turnover
2) Under normal operating (when no one is using it) does water flow into both the spa and the pool and get return from both?
3) I'm assuming the pool and the spa have their own return so when you're in the spa you're only circulating that water. Should both these returns be the same size or should one be smaller?

 

[mas985]

1) Correct
2) Ignore turnovers. Minimum run time is about 2 hours for those manually dosing and other factors do not come into play. SWGs usually require more run time. Skimming, heating and other factors come into play when determining run time. The only way to determine pump run time is with trial and error.
3) You need to determine the flow rate requirements of each feature. These are usually set by the manufacture.
4) You won't find much in the way of published curves but I do have a few tools in my signature that can give you an idea of the energy use and pump comparisions.
5) Yes, see spreadsheets

1a) Ignore turnovers. Some people run features all the time while others just when swimming. It is up to you.
2a) It can be done either way. Again, personal preference. Some controllers allow you to have separate schedules for pool, spa, and spa spillover.
3a) Same size is fine.

One more thing. With a new pool, you should only consider a VS pump. Then pump sizing really doesn't matter.

 

[Tegguy]

1) Correct
2) Ignore turnovers. Minimum run time is about 2 hours for those manually dosing and other factors do not come into play. SWGs usually require more run time. Skimming, heating and other factors come into play when determining run time. The only way to determine pump run time is with trial and error.

So how do you size the pump initially?

We will have a salt chlorinator and also a heater for the spa only for intermittant use.

3) You need to determine the flow rate requirements of each feature. These are usually set by the manufacture.

Just take these and add them up? Does this GPM go on top of the turn over requirement or is this just to ensure the pump will be big enough?

4) You won't find much in the way of published curves but I do have a few tools in my signature that can give you an idea of the energy use and pump comparisions.

Thanks I'll take a look at them

5) Yes, see spreadsheets

1a) Ignore turnovers. Some people run features all the time while others just when swimming. It is up to you.

This is similar to above and the pump size if it's water features + pool turn over or how it plays into the calc.

2a) It can be done either way. Again, personal preference. Some controllers allow you to have separate schedules for pool, spa, and spa spillover.

Plan to have the pantair automation system with independent valve's as much as I can. Is one better than the other (seems like you'd need to suction the spa to get the bottom water to circulate)

3a) Same size is fine.

Is there such a thing as too big of piping? I know the velocity would decrease with pipe size increase. Which might impact the water features?

One more thing. With a new pool, you should only consider a VS pump. Then pump sizing really doesn't matter.

Definatly plan to go VS.

 

[mas985]

Again, stop thinking in terms of turnovers. It just doesn't matter. Despite what you read on the internet there is NO requirement for a certain number of turnovers per day. That is myth. A pool can run just fine with 1/10th of a turnover or 10 turnovers. The only thing that really matters is getting the proper amount of chlorine in the pool and circulating it. With manual dosing, that is only about 30 min per day. For you, SWG chlorine production rate will most likely dictate the amount of run time your pool will need. Some forum members run as little as 30 min per day while others like to run 24/7 with a VS pump (mostly because they want a debris free pool surface). So once you have the FC level you need in the pool and circulated, you can stop pump or leave it running. It is entirely up to you and how debris free you like the pool. There is no typical run time and there is no "required" run time. However, we do have some guidelines to get you started:

Determine Pump Run Time

To figure out how many hours you need to run your pump, you need to know how fast your pump works. You can find this here.

www.troublefreepool.com

These guidelines are very conservative and there is a good chance you can get away with much less run time if you desire.

If you going for a VS, get a full size VS pump (e.g. Intelliflo, TriStar 2.7) and none of this is going to mater. These pumps have more than enough flow rate for almost any water feature and you can dial it down to very low flow rates for just the SWG. Think of a VS pump as a variable "Size" pump. Sizing is no longer required with VS pumps.

However, if you have a very high flow rate requirement for a very large waterfall or infinity edge, then you may need a special purpose pump for just that application. Then we can talk about pump sizing. But for most pools, that is not necessary.

Also, pipe size cannot be too big although it may not help anything either so you are just wasting money if you go too big. The most important thing is to design the water features with large enough pipe sizes because they usually require high flow rate. This is especially true with spas.

Spa design is one of the most frequent PB failures we see on the forum. They just don't seem to know how to design them properly. So if you do plan on getting a spa, do yourself a favor and run the design by the forum for comment.

 

[Tegguy]

Again, stop thinking in terms of turnovers. It just doesn't matter. Despite what you read on the internet there is NO requirement for a certain number of turnovers per day. That is myth. A pool can run just fine with 1/10th of a turnover or 10 turnovers. The only thing that really matters is getting the proper amount of chlorine in the pool and circulating it. With manual dosing, that is only about 30 min per day. For you, SWG chlorine production rate will most likely dictate the amount of run time your pool will need. Some forum members run as little as 30 min per day while others like to run 24/7 with a VS pump (mostly because they want a debris free pool surface). So once you have the FC level you need in the pool and circulated, you can stop pump or leave it running. It is entirely up to you and how debris free you like the pool. There is no typical run time and there is no "required" run time. However, we do have some guidelines to get you started:

Determine Pump Run Time

To figure out how many hours you need to run your pump, you need to know how fast your pump works. You can find this here.

www.troublefreepool.com

These guidelines are very conservative and there is a good chance you can get away with much less run time if you desire.

If you going for a VS, get a full size VS pump (e.g. Intelliflo, TriStar 2.7) and none of this is going to mater. These pumps have more than enough flow rate for almost any water feature and you can dial it down to very low flow rates for just the SWG. Think of a VS pump as a variable "Size" pump. Sizing is no longer required with VS pumps.

However, if you have a very high flow rate requirement for a very large waterfall or infinity edge, then you may need a special purpose pump for just that application. Then we can talk about pump sizing. But for most pools, that is not necessary.

Also, pipe size cannot be too big although it may not help anything either so you are just wasting money if you go too big. The most important thing is to design the water features with large enough pipe sizes because they usually require high flow rate. This is especially true with spas.

Spa design is one of the most frequent PB failures we see on the forum. They just don't seem to know how to design them properly. So if you do plan on getting a spa, do yourself a favor and run the design by the forum for comment.

Basically what I'm taking from this is buy the biggest pump and problem solved. Efficiency and power draw doesn't matter since the speed can be adjusted.

I'm working through spa design currently trying to decide if we want a spill over or an infinity edge (really liking the look of it).

 

[mas985]

Basically what I'm taking from this is buy the biggest pump and problem solved. Efficiency and power draw doesn't matter since the speed can be adjusted.

Yes, exactly.

I'm working through spa design currently trying to decide if we want a spill over or an infinity edge (really liking the look of it).

Keep in mind that large/long infinity edges use a lot of flow rate which requires a lot of energy and usually a very large and separate pump.

 

[Tegguy]

Keep in mind that large/long infinity edges use a lot of flow rate which requires a lot of energy and usually a very large and separate pump.

Really a separate pump for that? Urgh that sucks. Would that second pump be to get the infinity edge to look nice or does it have anything to do with water circulation?

What is screwed up with spa design most of the time?

 

[mas985]

The extra pump is so there is enough flow rate to go over the edge and carrie the debris away with it.

As for spa design, it is important to use large pipe and a Hartford loop for the air pipe. Most PBs use a blower to compensate for a poor design. If designed properly a spa should not require a blower.

 

[JamesW]

How many linear feet will the infinity edge be?

 

[Tegguy]

How many linear feet will the infinity edge be?

Currently around 30' (probably a little more with design updates)

 

[Tegguy]

As for spa design, it is important to use large pipe and a Hartford loop for the air pipe. Most PBs use a blower to compensate for a poor design. If designed properly a spa should not require a blower.

I'm confused all the Hartford loop stuff I'm finding has it coming off a blower but you're saying it isn't needed.

What do you call large? 2"? Is this for the return and supply?

 

[JamesW]

Is the infinity edge around the hot tub or is it on the pool?

 

[mas985]

Hartford loops only work if they are installed at the spa. The idea is to prevent water from filling the air pipe. If water does not fill the air pipe, it is very easy to clear by the spa jet venturis so a blower is not required.

Another option is to put the air vents with small valves (one per jet) at the spa edge so people have control over there own air flow. This way an air pipe is not necessary, except at the spa, so you don't have to worry about the air pipe filling with water.

As for pipe sizing, you first need to decide on the number jets the spa will have and the style of jet, more specifically the jet nozzle size. The larger the jet nozzle, the more flow rate required per jet. The larger the aggregate flow rate, the larger the pipe that is needed.

As for the infinity edge, a 30' edge with a 1/4" overflow, would require about 135 GPM. An Intelliflo XF could provide that amount of flow with the appropriate plumbing design (i.e. 3" pipe). I would have this pump dedicated to the edge and you would want a separate pump(s) for any other water features and the spa so they can be run at the same time. You might end up with 3 pumps: edge, spa and features so each can be run isolated from the others.

 

[Tegguy]

Hartford loops only work if they are installed at the spa. The idea is to prevent water from filling the air pipe. If water does not fill the air pipe, it is very easy to clear by the spa jet venturis so a blower is not required.

Another option is to put the air vents with small valves (one per jet) at the spa edge so people have control over there own air flow. This way an air pipe is not necessary, except at the spa, so you don't have to worry about the air pipe filling with water.

As for pipe sizing, you first need to decide on the number jets the spa will have and the style of jet, more specifically the jet nozzle size. The larger the jet nozzle, the more flow rate required per jet. The larger the aggregate flow rate, the larger the pipe that is needed.

As for the infinity edge, a 30' edge with a 1/4" overflow, would require about 135 GPM. An Intelliflo XF could provide that amount of flow with the appropriate plumbing design (i.e. 3" pipe). I would have this pump dedicated to the edge and you would want a separate pump(s) for any other water features and the spa so they can be run at the same time. You might end up with 3 pumps: edge, spa and features so each can be run isolated from the others.

I think I have a lot to learn here (sorry).... So I'm trying to find plumbing information with no blower but every hartford loop has a blower on it. Do the spa jets blow air or water?

Do you have any recommendations for number of jets, style of jet and size? I have attached an image of our current spa shape for reference. 3 Pumps seems expensive for startup operation and running operation (some contractors were offering 2 to be able able to run the spa and water features). I'm assuming there are a couple reasons for this (maybe) 1) When using the spa you want the full power of the pump to be directed at the jets and not shared with the water feature and 2) this allows you to pump heated water back to the spa only so you're not heating the pool. Am I close?

Is the infinity edge around the hot tub or is it on the pool?

Was only intended to be around the spa. I have attached images of our 2 ones we're looking at (pool designs by different people)

 

[JamesW]

Ok, the infinity edge looks nice, but from an operational perspective, it's not a great choice, in my opinion.

 

[JamesW]

For a pool infinity edge, I would do a separate pump.

For a spa, I would treat it as a normal spillover feature and not use a separate pump.

Note that the infinity edge has to be as close to perfectly level and straight as possible.

 

[Tegguy]

For a pool infinity edge, I would do a separate pump.

For a spa, I would treat it as a normal spillover feature and not use a separate pump.

Note that the infinity edge has to be as close to perfectly level and straight as possible.

I think as cool as it looks I'm leaning towards the L shaped spill over but I'm not sure. I was also thinking the spa being raised 12" or 18" could function as seating if we didn't do the infinity edge.

 

[mas985]

I think I have a lot to learn here (sorry).... So I'm trying to find plumbing information with no blower but every hartford loop has a blower on it. Do the spa jets blow air or water?

Both. There is an air line and a water connected to the jet. But the spa jets don't necessarily require a blower. That is optional if designed properly.

Do you have any recommendations for number of jets, style of jet and size? I have attached an image of our current spa shape for reference.

Not really. It is most about what you want out of the spa. There are dozens of spa jets available. Just keep in mind the flow rate requirements and the number of jets.

3 Pumps seems expensive for startup operation and running operation (some contractors were offering 2 to be able able to run the spa and water features). I'm assuming there are a couple reasons for this (maybe) 1) When using the spa you want the full power of the pump to be directed at the jets and not shared with the water feature and 2) this allows you to pump heated water back to the spa only so you're not heating the pool. Am I close?

The 3 pumps was for a pool infinity but you still may want three pumps. It just depends on how many you want to operate at the same time.

Plumbing Loops

#1 Infinity Edge
#2 Spa Jets
#3 Spa Heating and Filtering
#4 Pool Water Features - It may be good to have separate returns to separate features to have full control over flow to the individual features
#5 Pool Returns/Skimmer

#1 and #2 could be run on a single pump with valving that switch between the two functions. Both should avoid going through the filter.

#3, #4 & #5 could be put on a single pump but then you would have to shut off the water features while heating the spa.

You could skip loop #3 and heat through the spa jets which is done fairly often but the the heater may not be available for the pool without complex valving.

If you want filtering for #3, #4 & #5 all at the same time, you really need a third pump and perhaps a second filter.

So you have to think carefully about how the pool will be used and what you want running at the same time.

The L shape design will be far easier to implement.

 

[JamesW]

Note that the complete infinity edge is difficult to get in and out of.

 

[Tegguy]

Both. There is an air line and a water connected to the jet.

Not really. It is most about what you want out of the spa. There are dozens of spa jets available. Just keep in mind the flow rate requirements and the number of jets.


The 3 pumps was for a pool infinity but you still may want three pumps. It just depends on how many you want to operate at the same time.

Plumbing Loops

#1 Infinity Edge
#2 Spa Jets
#3 Spa Heating and Filtering
#4 Pool Water Features - It may be good to have separate returns to separate features to have full control over flow to the individual features
#5 Pool Returns/Skimmer

#1 and #2 could be run on a single pump with valving that switch between the two functions. Both should avoid going through the filter.

#3, #4 & #5 could be put on a single pump but then you would have to shut off the water features while heating the spa.

You could skip loop #3 and heat through the spa jets which is done fairly often but the the heater may not be available for the pool without complex valving.

If you want filtering for #3, #4 & #5 all at the same time, you really need a third pump and perhaps a second filter.

So you have to think carefully about how the pool will be used and what you want running at the same time.

The L shape design will be far easier to implement.

Holy cow so much good and helpful information on this site! First of all let me say thank you to everyone who has helped me thus far. I've honestly never built or owned a pool or spa so it's hard to say what I want out of it. I was thinking it'd be more like a hottub thing like I had growing up (seperate hottub above ground) and would be like a therapy setup. So is the air line ran all the way back to the equipment pad and just left open (unless a blower is added)? I think maybe that's where my confusion is. Also is there a hartford loop at each jet or 1 for the entire spa?

When you say "return loop" does this mean basically having a dedicated return run all the way back to the pump inlet with a valve separating each return before entering the pump (sorry trying to understand terminology)? When doing automation I assume you have to have control over both the return and the supply side. I assume it's probably a good idea for each water feature to have it's only supply valve as well especially if doing different sizes and types of water features (for example 2 different lengths of sheer decents)? I'll have to ask the wife if she would like to have the water features run while in the spa or not

I don't plan to heat the pool but I guess it would be nice to have just incase. So in this case the spa would have it's only return and supply lines and they jets would operate independently? I might have to sit down and draw this out so I can understand it.

When you said "if you want filtering for #3, #4, & #5 all at the same time" you basically mean if we want to have the spa heating, the water features on and circulating the pool we would probably need 3 pumps and 2 filters. I guess I'm not sure how to come up with the answer to "how the pool will be used". All our neighbors have a single pump but I know there are limitations to that (what the exact limitations are I'm not 100% clear on).