So we're getting closer to building our pool, we haven't decided exactly which kind of filter etc but I thought I'd solicit recommendations. We're planning an 18x36 rectangle with a 6 or 7 ft deep end, I'm guessing around 24k gallons. Any ideas on recommended filter sizes for that in sand, DE and cartridge? I'm thinking about a 1.5hp 2 speed pump with 2 inch plumbing if that has any effect on the recommendation. Also if any of that sounds wrong, please let me know before I start clarifying bids.
Equipment sizing recommendations
- Thread starter Blueskies21
- Start date
I would suggest a 1 HP 2 -speed for the size of your pool. It'll move plenty of water and save a lot of money over a 1.5 HP.
If you decide on a 1 HP, a filter capable of moving around 100 GPM or so is a good match.
If you decide on a 1 HP, a filter capable of moving around 100 GPM or so is a good match.
Thanks Duraleigh. So in general the bigger the filter the better as long as the GPM is around 100? For example one builder was saying a 48 sq ft DE. How much of a size change if I were to use a 1.5 hp or how can I figure that GPM?
You can get your pump GPM from the manufacturer's pump curve assuming a typical head loss of about 50. Generally, you will find that a 1 HP pump will produce about 70-80 GPM in your situation.
So, a really good rule of thumb is to get a filter who's gpm rating exceeds your pump's production by roughly 25%...hence, somewhere around 100GPM filter.
The GPM rating is most always printed plainly on the filter so that shouldn't be an issue.
A 1.5 HP pump is pretty much overkill for your system and would simply waste electricity and offer you no benefit.
So, a really good rule of thumb is to get a filter who's gpm rating exceeds your pump's production by roughly 25%...hence, somewhere around 100GPM filter.
The GPM rating is most always printed plainly on the filter so that shouldn't be an issue.
A 1.5 HP pump is pretty much overkill for your system and would simply waste electricity and offer you no benefit.
- May 3, 2007
- 16,815
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Below is a chart of several two speed pump flow rates. The blue bars represent typical 1.5" plumbing while the red bars indicate typical 2" plumbing. You will notice is that not all 1 HP pumps are the same. There are some that have very low flow rates and some that have very high flow rates. The point being that it is nearly impossible to size a pump based only on it's label HP. Also, the lower the flow rate, the more energy you will save, so if you don't need the flow rate, you are better off going with a smaller, lower flow rate pump. I agree that a 1.5 HP is too big but a 1 HP pump might be unnecessary too. For example, 1 HP Whisperflo is a large pump for it's HP label rating and is actually larger than some 2 HP pumps (Maxflo) so don't just go by the label HP when sizing a pump. Does your PB have a manufacture preference?
Seems like most of the pool builders around here like Hayward but I have seen some Pentair as well. Doesn't seem like Jandy is too prevalent, I have only seen one builder who used them and they were about 15k high on the total price of the pool so they must think they're pretty special.
- May 3, 2007
- 16,815
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Forgot ask if you were planning on any other water features and/or having a controller?
So we're considering deck jets or a waterfall but neither of those has been solidly decided as a yes. Right now, we're not planning automation due to price but might reconsider if we could squeeze the money from something else.
- May 3, 2007
- 16,815
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
I would decide on the jets and the waterfall first because that can influence the type and size of pump.
Without a controller, how do you plan on turning the pump on and off?
There are a few reasonably priced VS pumps that come with timers such as the Hayward SP2300VS. But the flow rate on that tops out at about 70 GPM which may or may not be able to support the jets, waterfall and returns all at the same time.
Without a controller, how do you plan on turning the pump on and off?
There are a few reasonably priced VS pumps that come with timers such as the Hayward SP2300VS. But the flow rate on that tops out at about 70 GPM which may or may not be able to support the jets, waterfall and returns all at the same time.
Honestly I don't know, I guess I was thinking an intermatic timer or something? Though honestly it looks like the Prologic controllers aren't much more than a goldline salt system by itself. I guess the question then is how many relays/ valves do I need? So if I plumbed 4 returns separately and then had a 3 way on the suction line to split the skimmer and the main drains, I guess that's five valves even without deck jets or waterfall so that puts me in an 8 valve controller. For relays, two lights, a pump and possibly a heater, so 4 relays unless a 2 speed pump requires 2 relays. Do you know how that works with controllers?
- May 3, 2007
- 16,815
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Yes, a two speed pump required two relays.
But you really need to decide on these factors before even thinking about sizing the pump and then filter. Those two things should be sized last.
But you really need to decide on these factors before even thinking about sizing the pump and then filter. Those two things should be sized last.
Thanks for the help so far Mas. How much difference in pump sizing would either deck jets or a waterfall make? From reading Jandy's deck jet manual it seems like each deck jet requires 5 gpm. So worst case scenario is 20 GPM increase with 4 deckjets, not sure what size of waterfall we'd be thinking or the GPM requirements of waterfalls in general. Sorry I don't have better answers.
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