Pump Replacement, Possible Sand Filter Media Replacement and Plumbing Changes

[TexasRon]

The original pump for our pool rusted out. I am looking for advice on what to replace it with--should I go withe same pump or something different?

The pool is 13,500 gallon above ground using salt. The salt cell was replaced last year. The sand was washed two years ago. This site was very helpful with getting the pool in better shape than ever, which is why I am coming back to you folks for advice on the pump and two other issues:

--the sand works good, but I always use DE once or twice a week to clean the water a bit more. Would another filter media do a better job?

I am going to have to remove the sand filter to bolt down the new pump anyway, so now would be as good of time as any to change media.

--I would like suggestions on plumbing changes. I would like some valves to isolate the pump and/or filter for service and cleaning.

Our neighbor's new pool is hard-piped but would it be better to use flexible PVC or something and add valves?

--Moving the pump.

Ours is right next to the pool...maybe 18" to the edge of the stand. I am considering moving it back a couple of feet and also raising it up 1'-2'. Any thoughts on that?

 

[YippeeSkippy]

I'm confused by your use of DE in the sand filter "once or twice a week" ? Are you backwashing that often? The DE should be remaining in the filter until you backwash, and we only recommend doing that when the filter pressure rises 20-25% over clean baseline pressure.

If you're going to keep using the sand filter I would recommend sticking with....sand! The alternative filter medias made from glass and other materials haven't really had great recommendations for them and many folks end up going back to sand. And as you know, adding a bit of DE to the sand filter helps it filter smaller particles out.

But you shouldn't be needing to add DE all that often......

Maddie

 

[TexasRon]

I backwash once a week or so but I did notice that the DE seems to catch a lot more "stuff" than the sand. This means that the pump flow slows down and the pressure rises within an hour or two of adding the DE. I may add DE and backwash a couple of times in a day.

I need to do a better job of testing the pool, but I do get some algae growth at times. It dies quickly and I use the DE to help get rid of the debris more quickly.

Are some brands of sand better than others at filtering?

 

[YippeeSkippy]

You're backwashing entirely too often, IMO.

Are you monitoring your filter pressures? Only backwash when the pressure rises 20-25% over clean baseline pressure. And yeah, adding a little DE will raise the pressure too so that is why we advise you to only add as much as it takes to raise the pressure 1 pound. Perhaps you're adding too much??

Did you know that a slightly dirty filter actually works better than a scrupulously clean one? Yup! It does.

If you're getting algae that is a chemistry problem, not a filtering one. I've never had algae in 7 years of pool ownership. Something is wrong with your chemistry if you're getting it (or not properly getting rid of it) that often. Tell me about your testing and how you chlorinate your pool?

Maddie

 

[TexasRon]

You're backwashing entirely too often, IMO.

Are you monitoring your filter pressures? Only backwash when the pressure rises 20-25% over clean baseline pressure. And yeah, adding a little DE will raise the pressure too so that is why we advise you to only add as much as it takes to raise the pressure 1 pound. Perhaps you're adding too much??

Did you know that a slightly dirty filter actually works better than a scrupulously clean one? Yup! It does.

If you're getting algae that is a chemistry problem, not a filtering one. I've never had algae in 7 years of pool ownership. Something is wrong with your chemistry if you're getting it (or not properly getting rid of it) that often. Tell me about your testing and how you chlorinate your pool?

Maddie

My testing routine has not been good; once I open up the pool again, getting better about doing the testing and keeping things "right" will be next. Right now, I am concentrating more on:

--what pump to buy
--the type of media used (sticking with sand based on your advice, thanks!) and whether some sand is better than others based on standards of differing providers
--plumbing the pool so cleaning things is easier

I have a salt system.

While I will listen to advice on testing, there isn't any testing going on since the pool is dead right now. I would call my previous testing routine "poor" but the pool was nice most of the time in spite of that. I used those strips from the pool store and also samples tested in the store. I realize I need to up my game there.

 

[YippeeSkippy]

I would suggest you take a look at your current sand and see if it is the proper grade, and that your filter is filled up to about 3/4 full?
Check this post out for information on sand --> My findings on how not all sand is created equal

Look under "Settings" at the top right of this page and find "Edit Signature" on the left hand side. Knowing what size, type and features your pool has helps us answer your questions better. Please list all your equipment in use.

Maddie

 

[setsailsoon]

TRon,

Looks like others have you well-covered on what appear to be your most urgent filter and algae issues so I'll add in some info on your pump questions:

• The photo of your Hayward pump doesn't look that bad to me. Is it leaking or noisy? If so consider a rebuild. They will replace your o-ring gaskets, seals, bearings for about half price of a new pump.
• If you decide to replace your pump you can buy a direct replace or any similar pump from the major manufacturers. Hayward seems to have a better reputation on this site than some others. But I don't see much difference in the technical specs.
• If you move or replace the pump make sure to have the electrical work performed by a qualified person with particular attention to the safety aspects of the grounding and bonding plus make sure the pump is properly attached to the concrete base.
• Yes you can move the pump as you proposed. Properly installed, pool pumps are self-priming and your configuration will yiield positive NPSH since it will probably have the pool water level well above the suction.
• Yes, you can add a valve between the pool and the pump. Use a full-port, quarter-turn ball valve. Also don't add more valves than you need. Each one is an added pressure drop and more important each one is a potential leak source.
• I prefer hard-piped with union fittings where needed to allow removal of equipment. Flexible pipe offers easier installation since fittings don't need to align as closely. But flex-pipe also has more pressure drop and is more prone to failure. Installing properly within hard pipe tolerance isn't that hard if you take your time.

I hope this is helpful.

Chris

 

[TexasRon]

The pump is entirely rusted out on the bottom. It is unsafe to operate.

The people who installed the pool put it in with an extension cord only. I added a circuit and ran conduit to the area, adding a GFCI plug for the pool equipment. That circuit is dedicated to the pool equipment. Once that was added, the pump ran much more efficiently. It was not bonded, which is something that I will do this time.

I don't think the pump was connected to the concrete base at all--it is one of those systems where the pump is attached to the base for the pump and filter. I am guessing that the weight of the filter sand and water keeps it from moving.

 

[setsailsoon]

The pump is entirely rusted out on the bottom. It is unsafe to operate.

The people who installed the pool put it in with an extension cord only. I added a circuit and ran conduit to the are, adding a GFCI plug for the pool equipment. Once that was added, the pump ran much more efficiently. It was not bonded, which is something that I will do this time.

I don't think the pump was connected to the concrete base at all--it is one of those systems where the pump is attached to the base for the pump and filter. I am guessing that the weight of the filter sand and water keeps it from moving.

TRon,

Looks like a Power Flow Matrix variety. Not surprising on your installation but that's not the right way to do it. It is supposed to have a concrete base or pad under the pump. Here's an excerpt from the manual:

"Fasten pump to base or pad with screws or bolts to
reduce vibration and stress on pipe or hose joints.
Hayward recommends a minimum clearance around the pad of 18” to
allow adequate access for servicing pump..."

Vibration can be a killer for these pumps. Thank goodness you added a GFCI outlet. Your installer ignored a lot of the instructions from Hayward. Here's a link to the installation manual. Just install per their instructions and you'll be fine.

I hope this is helpful.

Chris

 

[TexasRon]

Is 1.5 hp the right size for a 13,500 gallon pool?

Should I look for a two speed pump?

I'll list the other equipment once I take a look at it and get the info.

 

[setsailsoon]

Is 1.5 hp the right size for a 13,500 gallon pool?

Should I look for a two speed pump?

I'll list the other equipment once I take a look at it and get the info.

Seems like a little large to me... I'll check the sizing charts and get back to you.

Two speed can be more efficient but a lot of this personal preference. If you don't have a spa or water features I would personally prefer just a one-speed. In some jurisdictions they require at least a two speed.

Chris

 

[setsailsoon]

TRon,

Here's the additional information I promised plus a little additional:

• It's hard to do an exact sizing without your layout, actual filter model etc. But making the assumption you don't have an unusually long piping route an that your filter is properly sized I did the following check. Most residential pool pumps are sized for either an 8 hr or 10 hr time to circulate the volume of the pool. Even at 8 hr either pump will work with plenty of room to spare. You only need 28 gpm and the 1 hp provides about 60 gpm making very conservative assumptions. In your pool it will probably do better.
• I'm not sure I saw the capacity of your breaker but the 1.5 hp has a max amperage of 16 so you should have a 20 amp circuit for 115 v pump.
• Both the 1 and 1.5 hp use 1-1/2" piping so changing should be relatively easy.
• The advantage of a two-speed is you can adjust your run time so you get the water turned within the time and you maximize the low speed operation which uses less electricity. For smaller pools like yours and mine it really doesn't save that much compared to just running the one-speed pump the required time. But there are also a lot of additional things to consider such as you may want to have the slower speed just to keep the pool surface clean. Or like in my case where I have a solar array on the roof and slow speed won't produce enough head to lift adequate water flow rate through the heater.
• In your case, I would stay with a single speed unless there's some unusual situation I don't know about. If it were me I'd also reduce to 1 hp. An argument could be made to stay with 1.5 so you don't have to re-do piping but it sounds like your going to modify that anyway and the pump costs aren't that much different.

I hope this helps!

Chris

 

[mknauss]

Some clarification --

Pool turnover is a myth -- read Pool School - Determine Pump Run Time

A two speed pump is the minimum. A single speed pump is an energy hog and horribly noisy. Unless you have a spa or use a suction side cleaner, a small two speed should be sufficient.

 

[setsailsoon]

Some clarification --

Pool turnover is a myth -- read Pool School - Determine Pump Run Time

A two speed pump is the minimum. A single speed pump is an energy hog and horribly noisy. Unless you have a spa or use a suction side cleaner, a small two speed should be sufficient.

Agreed on run time. That said, I ran the calcs a while back though and power savings with the referenced article as a guide. For small pumps, if you run the single speed minimum time of 4 hrs and 8 for low speed as recommended the savings were so little on a small pool that it didn't pay out the increased cost with a reasonable cost of money... I'll run the calcs again just out of curiosity. Maybe cost differences are less and I'll have to eat crow (won't be the first time!). Reality on this pool is you could even go down to 3/4 hp.

As to noise, especially for an above ground pool with the pump so close you've got me!

Best regards,

Chris

 

[mknauss]

Also be aware that come 2021, all single speed pumps greater than 0.7hp will no longer be sold in the USA.

 

[setsailsoon]

Also be aware that come 2021, all single speed pumps greater than 0.7hp will no longer be sold in the USA.

Wow! I didn't realize that. Too bad for people like me. I have to buy a pump that I can't ever benefit from to run my solar heater which ironically saves way more energy than even a VS pump!!

Chris

 

[setsailsoon]

Also be aware that come 2021, all single speed pumps greater than 0.7hp will no longer be sold in the USA.

By the way, I did also look up the calcs. It's based on performance tables for my Jandy 2-speed, 1 HP pump. Shows 1 HP at high speed and .16 hp at low speed. Amps are 7.2 at high and 3 at low. So you get less than 20% of the HP but only reduce amperage to 42%. Given this and the fact the impeller is not optimized for 1725 rpm you really have to run a lot less volume to save any money on power. This may be possible and generate some savings but not much. Now a flaw in the calculation could be the amperage. It is max amps not running amps; I couldn't find running amps. I meant to get real running amps myself with my clamp on ammeter to verify the ratio would be the same but I've never done that. I think some of this happens because the motors are induction not permanent magnet and an induction motor is apparently much less efficient. This is about the edge of my electrical knowledge. Also don't want to hijack this thread so I'll leave it at that. You win either way on the noise issue anyway!
Thanks for the clarification.

Best regards,

Chris

 

[TexasRon]

This is a list of the equipment on our 21' above ground pool:

Sand Filter Hayward Model S210T

Hayward Goldline AQ-TROL-RJ AquaTrol Above-Ground Swimming Pool Salt Chlorination System (replaced original in 2017)

Hayward Power Flo Matrix 1.5 hp Pump (original is now broken)

 

[setsailsoon]

TRon,

I've provided my $.02 on most of your questions earlier but I doesn't address the filter. It seems that most of the real experienced experts here will concur a sand filter does the best filtration. But like almost everything pool there are a lot of different opinions. And often specifics about the installation and personal preferences of the owner drive the answer. There have been major improvements in filter element technology and they now offer very large filters. So many (me included) prefer them. Here's my simplistic evaluation:

Advantages

• Simple to operate, no 3-way or MPV needed.
• Long time between filter cleaning
• Pretty cheap
• Less water loss from backflushing

Disadvantages

• Don't quite filter the tiniest particles (usually not needed for a sparkling clean pool)

I'm sure there will be a lot of differing views. You should evaluate all of them through the lens of your specific requirement and preferences.

I hope this is helpful.

Chris

PS I'm jealous of your SWG and I'll be switching soon.

 

[TexasRon]

Thanks for all of your input so far...I am ready to get this show on the road and bring the pool back to life.

Some of the pumps I have looked at seem to look like you use threaded pieces screw into them; others look like the pieces screw onto them (outside threads).

Any issues with which way things are attached?

I am looking at one HP, two speed Hayward right now but I am open to other suggestions. I look at the cost thing like I looked at it on my AC--they told me it would be a long time to recover the extra cost for a two stage system, but the comfort of it is much better for us...so it didn't matter. If the consensus is the two speed pump is better overall, even at an extra cost, I will go in that direction.