Old, old Laars LLD 325 part number question


I'm up in Dallas trying to heat my brother's pool up so I can dive it to check for water leaks. He has a 25 year old Laars Lite 325 LLD heater that has a failed pressure switch. It is shorting to ground internal to the switch and leaking through the switch housing. When bypassed the heater works fine. The manual lists 3 replacement switches and I can't figure out which one it was since the old one is so old I can't read any of the writing. The 3 listed are:
1 psi
2 psi
1-10 psi

Does anybody know which one we need? I'm guessing it's the 2 psi R0013200 and not sure it's really that critical. The switch that's in there doesn't seem to be a 1-10 psi variable switch from appearance.

Any help would be much appreciated.


Almost done with remodel and Spa has zero water flow

So our old spa had 4 returns and a very thin wall between the pool and spa. We had that wall removed and two more returns add then wall rebuilt. The plumbing at the pump for the spa was never touched and worked all the way up to the day the pool was drained. However now when I switch it into spa mode the pump stops running...not shuts off but like its hydro locked.

I have confirmed all the valves are correct. In fact I have also confirmed the drains in the spa are not the issue as for I can empty the spa into the pool. I have tried to take water from the pool at put into spa but that no longer works either. So it has been nailed down that for some reason no water will flow out of spa returns. I had snapped a cpl pictures before they shot the wall probably wont help much but trying to figure out what is going on here. PB has not responded in several days now to my concern.

I have removed wall returns and internal jets. Looked inside of each return with a snake camera and do not see any issues. So my thought is they did something wrong in this plumbing. Which is now under gunite, plaster, flagstone and cement decking.


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Oceanfront, raised pool design?

I'm just starting the planning process. We are on the oceanfront, but have good dunes between us and the ocean. Still, I wonder if there is a way to raise the pool slightly so that if the ocean breaches the dunes during a storm, the pool won't be flooded. But if it is raised, would the sides/support be washed out in a storm? I have seen pools that are level with the second level of homes, but I don't want a 10-15 foot ugly wall! Has anyone raised a pool just a few feet? Any pictures to share? I presume you would have steps up to the pool deck? I hope my questions even make sense to y'all! Thank you so much!

Advice: Why not have the Pool Heater plumbed to water feature / waterfall piping pathways?

Typically, a pool heater install is to have it plumbed on the piping pathway that includes the Pool Filter.

Will it make sense to have the pool heater plumbed separately instead, say to the water feature/waterfall piping pathway? Because our waterfall feature is turned on only a few times in the year, the use case is likely the same as the pool heater. Granted, this will mean both the pool heater and the waterfall feature may both need to be simultaneously turn on for normal operation. Or, have some heater bypass valves installed.

Our Pool has 3 pumps:
One Polaris booster pump for the pool sweeper ;
One Pentair WhisperFlow 1.5HP being the primary which is connected to the Filter ;
One other identical Pentair WhisperFlow 1.5HP which is an under utilized pump because it connects to the waterfall feature of the pool which also have its own piping pathways. There are 3 waterfall outlets (0.5" x 2 feet wide rectangular) and 2 intakes/return. We don't turn on this waterfall feature much at all...

Would like to know if anyone here on TFP have considered/discussed connecting a pool heater on the separate piping circuit away from the primary piping line which typically have the pool filter. What are the pros and cons of doing it this way?

Thanks for any guidance.


IntelliFlo VSF issues

New pool owner so I apologize in advance for using any wrong terminology. Pool was originally built about 20 years ago. Recently advised by our pool service company that we ought to replace our pump due to bearings going out (it was making a very loud whining kind of noise). Previous pump was a 4-year old Pentair WhisperFlo WF26 (single speed, 3,450 rpm). Pool company provided following options: Replace existing pump motor, replace existing pump with same model, replace existing pump with IntelliFlo VSF (explained opportunities for cost savings due to variable speed / variable flow capability). We went with the VSF and it was installed about three weeks ago. We also replaced two Pentair valve actuators (on suction and return lines) and check valve internals (return lines). We previously replaced the heater (AquaCal SQ225), added a Pentair EasyTouch control system, and had the pool resurfaced.

Now to the issues. This past week we used the heater for the first time with the new pump. The heater failed with flow fault codes (I was not in town at the time; pool being used by family guests). Our guests informed our service tech of the issue (same tech that installed the pump), and he told them the heater wasn't getting enough flow and to crank up the pump speed. When they informed me of this I checked out the system remotely via the ScrenLogic app. The data indicated the pump was running at 2,750 RPM and pushing only 21 GPM. They had cranked the pump up to max (3,450 RPM) and it was only pushing 28 GPM (still not enough flow for heater; the heater requires a flow range between 30 and 70 GPM). I followed up with the service tech and he told me it is a heater issue! For the past 16 months the heater worked fine with the former pump, and given that it is a fairly new heater (16 mos) this made no sense to me, so I have been trying to figure out why there is a flow issue. I looked at photos I had taken before and after and notice that the plumbing from the pump to the filter had been changed; it is now a longer run and has an additional 90 elbow. Can this be a contributing factor? Note, the manual heater bypass valve is in the same position it was with the old pump. Any other insights as to why the pump seems to be pushing about half the GPM that it ought to be pushing at specific RPMs?

I also spoke reached out to the owner of the pool company and his response to me was that "the new pump will int be capable of reaching the published maximum GPH (I believe he meant GPM) due to the pre-existing suction and return plumbing size." I also share that this was the same pool builder that built the pool originally 20 years ago, so my follow up question to him will be why suggest a pump that can't reach spec due to existing plumbing conditions, but that's another story!




New Pool Owner // Central FL // SWG

Hi there,

I just bought a house in central Florida (Gulf side) and am a first time pool owner. I got one of the TF-100 kits and started doing tests to see what I need to do. I would love any and all advice as I get going here.

Pool Size: 13,500 Gallons (getting this from pool store file they had for previous owner and sounds about right)
Temp: 68 F
Free Chlorine: 7 PPM
Combined Chlorine: 0.5 PPM
Total Chlorine: 7.5 PPM
pH: 8.2
Total Alkalinity: 100 PPM
Calcium Hardness: 725 PPM
Stablizer: 30 PPM

- Hayward SwimPure Extreme Salt Chlorine Generator
- Hayward SwimPure Extreme TurboCell TCell925SWP
- Hayward Star Clear Plus Cartridge Filter
- Filter running 8a - 6p currently.
- Salt reading: 3200 PPM
- Percentage Generator setting: 55%

From the forums I've concluded (please correct me if I'm wrong!):
- Chlorine is high. How do you lower that? I tried turning down the generator percentage but I think it actually went up. Is this a stabilizer issue?
- pH is high. Add Sulfuric Acid (pool store sold me). Don't quite know how much to add.
- Alkalinity is a touch high. How do I lower that? Does lowering the pH raise the Alkalinity?
- CYA is low per forums but fine per manual. Please advise and help me understand discrepancy. Also looking for advice on what CYA to buy.
- Calcium Hardness is high. Drain and fill with fresh water? How much?
- Seeing as it's getting colder and I'm not using the pool much, can I turn down the filter run time, etc. to winterize?
- Is Total Dissolved Solids anything I need to track?
- Pool Store sold me algicide but I haven't used it after reading these forums and seeing that it's not needed if chlorine levels are good.

Thanks so much in advance! This has already proven to be a wonderful resource.

Pentair IC40 replacement dummy

Hi new to forum. I am living usually in Mt. Pleasant SC and other time in Islamorada Fl. I built my dream house with a gunnite pool and couldnt be happier. When its hot, the hardest decision is whether to walk the dock and go boating, or just be lazy and stay in the pool. Have a question on a chlorinator and not sure if this is the spot to post. Anyhow about how many hours are left when a "limited life" blinking green lite goes on with a Pentair IC20. I tried a 50% mix of muriatic and water to no avail. This was the first time I tried to clean it in 4 seasons of use. Should I just get another one and where would you suggest? Thanks. Ken

Boric Acid In Bulk Online

Looking for sales on boric acid today and came across this boric acid from farmer boy

the price seems great but I am wondering if this is safe for the pool as it doesnt say food grade. I have purchases from duda diesel and bulk apothecary before and the specs seem about the same but this site stats for use as a pesticide.

Research on Chlorine and cancer????

I've seen some information about potential links between chlorine in pools/hot tubs and cancer. What are the thoughts of folks about the potential risk of cancer and chlorine?

Is this only something to be concerned about at super high chlorine levels?

Is the risk in hot tubs worse (compared to pools) due to the hot water?

Do you think there is a safety benefits in trying maintain lower chlorine levels in the tub 1-2 FC and then supplement with chlorine after use? Currently I keep mine in the 1-3 FC range and add chlorine after soaks.

Thanks for your thoughts! Doug

In Ground Gunite New Build Pool/spa Leaking

Hello! San Antonio new build. Pool has been leaking since they built it. A return was cut short which created a huge leak in the yard. Pool was filled in May and leak wasn’t fixed until a month later.

After it was fixed the ground under the concrete decking was still damp.

They just emptied the spa on Friday to see if the area would dry up and it appeared the wet area initially got bigger.

Any idea why that would happen? Pressure tests shows no big leak. There is definitely still a small leak somewhere. We have lived in our house 7.5 years and our yard was never wet.

Pink denotes calcium deposit on tile that constantly is there even after acid wash.

Red denotes return that was leaking 360degrees from pipe being cut short.

Blue denotes several sections of Concrete behind and both sides of spa have already cracked. Poured in January.

Pool was started in Oct 2020 and sprinkler system has been off since day 1 of dig.

Any help would be greatly appreciated. The pool company will not acknowledge it could be their work.
Thank you in advance,


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Equipment/Valve experts thoughts please? Also we are full of water so I added some updated pictures 👍😃

This one is going to be unique, pictures of the plan and the start of the dig are attached. We can’t wait to see the final product. Any advice or thoughts please don’t hesitate to chime in…

One quick comment please disregard the mess on my Carriage House porch, we literally just moved in this past week and the pool dig started at the same time the movers were here.

Here are some pool/equipment details
- 36’ on each side, 3’6”-7’ water depth (deep part is where the color blue gets darker)
- Sun Shelf with 2 bubblers and umbrella sleeves
- 8‘ diameter 360 degree spill over spa
- 2 Fire Bowls on columns at each side of the 1/4 circle
- 3 deck jets equal distance apart on the 1/4 circle
- 5 lights, 2 microbrites on tanning ledge facing away from house, 1 in spa, 2 intellibrite 5G lights
- 400k pentair propane heater (mostly to heat up spa quickly)
- Pentair Heat Pump/Chiller
- 2 Pentair VSP
- Pentair CCP 520 Cartridge Filter
- Pentair IC60 SWG
- Intellicenter Automation
- 500 gallon propane tank

I will follow this with some finishes that are finalized…..


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Pump/ strainer basket housing does not fill with water, endlessly draining to the skimmer pipe line.

Hi all.

I am new to pool maintenance and am trying to get my Hayward Max-Flo pump to prime.

I had recently took my Pentair cartridge filter out to clean it. Once I placed it back in, my pump is not able to prime.

I am attempting to fill the pump/ strainer housing with water, but it never fills up all the way.
The water gets drained through the skimmer pipe line.

The pool is filled with water, above 50% of the skimmer. The skimmer basket is clear and cleaned.
I’ve checked the impeller and it’s clear of any debris.
The impeller does seem to spin a little slow when I manually turn it.
What’s happening with the water in my pump/ strainer housing?

Note: my pump is above the water level of my in-ground pool.
See attached pictures.
Thank you in advance!


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Need help re-assigning Aux3 on my iAqualink for my Stenner pump

I plumbed and wired up my Stenner pump this weekend, but ran into a minor snag. I hope this is just a simple programming issue...

I have the iaqualink RS-4 with a main filter pump, a second pump for the water features (aux1), lights (aux2) so aux3 should be available for my stenner pump.

My water feature pump controls both sconces and some bubblers. The pool builder assigned the button on the panel for aux3 to the valve that controls whether the sconces are on or off when the water feature pump is on. There is a 24V AC valve that controls whether only the bubblers or both bubblers and sconces are on and that appears to be tied into the Solar JVA.

There was nothing wired to the aux3 relay in the box before i hardwired the Stenner pump to it. The aux relay activates whenever the sconce (water feature button on panel / "Sconce" in app is on. There was an extra aux i renamed Chlorine Pump in the app (see screenshot from app control panel)

How do i disassociate the sconces / water feature 2 from aux3 (or can i?) and reprogram the aux3 to the chlorine pump. I want to be able to turn sconces on/off separately from the bubblers, but does that require using aux3? There's a "solar" button on the right side of the panel - can it be assigned to that?


Pool Light Timer

Hey everyone, I have a WPC-2 control box for my pool. It used to have a remote control that operated the pool light, but that gave up the ghost. I want to add a second timer to just control the pool light to come on and go off at the same time everyday. A smart timer would be even better, but I don't want to get greedy here. Anyway, I can't find another timer that looks like the other one anywhere, unless I'm missing something. According to the SRSmith manual, it's a WPCTC but when I google that, it looks like its just the time clock and not the surround that goes in the box.
This is what my box currently looks like (except some breakers on the bottom half):

Screen Shot 2021-11-20 at 9.01.37 AM.png
And I want it to look like the one in this video (or a smart timer):
Login to view embedded media
These are the timers I can find, but as you can see, it's missing the surround and cover that the one in the box has.
Screen Shot 2021-11-20 at 9.06.19 AM.png

Can anyone help me with this?

Electric Heat Pump Pool Heater Recommendations?

I have an outdoor (no screen enclosure) 60 feet long by 11 feet wide lap pool in my backyard, 30,000 gallons, salt water. In west-central Florida (Tampa Bay area). I want to be able to heat the pool during the winter months. I have looked into the traditional pool solar panels (roof mounted) where pool water is pumped through them to heat the water, but seems like the rule of thumb is you need the same surface area of your pool (or more) of panels, so I would need at least 660 sq ft of panels on my roof which seems like a large amount. Unless there are some kind of newer technology panels that are way more efficient and therefore would require less panels?

As an alternative solution to explore, I would like to look into an electric heat pump pool heater. My pool is 30,000 gallons so would probably require a large unit (if they even make them that big). I'm interested in determining what manufacturer makes the best quality units? I wonder if someone makes electric heat pump pool heaters for commercial pool applications? I understand that they use electricity (unlike roof mounted pool solar panels), but I'm also looking into the possibility of a Tesla Solar Roof (electricity generating) to generate the electrical power to run my house, which could potentially run a new electric heat pump pool heater also. Currently I have an older concrete tile roof on my house that I'm not a big fan of, tiles crack due to thermal expansion, attracts black algae which needs regular cleaning, has some leaks, etc, etc. I would not want to mount pool solar panels up there without first replacing the roof (with shingles.....no more tile).

Any recommendations on who makes the best quality residential (or commercial) electric heat pump pool heaters? Or any other thoughts on my crazy ideas? Any thoughts appreciated! Thanks!

Help Picking Tile Grout

Hi All,
I need some help picking my tile grout color please. I am in love with my tile, and wanted a seamless look. The pool builder who is helping us finish (after we fired the original PB) told me to use just plain white because it wouldn't get stained and was easy to keep clean. The tile was installed and grouted last week. I am not happy with the white at all. We are looking at having the tile setter remove the white grout and re-grout the pool. I need color suggestions please!!!! I know that @kimkats is the resident bling queen and I am definitely after some bling here! I am attaching pics of the tile, tile installed without grout, and then the white grout as it is now. Thanks in advance!


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Booster pump housing leaking

Moved from here.
Googled the term PB4 SQ housing leak and found this forum. I'll have to say this is definitely a QC problem from this manufacturer as I have a leak in the exact same spot, Plus, a new leak at the top of the housing has developed. Seems the material used is completely defective. This was a replacement for the pump that was affected by the North Texas deep freeze, so much less than a year old. Hopefully Polaris, will do the right thing and replace the entire unit. The pool maintenance company that installed it says it should be covered by warranty.

Pump Anomaly

Had an odd experience recently with a replacement pump, if anyone could shed light on why the following occurs I would be grateful.

My 10 yr old Viron P320 pump started making whining noises, the last time it did this 3yr ago cost me $450 to get it serviced where they replace the bearings and mechanical seal as well as cleaning up the pump internals. This time I thought I'll just get a new pump.

I was recommended to purchase the new model of my pump which is called the Viron P320 XT. It was a direct replacement plumbing wise with all the connection points being same position as old one. The new pump is AC variable speed where as the old one was DC, new pump motor end is smaller and lighter than old.

When I started up the new pump it took a while to prime but did not fully prime with a small pocket of air less than 10mm high remaining in the basket chamber. I ran the pump on high for ages but it would not pull the air out, I could not see any air bubbles inside the chamber. I did some googling and tried the following:

1. Put cling film around all the joints and coupling to see if they sucked in.
2. Swapped the lid from old pump to new.
3. Doubled up the rubbers on the lid.
4. Adjusted the pump suction collar until I could see the point where bubbles entered and then did it back up again.
5. Adjusted both drain valves until I could see air bubbles coming up from them then did them back up again.

It didn't look like a suction leak, unless it was the lid fitting sucking air in from the top. I put the old pump back in as it still worked, just makes a horrid sound, and it primed quickly as normal and got rid of all the air. I then put the new lid on the old pump but it still worked ok.

I called the place I got the new pump from and they fobbed me off to Astral, the manufacturer. On the phone they agreed pump was faulty and the seller should swap it, contacted seller and they called me back saying the had arranged a service call out from Astral. The tech from Astral stripped the pump down looking for anything and regreased/assembled pump and it did same thing. We then went thru parts of the aforementioned fault finding and he was stumped and said seller should swap it over.

I contacted seller and they agreed to swap pump. Got the new pump and connected it up and does the same thing. I have tried running the pump at medium and slow speed and it the water level in the basket does not vary, still always that last little air pocket in basket. So it doesn't look like there is a danger of it running dry as there doesn't seem to be suction leak and there is certainly no pressure leak.

Can a pump just not have the power to evacuate all air from the basket?

DIY Pool Maintenance in District 12 (Viet Nam): a harrowing tale

Thanks to COVID I was "stuck" in Hoi An, Viet Nam for 20 months (good place to be stuck), and as the only tenant in a 6-apartment building (a typical scene as tourism is decimated across Vietnam, Thailand, and all of South-East Asia) I took on the role of maintaining (and enjoying) its pool. Thanks to this forum and many YouTube resources I gave myself a crash course in pool maintenance that was mostly successful.

Since other expats will likely run into the same situation (especially with world-wide COVID tourism collapses) I decided to write up my experiences trying to learn and practice DIY pool maintenance in a part of the world that has NO decent test kits of any kind (not even close to TFP's recommendation), NO pure bleach, NO CYA at all, and truly scary standards of pool safety knowledge and attitudes, even by the so-called "professionals."

Hope you all will get a good laugh out of this, and maybe a few of you living in other District 12s around the world can use the info too...

Wondering if anyone has additional MacGyver-style ideas about how to usefully measure pool chemical levels with very very limited equipment, in the same light as my efforts here:

Test Kits are NOT Made Alike!

Also I never quite figured out this conundrum about how an infinity pool's tank is actually supposed to work; reasoning about the two tanks is actually quite a brain puzzle. Curious if anyone has ideas:

Reasoning about the Infinity Cave Reservoir

Thanks again to all of you who wrote great blog posts and offered great advice!

Need help selecting a new pump

I'm considering replacing my Hayward Northstar 2HP pump as I'm having difficulty sourcing some parts to repair it. It feeds an older stainless American Titan 60 sq. ft. DE filter, 2" PVC pipes. About 20,000g in-ground pool. There is a spa with a waterfall into the pool on the same pump. Current pump is wired on 240V on an old-school Intermatic mechanical timer. Not too concerned about energy efficiency as we have enough solar to offset a 2HP single-speed pump running 5hrs a day. I'm in CA so as far as I understand higher power single-speed pumps are no longer legal here. So basically all I need is an inexpensive reliable pump that I can limp with through until I'm ready to redo the pool and the equipment in 5-6 years time, that's the plan anyway. Any suggestions?

Random spot for mineral deposits

Hi all! Could there be an easy explanation for mineral deposits on the split face in the raised in ground spa? We have had so many issues with our pool. I can see water dripping very very slowly. This area does not get and splashing.

Thank you!


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Jandy JXi 400 - Igniter Problems

Had the unit installed 10/28/2018, no issues except for having to replace the Thermal Regulator Valve about 6 months ago (rusted shut)

Now 2 weeks ago: Got a fault: CHECK IGN STEPS
  • Found the igniter element was broken
  • Replaced with a new igniter, worked fine for one day, then the new igniter element broke
  • Replaced with another new igniter, worked for 3 days, then this new igniter element broke.

Freezing temperature and heat pump

Hello all.

I began winterizing our inground pool last week end but did not have the time to complete.
So last weekend, I lowered the pool level below the returns and shut off the pump, leaving the cap of the pump off.
Temperature was mostly above 0C (32F) all week, with some times during the night below freezing point.

I finished the winterizing today by blowing the pipes, adding antifreeze, capping the returns, emptying the sand filter and disconnecting all those flexible tubings.
However, water started freezing between the filter (in a shed) and the heat pump outside. And the temperature will continue to go down (currently -5C / 23F).

I'm going to place a mobile electrical heater next to the pipes/heat pump to be sure the water doesn't deep freeze and expand so I can finalize tomorrow.

But, I'm curious about something: would re-powering the heat pump help ? I know there are sensors but if the compressor starts, it should create heat and help keep the water in its pipes from freezing and bursting. Any thoughts ?


External Control of Max-E-Therm, relay - 2 or 3 wire, how does it work?

Hi All,

I'm currently building a custom pool controller using some relays, and I'm trying to figure out the best approach to the Max-E-Therm 400 that I have. I'm reading the documentation and I can do either a 2 wire or 3 wire install. The 2 wire requires the use of the firemans switch (from which two wires then go to the external control interface) and this part gets confusing to me, the 3 wire does not? If it does not then can I just apply 24v AC to the spa side or pool side? If thats the case then would the heater then just use whatever the max is set to for that type or would I just need to just turn off the heater when the pool or spa temp hits a certain temp?

If anyone has any idea its greatly appreciated.