How to Convert a Pool to Salt Water

Can you convert a chlorine pool to salt water?

Yes, and the water stays where it is. We read the manuals from Hayward, Pentair, Jandy, AutoPilot, CompuPool and Solaxx, and not one asks you to empty a chlorine pool first. That is an absence across those documents, not a line any maker prints. A drain is only the cure for a reading that is out of range: salt, calcium hardness or cyanuric acid that is too high, or nitrates.

A salt pool is still a chlorine pool. Hayward and Jandy describe one loop: the cell turns dissolved salt into chlorine, the chlorine kills bacteria and algae, then it goes back to salt.

What a salt system is, and what comes in the box

Three parts: a control or power center that turns house current into low voltage DC, a cell that makes the chlorine, and a flow switch or sensor that stops the cell when water is not moving. Several makers sell the power supply apart from the cell.

Fitting an IC20, IC40 or IC60 to a pool that never had one? Add the PC100 Power Center.

What size salt system does your pool need?

Buy for the gallons in the pool. These are the makers' own ratings, with chlorine output per day.

Pentair's guide prints 30,000 gallons for the LT25, the PLUS30's figure, while the cell's own listing rates it for 25,000. Hayward's product page for the T-CELL-15 shows 1.45 in a field labelled Salt (lbs/day), a figure no manual repeats. CompuPool's ratings change with the document: the CPSC36 is 40,000 gallons on the USA brochure, 35,000 in the Australian manual.

• Jandy's general rule: a pool near the maximum size, used year round in hot water, may call for a larger generator or a second unit.
• Solaxx's Resilience footnote: the 40,000 gallon figure assumes cyanuric acid, and warm climates, heavy bather load and lap pools call for a larger model.
• Hayward: silent on oversizing. Its warranty excludes installation on a pool larger than the rating.

For a 40,000 gallon inground pool the complete Hayward system is the AquaRite W3AQR15. The W3AQR9 covers 25,000 gallons, the W3AQR3 15,000, and the AquaRite S3 AQRS340 runs on anything from 1,200 to 8,000 ppm of salt. Shop all salt chlorine generators.

What to check on the pool before you buy

Pentair calls salt inherently corrosive. Check what the water will touch.

• Salt already there. Hayward, Pentair, Jandy, CompuPool and Solaxx all say to test first.
• Metals and nitrates. Hayward and AutoPilot want metals at 0 ppm. In water that is not new, Hayward asks for a quart of metal remover and a quart of non-copper algaecide. Solaxx says nitrates mean a partial or full drain.
• Calcium hardness. Jandy's TruClear XL manual wants 200 to 400 ppm and stops the install at 800 ppm or more, because the cell scales fast and fails.
• Stone. Hayward sends owners of natural stone coping or decking to a stone installation specialist first, and its warranty excludes degradation of natural stone in or beside the pool. Jandy says to seal all masonry.
• The heater. Heater makers cap salt: Hayward's Universal H-Series and Pentair's MasterTemp at 5,000 ppm, Raypak at 4,500.
• An automatic cover. Cover-Pools says aluminum cover parts on a bonded salt pool can show galvanic corrosion inside two to three years.
• Ladders and rails. Jandy wants every metal part to be high grade stainless steel. S.R. Smith lists a zinc anode as rail protection, without naming salt pools.

No salt system maker we read recommends a sacrificial anode. Solaxx has an installation sheet for an anode tee that makes no claim for it. A 2 in inline anode is a part you can add, on your own judgment.

On biguanide: none of the manuals we read covers the change, so we print no procedure.

Where the cell goes in the plumbing

In the return line, after the filter and the heater. Pentair's MasterTemp manual gives the reason: a check valve between heater and chlorinator stops concentrated chemicals siphoning back. Hayward's H-Series manual and Raypak ask for the same valve.

• Hayward AquaRite: after all the equipment, on 2 in PVC, with at least 12 in of straight pipe ahead of the flow switch. No minimum flow is printed.
• Pentair IntelliChlor Plus and LT: 3 ft or more from the heater's outlet, behind a straight run of 12 to 18 in. Vertical is preferred, flow going up and cord pointing down. Laid flat, the control panel faces up. Flow is 25 to 105 gpm, with a bypass loop above 80. The iChlor starts at 20 gpm.
• Jandy AquaPure: the common line after the heater, horizontal or vertical. No gpm figure is printed.
• Jandy TruClear XL: last before the pool, upright on a pipe within 10 degrees of level, never on a vertical pipe. 30 gpm minimum.
• AutoPilot ChlorSync: horizontal, 20 gpm minimum, a bypass kit above 80 gpm. The Pool Pilot Digital manifold is vertical only.
• Solaxx Saltron Reliant: ahead of any tees in the return, horizontal or vertical. No gpm figure is printed.

Pentair puts an in-line tablet feeder downstream of the cell. So "the cell goes last" holds for a TruClear XL and fails on a Pentair pad with a feeder.

The wiring, and who should do it

One rule is shared: the cell has power only while the pump runs. PHTA says a generator makes hydrogen gas and must be electrically interlocked with the circulation pump, with the flow device as secondary protection. Check, clean or replace a flow switch. Never defeat one.

• Hayward AquaRite: powered from the pump timer's load side, to local and NEC codes. It ships set for 240 VAC and converts to 120. Bond it with 8 AWG copper.
• Pentair: only a qualified professional should install and service it. The power center goes on the load side of the pump timer, relay or automation system. Its guide calls a GFCI protected circuit for the PC100 recommended, not mandatory. Local code decides.
• Jandy: requires a licensed electrician for all electrical work. The AquaPure is fed off the pump relay's load side, factory wired for 240 VAC. The TruClear XL must be on a GFCI protected circuit.
• AutoPilot ChlorSync: a licensed electrician or certified electrical contractor should make every connection, on a GFCI protected circuit, 10 ft or more from the pool wall.
• Solaxx Saltron Reliant: a licensed electrician must do the electrical work, on a GFCI protected circuit of 6 A or more.

Start up, in order

1. Balance the water. Hayward wants the chemistry in balance before the unit is switched on.
2. Raise chlorine another way where the maker says so. AutoPilot wants free chlorine at 2.0 to 4.0 ppm before a ChlorSync starts, since it is built to maintain, not to shock. Pentair shocks when demand is high and waits for 2 to 4 ppm. Jandy shocks and waits for 1 to 3 ppm.
3. Test the salt already in the pool.
4. Add salt with the pump running. Hayward asks for sodium chloride over 99% pure, Pentair for 99.8%. Pentair, Jandy and Solaxx keep it out of the skimmer. Jandy sets output to 00% first, and CompuPool turns the chlorinator off. The pool salt calculator gives the pounds.
5. Brush and circulate. Hayward, Pentair and Jandy all say 24 hours.
6. Verify the reading. Pentair checks it on the cell and with a separate test.
7. Switch the cell on, after the wait in your system's row.

Salt, stabilizer and the wait all change with the system. Use the row for yours.

New plaster waits before salt goes in: 10 to 14 days by Hayward's manual, a month by Pentair's, 30 days by Jandy's and AutoPilot's.

Above ground pools

Buy a system built for one.

• Hayward AquaTrol: rated to 18,000 gallons above ground, with its own pump timer. The return jet model hangs the cell straight down below the return jet and plugs into a GFCI receptacle.
• Hayward Salt and Swim SAS-ABG: up to 23,000 gallons, return jet mounted, on a 120 V cord.
• Solaxx Saltron Reliant AG: 20,000 gallons on Solaxx's product page, 25,000 in its brochure, 1.15 lb a day in both.
• Solaxx Saltron Retro: hangs on the pool wall with no plumbing. 0.4 lb a day, for pools to 20,000 gallons.

Pentair says not to use the IntelliChlor or iChlor with storable or steel pools. Jandy keeps the TruClear XL to permanent pools, and Hayward bars the Salt and Swim 3C from above ground pools. We found no other maker statement on steel walls or frames.

After the conversion: what the routine becomes

The generator makes chlorine and does not measure it. Pentair and AutoPilot both say so, and PHTA adds that it supplies no stabilizer. You still test.

• Testing. Pentair: pH, alkalinity and free chlorine weekly; salt, cyanuric acid, calcium hardness and metals monthly. Jandy AquaPure: chlorine, pH, alkalinity and hardness daily, salt and stabilizer monthly.
• Inspecting the cell. Hayward every 3 months, Pentair at least every two, Jandy AquaPure monthly at first, CompuPool every six months, Solaxx monthly. PHTA says scale forms even in balanced water. See how to clean a salt cell.
• Topping up salt. Hayward says salt leaves through splashing, backwashing and draining, never by evaporation.
• Wear. PHTA notes that every acid cleaning, and polarity reversal too, takes life off a cell. See when to replace a salt cell.

What a conversion consists of

We print no cost figure. It is six things:

• The system: control or power center, cell, and flow switch or sensor.
• Salt. From zero, Hayward's chart puts 267 lb into 10,000 gallons to reach 3,200 ppm, and Pentair's 300 lb to reach 3,600.
• A salt test, such as the AquaChek salt system test kit.
• Stabilizer, if the pool sits under your system's range: cyanuric acid in a 5 lb pouch.
• Fittings: adapters for 1.5 in pipe, and a check valve where there is a heater.
• Labour: an electrician where the manual requires one, and a plumber if you do not cut pipe yourself.