Hayward AquaRite 900 vs. AquaRite S3: Which Salt System Should You Buy? (AQR940 vs AQRS340)
Two Hayward salt systems keep landing in the same shopping cart argument: the AquaRite 900 (AQR940) and the AquaRite S3 (AQRS340). Both are sized for pools up to 40,000 gallons. Both turn dissolved salt into chlorine so you stop hauling buckets of tabs around. They are not the same product though, and the difference is bigger than the price gap suggests.
Short answer first. The AQR940 is a salt chlorinator and that is all it does. The AQRS340 is a salt chlorinator that also runs some of your other equipment from its own screen. Here is what that looks like out at the pad.
What is the difference between the AQR940 and the AQRS340?
The AQR940 makes chlorine. The AQRS340 makes chlorine and gives you basic control of your heater and your variable speed pump through a color LCD display. That is the core split.
The AquaRite 900 platform, which the AQR940 belongs to, ships with Hayward's Extended Life TurboCell (the TCELL940 in this size). Hayward rates that cell to produce about 25% more chlorine over its lifetime than the cell on their standard AquaRite systems. If your only goal is sanitizing the water and getting more years out of the cell, that is the pitch.
The AquaRite S3 in the AQRS340 goes a different direction. It has a clear TurboCell so you can eyeball scale buildup without pulling the unit apart, it runs across a wide 800 to 8000 ppm salt range, and it has auto voltage select so installation is less fussy. It also has an upgrade path: if you decide later you want app and web control, the AQRS3OMNIKIT converts it to Omni.
Does the AquaRite S3 replace a pool automation system?
Not entirely. The AQRS340 is the standard S3, not the S3 Omni. You get on-site control of chlorine output, heater functions, and a variable speed pump from the display at the equipment pad. You do not get phone app control, valve actuator control, or lighting control out of the box.
People mix this up constantly. If you were expecting to change your pump speed from the couch, the AQRS340 by itself will not do that. Single speed pump control is possible but it needs the Smart Relay, which is a separate purchase.
Which one is right for a 40,000 gallon pool?
Both are rated for 40,000 gallons, so pool size does not decide this one. What decides it is what else is sitting on your pad.
- You already have EasyTouch, OmniLogic, ProLogic, or another controller running your pump and heater: go with the AQR940. Buying automation twice is a waste.
- You have no automation at all and a variable speed pump you currently set by hand: the AQRS340 earns its keep, since it takes over pump and heater duty.
- You want the longest cell life and the fewest moving parts: the AQR940 with the Extended Life cell is the simpler machine.
- You think you might want full app control in a year or two: the AQRS340 leaves that door open through the Omni upgrade kit.
Is the AQR940 or the AQRS340 cheaper?
The AQRS340 lists lower than the AQR940 at our current pricing, which surprises people. The extra money on the AQR940 is buying cell longevity, not features.
Think about it over five or six years instead of at checkout. A salt cell is the part you replace, and replacement cells are not cheap. If the AQR940's Extended Life cell buys you an extra season or two before you need a new one, that gap closes fast. If you would rather have the control features today, the AQRS340 makes more sense.
What about warranty and long term support?
Hayward backs the AQR940 with a 4 year limited warranty. Both units are current Hayward product, so parts and cells are readily available, which is not something you can say about every older salt system still running on pool pads today.
One habit that helps either system last: check your salt level and your stabilizer before you blame the box. A salt system that suddenly stops producing chlorine is usually reacting to water chemistry or a scaled cell, not a failed board. Clean the cell on schedule and both of these will treat you fine.
Still stuck between the AQR940 and the AQRS340?
Pick the AQR940 if you already have automation and you want the best cell life you can get. Pick the AQRS340 if the salt system is going to be the brain of your equipment pad and you want heater and variable speed pump control built in. Neither is a bad buy for a 40,000 gallon pool. They just solve different problems.
Hayward | AQR940 | AquaRite 900 Salt Chlorinator with Extended Life TurboCell | 40,000 Gallons
$2199.99
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Hayward | AQRS340 | AquaRite S3 Salt System | 40,000 Gallons with Basic Automation
$1850.00
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