So I've decided to leave the tech business and start a pool services company, this is my first post of several in a series of related topics. Just kidding, but I did install a new salt water chlorine generator (SWCG) for my pool and here's what was involved. I've had an ailing Pentair IC40 for five years now that worked ok the first year I had it, but then it was nothing but trouble thereafter. Three flow switch replacements at $75+ each, constantly pouring in bleach to augment and this year, yet again, after removing the cell for the winter, when I reinstall it comes up red, system off, again. This means one of four things: water temp too low, salt too low, bad flow switch or bad cell. I'm betting the last as these things aren't really expected to survive more than 2-3 years, so my cell probably died over a year ago. Sadly, Pentair only offers an abysmal 1 year warranty on these units (60 days if you install yourself), which at the price of admission, is completely unacceptable. I set out to replace my bad Pentair solution with something better.

Disclaimer: As is always the case, anything presented here is for informational purposes only. 
Anything you choose to replicate is at your risk or peril, not mine. If you have no experience 
with plumbing or electrical work this is probably not the project for you!
 

So, why salt water?

Many confuse why people convert their pools to salt to begin with and what that really means. There's a couple of very good reasons: easier maintenance and easier on your body. Salt pools still require Chlorine (CL) but instead of using feeders, pucks or liquid CL, the sodium chloride in the water (NaCL) is converted to sodium hypochlorite aka Chlorine (NACIO) with the help of an electric salt cell as the water passes through it. The CL does its job destroying organics and returns to the water as salt when exhausted where the process repeats. The process is simple, renewable and cost effective. Salt pools require much lower CL levels overall (3-5ppm) and leave your skin feeling soft without the eye burn that comes with traditional CL pools. Your water chemistry still requires balance of course with a special consideration paid to PH, which will steadily creep upwards if unchecked, and calcium hardness. Calcium scaling is the enemy of salt cells which reduces the cell's effectiveness and life over time. You'll often see thin slivers of calcium on the pool steps or floor as the salt cell performs its "reversing" procedure to clean itself of scale buildup. There are of course a number of options that can be used to sanitize your pool, each with its pluses and minuses. Here is a short list of options from my research and practical experience from maintaining a pool for many years as well as why I settled on a replacement salt system. 

 

Chlorine Tablets (Pucks) - This is the most common method used via floating dispensers or automatic in-line feeders. While it's easy to stack a few pucks in one of these delivery products  and forget about it, the problem with this method is that these pucks contain additional chemicals besides CL, namely cyanuric acid (CYA) aka stabilizer. CYA is important to have in the pool to protect the CL from being destroyed by sunlight, but there is a specific balance to maintain. Pucks keep feeding CYA which keeps building in the water, finally to the point that the CL can no longer do its job. Algae starts building and you wonder why. The only way to get rid of CYA is to drain and refill.

 

Liquid Chlorine - Most commonly known as bleach, liquid CL is the purest and most beneficial sanitization method available for the pool. Varying concentrations can be found from 8.25% to 10+% but it's all the same stuff: bleach. The only problem with this method is having to constantly stock, store and add bleach to the pool. Slip up because your stock is low and you could be fighting an algae outbreak in no time. Contrary to what the pool store will tell you, you don't need to buy "special" chlorine nor shock for your pool. Bleach is all that you need.

 

Liquidator - Pouring bottles of bleach in the pool, while effective, is a hassle, enter the Liquidator (LQ). The LQ is a simple device that is used to passively add liquid CL to the pool using gravity and the suction side of the plumbing. Liquid CL is mixed with pool water in an 8 gallon tub that causes the heavier CL to sink to the bottom below the pool water. When the pump runs the liquid CL is pumped into the pool and chemical odors are kept at bay. The LQ is fairly cheap at $200 for the equipment plus the cost of bleach to maintain. The problem with this method is fine tune control of how much CL you add to the pool and keeping the tank filled with the CL kept cool. I've read recently of people having trouble with mineral build up in the LQ equipment causing them to abandon this solution completely.

 

Stenner - Stenner pumps have been around for ages and provide another method to get liquid CL into the pool but via an active pump, so there are no issues with mineral build up on the stenner side. Most use a 15 gallon tank, filled with bleach, and a 100PSI pump set to run on a timer to add CL to the pool when the main pool pump runs. Most are very happy with their Stenners but the issues with this solution are getting the right parts to build the pump and tank, storing CL which degrades when it gets hot and the cost/ hassle of keeping the tank filled. While the Stenner may be cheaper to build initially (~$400), the annual cost of bleach puts this as a potentially expensive solution depending on the number of active months in your season. The average I read was consuming ~15 gallons per month during the summer, which at $4+ per gallon adds up year after year.

 

SWCG - So here we are, back at the SWCG. I outlined the benefits in the first paragraph which center around ease of maintenance and body friendly properties. Buying into the SWCG solution is one of the more expensive options and will set you back at least $1K plus salt which is $5-10 per bag. After the initial investment, if all goes well, you'll be on easy street only having to adjust your salt after heavy rains or being closed for the winter. But, assuming this solution lasts for a minimum of 3 years, which is the warranty period of the Hayward AQR15, it is still cheaper than the Liquid CL methods in the long run. Problems can and will occur, however. The most likely issues will be failing flow switches, bad control boards and salt cells that require replacing, all of which should be covered during the warranty period if any of that were to happen. Once the cell has lived its useful life, the replacement for this particular model is ~$450, half of the initial investment, which would last another 3+ years.

 

More information on all these options including proper water chemistry and other pool basics can be found at my favorite online pool resource: troublefreepool.com (TFP).

Installing the Aqua Rite 15

The AQR15 is a fan favorite at TFP with many claiming years of faithful service well past the warranty period. Having done the math on the other options and ruling out the LQ and Stenner due to cost, I finally decided the AQR15 was the right move. After having such a rough go with the Pentair SWCG I was extremely hesitant to invest in a new setup which is not a cheap entry to market. $1000 will get you a salt cell and a control box/ transformer. The general rule of thumb for pool equipment is to "go bigger" than you need to. This mainly applies to filters and SWCGs as it is possible to go too big on the pump depending on the size of your pool. The AQR15 is a kit that includes: a flow switch mounted to a 2" slip-fit T union, a T-15 cell (chlorinates up to 40K gallons) and the control center that monitors each of these components while being able to provide useful metrics such as water temperature, water salinity and cell voltage/ amperage.

 

Here is the desired before and after design. The Pentair IC40 is a simpler product with the flow switch integrated into the cell housing using a single cable to connect to the transformer. The AQR has an external flow switch which requires 12-inches of straight pipe upstream from the switch but placed after all other pool components (filter, heater etc). If placing the flow switch after the T-15 cell, the cell itself serves as the required 12-inches. Both the flow switch and the cell must be wired to the control box individually.

First step is to modify the plumbing to accept the new Hayward components, which requires me to elongate my existing return loop. You always want to try and leave 2-3" of pipe, minimum, in your plumbing for future modifications. You'll see there are a few spots where I am now out of room. Any future updates will require me to rebuild larger downstream valve junctions and these Jandy valves are $50 each. I made cuts with my reciprocating saw to remove the existing Pentair couplings which, unfortunately, did not match the thread pattern of the new AQR and had to be replaced. I glued in the new flow switch and built the downstream side of the cell couplings as you can see below. Pay special attention to the direction of the flow switch whose arrows are on the top of the unit itself.

Next I built the other side of the cell coupling trying to elongate this section as little as possible. Any length I add here will have to be replicated to the upper section of the loop. After installing the cell I was able to cut the upper portion of the loop and elongate using a single 2" coupler. I got lucky. I was prepared to have to add a new section of pipe here with 2 couplers but that proved unnecessary. The cell can be installed in either direction since the flow switch is external to the cell. Don't forget to lube the O-rings of the cell couplings. Here is the new cell plumbed in (with my helper working on the bonding wire):

 

While the glue sets on the plumbing, on to the electrical portion of the install. The Hayward control box is much bigger than Pentair's, so while I was able to reuse 2 of the existing mounting screws, I needed to drill more. Drilling through brick sucks, it just does. I have my SWCG control box mounted above my timer and already have weatherproof conduit in place. Remove a knock out from the bottom corner of the new control box and shorten the wires to the appropriate length. Secure the conduit to the new box. The control box comes preconfigured for 240V setups which will be most common in larger in-ground pools. 2 x 120v hots plus a ground with the 2 middle connections of the box jumpered. Pretty simple. Make sure the breaker is off before you start fiddling with wires, 240v is not something to play with. Because my Pentair VS pump has a built-in timer, I have to use a separate timer to run my SQCG and heater or invest in a very costly automation system. Have I mentioned that I don't like Pentair much anymore?

 

With the power supplied to the control box, all that remains is connecting the bonding wire, flow switch and salt cell.  The previous idiot that installed my Pentair system used the wrong kind of wire for bonding which isn't safe or to code. Code calls for 8 AWG copper and should connect to the exterior of all pool equipment that carries an electrical charge. The bonding wires of all components connect together and then run into an earth ground. This is to eliminate the risk of shock should any of these pieces become electrified. Here my helper is connecting our new bonding wire to the junction next to the pump.

 

The bonding wire connects to the exterior of the control box via screw mount and the flow switch connects using an RJ11 connector pre-assembled.

 

Before you connect the salt cell to the front of the control box, the proper model number needs to be entered in the control box first via the diagnostics menu. There are stickers everywhere warning you of this so best to take heed. By default the largest cell available, the T-15, is programmed. If you have a smaller model, change this first before supplying any power to the new cell. Once everything is wired, glue dry and proper cell configured, the system can be tested assuming you already have the proper salt level in your pool. If you do not have any salt yet, add this first and wait 24 hours before powering the new cell. The proper amount of salt plus other pool chemicals can be determined by using the pool calculator. Otherwise, set the desired % of CL output, set the cell to Auto and watch for green lights and power and generating. Expect a period of 'dialing in' while you figure out what output percentage and run times are necessary. Success!

 

 

Here is everything installed. So far very pleased with the setup.

 

Key Takeaways

• Go bigger than you think you need to with pool equipment. A bigger SWCG means that it will do the job at a lower percentage of output which is great if you really need to crank things higher for short periods of time.
• Plan your plumbing. A SWCG can be easily plumbed into a new or existing setup. Keep in mind that the Hayward AQR has an external flow switch that requires 12-inches of straight pipe in front of it, placed after all other pool equipment on the return side of the plumbing.
• Use clear PVC primer for a cleaner finish. Nothing wrong with the purple stuff but clear is cleaner.
• The Hayward T-15 cell can be mounted in either direction since the flow switch is external. Hayward encourages changing the direction after 3-month inspections or cleanings.
• Bond your equipment with the proper 8AWG copper wire.
• Make sure the control box is programmed with your particular cell before you supply power to the cell!
• Time your cell to operate while the main pump is running only via timer box. Do not use the operation of the main pump to control the timing of the SWCG operation.

 

Resources

http://www.troublefreepool.com/

Pool School

The pool calculator

Aqua Rite Operation and Installation Manual