Automate acid dosing with ET

[losgatosgtr]

Hello Dirk, Brian, Jim,

My IPH controller crapped out a while ago so I decided to wire up a 24-volt power supply into the AUX 3 relay on my easy touch powered by an AFCI breaker I added to my panel. I named the relay "ACID PUMP" and set the function to Generic. I can manually press the AUX 3 button to switch the IPH pump on and off no problem. I also have an IC60 chlorinator that is plugged into the easy touch and I am happy how this is controlled. When the IPH controller was working it ran once per hour set at 100% based on the acid consumption of my newly remodeled pool and on me running my pool pump for 12 hours. My dilution is 2 parts acid to 1 part water. I believe if the IPH controller is set to 100%, it runs for 60 seconds each hour. Is that correct? That equates to about 11 or 12 minutes per day of total IPH run time.

My question to you guys is this:

In an ideal world I want to automatically turn the IPH pump on, a few times per day, to provide the proper acid dose (11 minutes total of IPH run time) for my pool. The IPH pump run time could be adjusted up or down to regulate the amount of acid delivered to the pool.

Ideally this strategy would deliver the acid in smaller doses throughout the day during the pool pump run time. My pool is scheduled to run from 7 AM to 7 PM right now.

Is this multi dose per day scenario possible to accomplish using the easy touch schedules, egg timers, etc?

Is doing this overkill and should I just run the IPH pump once per day for 11 minutes? I'm kind of worried about the pump overheating if it runs for 11 minutes straight, but I'm not sure if this really matters.

Someone also mentioned an egg timer and that it would be a good idea to have this set up properly so if the IPH got switched on by accident it would only run for the length of the egg timer as a safety measure.

Any help and support would be much appreciated.

thanks,
Scott

 

[Dirk]

I'll leave the ET programming to Jim. But he could probably use your ET model number to better answer your question.

I like the fact that my IpH dispense a little acid many times a day, rather than all at once. I think it is better for the pool finish not to spike pH. That said, that is probably more applicable to dosing once a day rather than once a week. As long as your pH is not moving drastically with each dose, the sum effect on your finish probably won't be much, if any.

More importantly (at least I think it is important), one of the nicest features of the IC/IpH combo is that the IpH controller shuts down the IC while the IpH is pumping acid. Pentair recommends placing the injector in front of the IC. This send acid through the IC (and perhaps keeps it nice a clean?). But the IpH only does that when there is no chlorine in the IC. If your IpH is going to pump acid into the IC, while the IC is producing, I can't imagine that is a good thing. It might even be bad, possibly really bad, since MA + chlorine produces a very toxic gas. I couldn't say if that would make it out the returns or not. It's something to be aware of, at least.

To avoid this, you could program your acid injection first thing, then turn on the IC after that. Or do that multiple times a day if your ET has the available schedules. So 5 minutes of IpH, then a few hours of IC (then off). Then 6 minutes of IpH, then turn the IC back on for the rest of its runtime. Something like that.

I don't remember exactly how the dosing happens for the IpH. I do remember there are some tables in the manual about it. You might be able to find what you're looking for there, regarding how much acid is going in per hour.

 

[mknauss]

I moved this to its own thread.

 

[mknauss]

If you had a valve actuator slot available in the ET, why not use that for the 24VAC supply? You would not need to use a relay then, just add a Feature Circuit.

EDIT. My bad. I missed the 24 VDC for the dosing pump. My mistake.

 

[Jimrahbe]

Scott,

You can set up several schedules to turn on your ipH a number of times per day.. But... The key is that a standard EasyTouch only has a max of 12 schedules and that includes any egg-timers not set at 12 hours and any run-once programs.

I just don't see any advantage of dosing several times a day vs. once a day.. Let's face it, those of us that do not have a acid pump are most likely dosing once a week...

If this were my system I would maybe have it dose twice a day..

An egg-timer is used when you manually turn something on and want it to automatically shut off.. Most schedule have a start and stop time, so you don't really need an egg timer.

Thanks,

Jim R.