IC60 flow light turns red after 10 to 50 minutes

[npkr01]

To his credit, my PB finally changed out my IC40, which based on prior post a couple of weeks ago, was probably undersized or malfunctioning (I could never get any chlorine reading at all unless I left it on 100% for several days in a row).

At my request (and based on some feedback from this forum), although he still felt that the IC40 should be adequate, he installed an IC60 in it's place. However, since installation about 5 days ago, the red flow light goes on anywhere from 8 to 49 minutes after startup of my pump when it is on low speed (I timed it several times). The flow light is green and stays green if it is on high pump speed. The IC40 always had a green flow light on low speed up until the moment it was removed and the IC60 installed.

The IC40 and IC60 have identical listed flow requirements, so this doesn't make sense to me. If the IC40 had adequate flow on low speed, the IC60 should as well. Also, why would the flow light stay green for 30 or 40 minutes or longer, indicating adequate flow, then change to red? It would seem that if flow wasn't adequate, the flow light should turn red immediately after startup on low speed.

The only potential problem I can see is that the pipe leading into the intellichlor is directly off a "U-turn" (2 90 degree turns separated by about 10 inches of pvc) in the PVC- it is only about 2 inches from the turn to the inlet of the IC60, rather than the recommended 12 to 18 inches of straight pipe. However, this would not explain why the IC40 flow was adequate on low speed while the IC60 gets a red no flow light. The location/configuration of installation has been the same for both Intellichlors.

To me, it looks like I got another bad Intellichlor which needs replacement or at least a new flow switch. What do all of you think? Any comments or suggestions? Thanks in advance.

 

[CraigMW]

It could be that the flow level on low speed is just enough to actuate the pressure switch in the IC60. The flow switch on the IC40 might have been a bit more sensitive to flow than the current IC60. I have a variable speed pump, and I've found that there are specific speeds where the flow switch will activate (around 1700 rpm), but that going just below this (1600 rpm) will cause the flow switch to turn off. In addition, as the flow rate decreases as junk builds up in my DE filter, the flow switch will no longer work at the low rate of 1700 rpm. Of course, this is handy because it tells me I need to backwash the filter. But, it's also a little dangerous because it could mean that my pool is no longer being chlorinated. So, I set the low pool rate (e.g. under standard POOL mode) to 1850 just in case.

Our pool pad plumbing is rather tight, and like you, our IC60 is plumbed right after a 90 elbow. At some point, I will likely have to redo the plumbing to provide better flow to the IC60. As described in the Intellichlor manual, a straight section of pipe of 13" or greater is best for optimal flow detection. I guess that running through that 90 elbow is causing enough flow disruption that it requires higher total flow rates (and thus higher rpm) than if there was a straight section going into the IC60. As for why it shuts down after a while of running properly, I can only guess that the initial startup gives enough flow to activate the flow switch, and that the switch ultimately overcomes the water flow to turn off. Since the IC60 produces a greater level of chlorine than the IC40, I wonder if Pentair actually sets the flow switch to detect a stronger flow rate (e.g. so as to not allow buildup of H2 gas or chloride ions)?

 

[npkr01]

According to Pentair's literature, both the IC40 and IC 60 require the same flow rate, 25 gal/min, to activate the chlorinator. It still doesn't make sense to me that the IC60 will make chlorine on low pump speed with a green flow light for up to 49 minutes (always more than 8 minutes) before going red. If flow isn't adequate and the flow switch isn't making contact, one would think it should shut off immediately upon startup or never turn green in the first place.

My PB is having the Pentair rep look into it. Hopefully a replacement will solve the problem. If not, it looks like my pb will need to add a 12 to 18 inch straight section of pvc leading into the IC60. With a two-speed pump, it defeats the purpose to only be able to have the chlorinator make chlorine if high speed is running- I really need it to work on low speed.

 

[Pool Clown]

Your PB should re-plumb before the rep gets there. The rep could very well say, "it needs straight pipe before and after the cell" and walk away, and you will have just wasted a visit from the manufacturer. Every thing should be done to bring the systems' plumbing to what Pentair requires for the cell BEFORE the Rep gets there.
That would include having the correct salt level in the pool (even-though seemingly unrelated).

"Note: For best flow sensing, provide at least 12-18 inches of straight pipe in front of the cell"
Taken from the Intellichlor install and user manual.

I would also add that you should (if possible) do that behind the cell too.

 

[npkr01]

Problem appears to be solved.

My PB added 12 inches of straight pvc in front of (leading into) the IC60 2 days ago and I have had a continuous green flow light on low pump speed since then. Keeping my fingers crossed but it appears that turbulent flow was the problem.

Thanks to all for their input.