Aqualink erratic pump relay cycling

[lakeboater]

I want to add my name to those who had success solving rapid pump relay cycling when the Aqualink goes into Freeze protection mode. The fix to this apparent software bug is to add a "device" to freeze protection in the controller menu. In my case, I had a spare Aux channel that has no function. Now when freeze protection mode initiates, the pump runs for a minimum period of time....like 15 or 30 minutes, even if the temperature increases.

I learned about this fix on TFP from an old post. Another poster, who did not have a spare channel, added the spa blower and turned off the blower motor breaker in cool weather.

You can also lower the freeze protection initiation temperature to 34 F in the freeze protection menu selection.

Actually, I experienced this issue first at temperatures well above the 38 F freeze protection temp. I heard the pump randomly turn on momentarily. When it got much worse, I was fortunate enough to look at the controller screen where it reported going into freeze protection mode. But that message disappears quickly when a second device is not assigned, so I was fortunate. Even though the air temperature appeared correct, it must have had some droops. I ordered another sensor but then used contact cleaner on the wires and screw connection of the existing one. This cleaning operation resolved the random pump starts, but the issue still remained near the freeze protection threshold, until another device was assigned.

 

[Jimrahbe]

lb,

Thanks for the feedback... It is posts like yours that make TFP a great troubleshooting resource..

Thanks again,

Jim R.

 

[lakeboater]

Unfortunately the problem is not solved. The freeze protect works fine when I reduce the temperature with ice water. I even tried hovering around the set point and it still works correctly (turns on pump for a significant amount of time even if air temp rises). But in actual operation, the rapid pump relay action occurs.

The odd thing is that the air temp seems to read too low when this occurs. The locally reported low is about 50 F, yet the air temp goes down below 40 F. It reads what I would expect during the day and it seems accurate in the ice water dunk test. I have a new sensor that I will try but it seems like a software problem, as others have reported. I previously cleaned the wires and connection.

 

[lakeboater]

Update: I power cycled the unit, cleared memory and reprogrammed devices, time and temperature settings. I assigned an unused device to freeze protection. I also found one broken wire from the all button controller. It may have occurred when I removed the board to get to the battery, but the cables had plenty of slack and only 1 of 4 wires broke???It must have been cracked. I have had two nights where freeze protection was activated and I don't believe I had any erratic cycling. I'm not sure what fixed the problem. It seems that if the broken wire were a problem, there would have been other issues, plus this erratic cycling is a known issue.

I also found that I have a quite recent software. Rev T.2

The Aqualink manual does discuss "phantom programs" and suggests power cycle and clear memory, so that is my best guess as to what was going on.