I realize this is a 2 yr old thread, but I recently encountered a similar problem and thought I'd update this thread for the benefit of future people that come across it while searching for a solution as I was. I was able to find and fix my problem.
Although I opened our pool a couple of months ago, I hadn't checked out the Glacier Cooler components until now, as it's just now getting warm enough to start needing it. A Intermatic pe24va actuator would not open the cooler valve. I had not made any changes since it was last used and working last season. In the first "poking around" I got it to run a little... I manually opened the valve part way and then the motor opened it the rest of the way. I was then able to close the valve with the controller. But after that it was "stuck" again. Motor ran smooth and quiet when it did run, so I didn't think it was the motor.
I started by checking voltage at the cable wire ends where they enter the actuator. There are 3 wires, red, black, and white. You should have 24vac across either the red and white or the black and white, but not both at the same time. Voltage across one color (red or black) will occur when the controller turns the valve on while while voltage across the other color will occur when the controller turns the valve off, so you need to do 2 checks. In my case, I had 24vac at the cable end. If I didn't, I would have checked the other end of the cable where it connects to the controller. If you have 24vac there, the problem is a broken wire in the cable. If you don't have 24vac there, the problem is in the controller, not the valve.
Once I saw I was getting 24vac to the cable ends in the actuator, it was simply a matter of tracing the wires and checking voltage at each connection point until you find where you are losing power. It might be something simple such as a bad wire nut connection. In my case, I found the problem to be a solder connection on one of the toggle switch terminals to the little pc board the toggle switch attaches to. I had power to the point the white wire was soldered to the pcb. I could trace the foil on the pcb to know which toggle switch terminal(s) was the next check point. The pcb foil jumped the white wire to two of the six toggle switch terminals. I had voltage at one of the toggle terminals, but not the other (remember to check with the switch in all positions), so I knew either the solder joint was bad or there was a break in the foil on the pcb. I was able to resolder the switch terminal to the board and that corrected the problem. If that hadn't fixed it, I would've soldered a jumper wire across those two terminals to take the place of the damaged pcb foil that was suppose to serve as the jumper. We had a much colder winter than usual, so I'm guessing the contraction/expansion from the extreme temp changes caused the solder connection to crack.
One really needs a multi tester to trouble shoot these things, but there are a few things you can do if you don't have a tester to find the problem or at least narrow it down. You can check the micro switches by shorting across their terminals with a jumper wire or a screwdriver. If that makes the motor run, you have a bad micro switch. You can temporarily jumper the incoming cable wires directly to the motor wires. If the motor runs smoothly, then your problem is a connection problem within the actuator (bad toggle switch, bad micro switch, bad solder joint, bad wire nut connection, or broken wire).
Another thing I have always done as a matter of preventative maintenance is to make sure the actuators are wired such that they work correctly with the toggle switch in the down position. I'm not sure how much difference this makes, if any, but my thoughts in doing so is that rain hitting the switch lever will run away from the actuator and drip off the end of the lever instead of running down the lever towards the actuator and possibly getting inside the switch. It may not help, but it doesn't cost anything to do and can't hurt.