Timer stops when it hits off tripper


Active member
Aug 5, 2018
Whitehouse Station, NJ
I haven't been able to get the timer to work properly ever since it was installed about 2 years ago when we got our 21ft round above ground pool. I just ran the pump manually. This year, I'm sick of having this be no more than a switch, so I want to get it working.

After the timer hits the off tripper, the timer stops running.
If I pull out the dial, and set it to 12 noon, trip the switch at the bottom to on and then let the pump run, the pump goes off at 6pm (as it should) but the dial stops moving. It moves fine if I flip the switch back on, so it seems to me like the switch shuts power off to the timer in addition to the outlet it controls. Could the installers have mis-wired it? If so, how? I'm comfortable working with electricity (installing lights, outlets, etc, but I've never worked with a timer like this.

pool timer.jpg
Timer stops just after happy hour. I know how that feels :)


In The Industry
Jul 20, 2017
Windsor, Ontario. Canada
The wiring diagram is right there on the front cover. I have used this exact unit many times. At first read i thought the motor wasn't strong enough to trip the off but on a re read i understand ya now. Yes it is wired wrong.


Well-known member
Jul 12, 2012
Richmond, Va.
Yes, breaker off then try that.
Just to note. These are still the best brand. But common to have to replace. I have had them last 1 year and in other cases 10 years with no problems. I always keep a spare in stock for my pool. Not a question of if, but when you will need it.

Also if replace you dont have to replace the gray metal box. Just get the same one. Disconnect wires inside the box and the whole unit unclips from the box. So very easy and quick. Often can be cheaper to buy the whole unit than just the timer assembly. And use what you need.
Still a good chance you may have got a bad one. But easy to find out at least.


TFP Expert
Mar 2, 2011
If they have the line and load wires reversed, I should switch the two black wires, right?
View attachment 142462

The two small white wires go to the clock.

The black wire on the right is powered and it connects to the left terminal when the switch is in the On position.

That's why the timer only works with the switch in the On position.

Move the incoming power (line) to the left and the clock will always have power.

Move the load wire to the right.