UPDATE: So, that manual override does work. First you turn the dial to "run" then you press the manual watering button (the one with the picture of a running faucet), THEN you choose the length of time to use it THEN you choose which side,left or right, by pushing the selector button (L/R). Wait a couple of seconds and you are in business! So glad that worked out because I've always really like this timer (purchased two years ago.). I had asked for an exchange and now I've decided to keep the extra one to replace another old one that the screen is impossible to read now. I've been wondering if there's something that could be put on the screen to protect it from the sun exposure that seems to ruin it over time?Original review. I haven't used the timer portion yet, but have been unable to activate the manual operation of the timer. I've had two of these timers previously and had no problems with any operation and was very pleased. I purchased this one to replace one from years ago that broke. The only complaint I've ever had with these is that the screen deteriorates over time and you can't view the selections at that point.I've ordered a replacement and I will update this review then.