You do not lubricate a photo eye. There is nothing inside it that moves. It is an infrared sender on one side of the opening and a receiver on the other, and the only maintenance they want is to be kept clean, aligned and dry.
Putting lubricant anywhere near a sensor head makes things worse. Oil film on the lens scatters the beam, and it holds onto dust. A sensor that was working intermittently will stop working altogether.
What photo eyes actually need
- Clean lenses. Dry cloth. No solvents, no oil, no silicone spray. In a cold store or a wash bay, condensation on the lens is a regular cause of nuisance reversals.
- Alignment. Both heads at the same height, square to each other. Check the LEDs; most units show a steady light on the receiver when the beam is good.
- Tight brackets. Vibration works the fasteners loose and the head drifts out of line.
- Sound wiring. Rodent damage and conduit wear are common. A chewed sensor wire on a monitored operator will stop the door closing on momentary contact entirely, which is the system working as designed.
- Protection from impact. If pallets or forklifts keep catching the heads, they want guarding.
Where the confusion comes from
A door service includes lubrication, so people assume everything gets lubricated. It does not. The parts that want lubricant are the spring coils, roller bearings, hinges, end and centre bearings, and the drive chain. The electronics want to be left dry: photo eyes, limit switches, the control board, the wall button and the receiver.
Tracks are the other one people get wrong. Tracks get wiped clean, not greased.
If cleaning does not fix it
If both lenses are clean, the heads are square and the LEDs still will not settle, the fault is in the wiring or the head itself. Trace the circuit back to the board before replacing anything. Photo eyes do fail, particularly in wet and cold environments, but a lot of sensor complaints turn out to be a damaged wire or a failing control board.
If your door will not close and the eyes look fine, call (604) 206-5727. We will test the circuit properly and tell you what it actually is.
