

Openers · Kawartha Lakes
Photo-Eye Sensor Alignment or Replacement in Kawartha Lakes
Someone backed the car in a little too far, a bin or a bicycle brushed the track, and since then the door starts to close and comes back up.
In plain words
By the end of the visit you have a door that closes from every control and reverses the instant the beam is broken, a sensor pair mounted level at the right height with steady indicator lights, wiring that is secured and out of harm's way, and a written note of what was found and what was changed. The technician walks you through the two tests you can repeat monthly, points out which light is which, and leaves the opener's diagnostic chart where you can find it. It is a small job that puts a large piece of your door's protection back in service.
How the visit goesYou press the remote, the door drops a few centimetres, then climbs straight back to the top while the opener light blinks. Nothing is under the door. It has done this every evening this week.
Photo-Eye Sensor Alignment or Replacement
How the visit goes


Making sure it is the sensors and not the door
A door that reverses on the way down has two possible reasons, and only one of them lives at the floor. If the door touches something, including a bottom seal frozen to the slab, a travel limit set slightly long or a stiff door in cold weather, the force setting sends it back up. That looks like a sensor fault from the driveway but calls for a different fix. The technician checks whether the door reverses before it moves or after it meets resistance, watches the sensor lights during the cycle, and tries the door with the beam deliberately shaded. The answer decides whether the work stays with the sensors or moves to the settings.
Dealing with the sun
A receiver that looks into the low sun is fixed by geometry. The simplest cure is to swap the two sensors side to side so the receiver looks away from the doorway light and the sending eye, which is not affected, takes the sunny position. Where the layout rules that out, a small hood or shade is fitted over the receiving lens, deep enough to shield it without narrowing the beam path. The wiring is extended or re-routed as needed and both lights are checked at the time of day the fault used to appear, or with a strong light aimed at the lens to stand in for the sun.
Winter habits
In the cold months the sensors ask for a little attention. On frosty mornings give a misted lens a moment to clear rather than pressing close over and over, and wipe it with a dry cloth if it does not. Keep salt slush from building up against the brackets, since salt is what corrodes the mounts and terminals over time. Clear snow from just inside the door before closing it, and if the bottom seal has frozen to the slab, free it by hand rather than asking the opener to pull it loose. If the door closes at noon but not at nine, mention it; the low sun may be reaching the receiving eye and a shade sorts that out.
Photo-Eye Sensor Alignment or Replacement
In the van
Track-mount sensor brackets
Concrete anchors
Two-conductor low-voltage wire
Receiving-eye sun shade
Wall or floor angle brackets

Photo-Eye Sensor Alignment or Replacement
What affects the quote
Wall or floor mounting with anchors
Mounting into concrete or masonry rather than onto the track means drilling, anchors and sealing against water, which takes more time than clipping to the rail.
Force and travel adjustment alongside
If the reversing turns out to involve a travel limit set long or a force setting made in summer, adjusting and re-testing those settings is included as a small extra step.
Door-side findings
A balance problem, a stiff roller or a bottom seal that needs replacing sometimes shows up during testing. Those belong to their own service and are noted and quoted separately rather than hidden in the sensor work.
What to have ready
- Does the opener light flash when you press close, and how many times?
- Is there frost, snow, slush or salt around the sensors in winter?
- How many doors and openers are there?
Photo-Eye Sensor Alignment or Replacement: questions
QuestionsMy opener has no sensors at all. Can they be added?
If the opener predates the entrapment-protection standard, which operators have had to meet since the mid-1990s, its board has no sensor circuit and a pair cannot simply be wired in. The positive news is that a modern operator brings the whole package: matched sensors, force reversal and a monitored circuit. The technician confirms the model first, because some units do have the terminals and simply had their sensors removed.
Can any sensor pair be used with my opener?
Not any, no. Sensors are matched to the opener's make and generation, and a board from one era may ignore sensors from another even when the wires fit. The technician reads the model from the head unit label and fits the pair listed for it. Some operators accept a documented universal pair, and those are used where the maker lists them as suitable; on a very old unit with no compatible pair, a modern operator is the way forward.
What happens during the visit, in order?
Questions first: what the door does, when it began, what changed. Then the beam path is cleared, the sensor lights are read, the opener's flash code is counted, and the brackets and heights are measured. If the signs point to the circuit, the wire is traced and tested with a meter. The cause is fixed, whether that is alignment, brackets, wire, a shade or a new pair, and the visit closes with the beam test and the contact reversal test.
