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Garage Door Technician
Garage Door Maintenance & Service Certification
Battery Backup, Remotes & Customer Education
Knowledge Check
Battery Backup, Remotes & Customer Education
Knowledge Check
Knowledge Check
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Why should homeowners be instructed on how to clean garage door photo eye lenses?
A
Lens cleaning is only required on commercial installations
B
Dirty or cobweb-covered photo eye lenses cause the door to refuse to close, and owners who know to clean them can resolve this common issue without a service call
C
Homeowners should not touch photo eyes as they are calibrated factory components
D
Dirty lenses cause alignment drift that requires technician recalibration
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