Pentair AquaLumin III Nichless Light Vinyl Mounting Bracket Assembly, 3/4" | 78887700

Pentair AquaLumin III Vinyl Liner Mounting Bracket, 3/4" Hub | 78887700

The Pentair 78887700 is a vinyl liner mounting bracket for the Pentair AquaLumin III nicheless pool and spa light. It provides the proper mounting interface through a vinyl liner wall and includes a 3/4" hub connection point for the light’s conduit/cord routing.

Key Features

• Designed for vinyl liner pools/spas using Pentair AquaLumin III nicheless lights.
• 3/4" hub connection for conduit/installation routing.
• New-installation hardware component (commonly specified when installing or converting an AquaLumin III light in a vinyl application).
• OEM Pentair replacement part for correct fit and alignment.

Compatibility

• Fits: Pentair AquaLumin III nicheless pool & spa lights (vinyl liner installations)
• Tip: If you are replacing an existing bracket, confirm the hub size and the light model to match your current setup.

Specifications

• Brand: Pentair
• Part Number: 78887700
• Part Type: Vinyl liner mounting bracket
• Hub Size: 3/4"
• Catalog Reference (common): 3626-25
• Quantity: Sold individually

Common Reasons to Replace

• Bracket is cracked, warped, or damaged from impact or freeze conditions
• Conduit/hub area is stripped or no longer seals properly
• Light is being reinstalled during a liner replacement and the bracket is worn or corroded
• Converting/adding an AquaLumin III light to a vinyl liner wall application

Installation Notes

• Follow the AquaLumin III installation instructions for correct placement, sealing surfaces, and liner cutout alignment.
• Confirm the hub/conduit routing is properly supported and watertight per code and manufacturer guidance.
• Use care when tightening fasteners on vinyl applications to avoid distorting the liner or bracket mating surfaces.
• Underwater lighting work should be performed by a qualified pool professional/electrician as required by local code.

Related Products

• Search Aqua Pool Supply for 78887700
• Pentair AquaLumin III lights & parts
• Pool light gaskets
• Light conduit & electrical fittings

Maintenance Tips

• When servicing underwater lights, inspect sealing surfaces and replace worn gaskets to reduce the risk of moisture intrusion.
• Keep chemical levels balanced—highly aggressive water can accelerate corrosion and degrade plastic components over time.
• If you see recurring moisture/fogging or leaking around the light area, stop use and inspect the mounting/sealing stack immediately.