The G8474 is a Balboa part number for the TP740T topside control panel.
This generic, 9-button panel is used by numerous hot tub manufacturers who incorporate Balboa control systems into their spas.
Manufacturers That Have Used the Balboa G8474 Topside
Since Balboa is the largest spa parts manufacturer globally, its components are widely used across many brands. Manufacturers known to use Balboa systems compatible with this panel include:
Artesian Spas: The G8474 is cross-referenced with their part number OP33-1906-08.
Viking Spas: This panel replaces their part number 91001 Trapezoid model.
Cal Spas
Coast Spas
Coleman Spas
Dynasty Spas
Jacuzzi (on certain models)
Master Spas
Sundance Spas (on certain models)
Key Features of the G8474
The panel (Model TP740T) has the following specifications:
Manufacturer: Balboa Water Group
Buttons: 9-button configuration (requires a separate overlay, like part #17632)
Connection: 4-pin Molex style plug
Compatibility: Designed for use with Balboa BP series control systems (e.g., BP501, BP2000, BP2100).
To ensure you receive the exact replacement overlay for your specific model's functions (e.g., Jets 1, Jets 2, Blower, Light, etc.), it is best to check the manufacturer's part number on your existing topside panel or spa's control box.
To confirm if your spa is compatible with the Balboa G8474 (TP740T) topside, you must locate specific identifying numbers on your existing equipment. These numbers ensure the software (chip) and hardware (spa pack) will communicate correctly with the new panel.
1. Locate the Spa Pack Part Number
The "spa pack" is the main metal or plastic control box located inside the equipment compartment.
Safety First: Turn off the power at the main breaker before opening the hot tub cabinet.
The Sticker: Look for a white or silver label on the outside of the control box.
The Number: You are looking for a 5-digit Balboa part number that typically starts with 5 (e.g., 54xxx, 56xxx).
Compatibility: The G8474 is part of the BP Series and is designed for modern Balboa BP spa packs (like the BP7, BP501, or BP2000).
2. Check the Circuit Board Chip Number
If the sticker on the box is missing or unreadable, you must look at the circuit board itself.
The Chip: Locate a small white sticker on one of the main logic chips on the board.
The Code: This number (e.g., BP501R1A) identifies the exact software version. TheG8474 requires a BP-series software version to function; it will not work with older VS or GS series boards, even if the plug looks similar.
3. Verify the Topside Part Number
If you are trying to replace your existing panel, find the original part number on the panel itself:
Back of Panel: You may need to pry the panel up from the spa shell (it is usually held by adhesive) to see the sticker on the underside.
The Sticker: Look for a white bar-coded sticker. The Balboa part number will often start with 5.
Identifying Your Spa Brand
If you cannot find these numbers, locating the spa's serial number can help a dealer look up the original parts.
Check the lower corners of the exterior cabinet for a metal plate.
Look for a sticker on the floor or wall inside the equipment compartment.
For a visual walkthrough on identifying your Balboa spa pack and ensuring topside compatibility:
