Balboa BP7 4.0kW Spa Control Retrofit Kit with TP500 – G6405

The Balboa BP7 G6405 4.0kW Spa Control Retrofit Kit with TP500 is a modern replacement solution for many older Balboa hot tub and spa control systems. Built around Balboa's highly configurable BP7 platform, this kit combines a genuine Balboa BP7 control system, 4.0kW heater, and TP500 topside control in one retrofit package.

The BP7 platform is particularly useful when an older spa control, circuit board, or topside is obsolete or no longer practical to repair. Its multiple equipment configurations allow the system to be adapted to a wide range of hot tub layouts.

Balboa BP7 G6405 Features

• Manufacturer: Balboa Water Group
• Retrofit Kit Part Number: G6405
• Control Family: BP7
• BP7 Control: G4361 Series
• Heater: 4.0kW
• Topside Control: Balboa TP500
• Application: Hot tub and spa control replacement / retrofit
• Highly Configurable: Multiple equipment setups available
• Genuine Balboa Water Group Retrofit System

What's Included with the G6405?

The Balboa G6405 retrofit package includes the major components needed to convert a compatible older spa control to the BP7 platform.

• Balboa BP7 4.0kW control system
• Balboa TP500 topside control panel
• TP500 panel overlay
• Topside bezel / adapter component
• 8-foot spa light wire assembly

Modern Replacement for Older Balboa Spa Controls

Balboa developed the BP7 platform with aftermarket replacement applications in mind. Depending on the original spa equipment and configuration, BP7 can provide a modern replacement path for many older Balboa control systems.

Potential retrofit applications include many controls from the:

• Balboa VS Series
• Balboa GS Series
• Balboa EL Series
• Balboa ML Series
• Other compatible Balboa and non-Balboa spa control applications

Important: BP7 compatibility depends on the electrical and equipment configuration of the spa. Always verify the existing control number, pumps, circulation system, blower, ozone, lighting and other connected equipment before selecting a replacement system.

Known Replacement Application: VS510SZ 54371HC2

The Balboa G6405 is used as a modern BP7 retrofit solution for certain Balboa VS510SZ systems including part number 54371HC2.

Because VS-series controls were produced in multiple configurations, the original control-box part number and connected equipment should still be verified before ordering.

Highly Configurable BP7 Platform

The BP7 platform provides numerous setup configurations, allowing one control platform to support many different spa equipment combinations. Depending on the selected setup, BP7 can accommodate combinations involving:

• Pump 1
• Pump 2
• Additional pump configurations
• Circulation pump
• Blower or auxiliary equipment
• Ozone system
• Spa lighting
• Compatible Balboa accessories

The proper BP7 setup must be selected during installation to match the equipment installed in the hot tub.

4.0kW Heater

The G6405 uses Balboa's 4.0kW BP7 heater configuration. This distinguishes it from the G6505 version, which uses a 5.5kW heater.

The original spa's electrical requirements and heater configuration should be verified before choosing between the 4.0kW and 5.5kW BP7 retrofit systems.

Includes Balboa TP500 Topside Control

The G6405 includes a Balboa TP500 topside control, allowing the control system and user interface to be upgraded together.

This is particularly useful when converting from an older Balboa control platform whose original topside panel is obsolete or incompatible with the newer BP7 system.

G6405 vs. G6505

Both retrofit kits use the Balboa BP7 platform and include a TP500 topside. The primary difference is the heater rating:

• G6405: BP7 + TP500 + 4.0kW heater
• G6505: BP7 + TP500 + 5.5kW heater

Do not select a higher heater rating simply because it provides more heating power. The spa's electrical system and original configuration must support the selected heater.

Why Upgrade to a Balboa BP7?

• Modern replacement option for many discontinued spa controls
• Genuine Balboa Water Group control system
• Multiple configurable equipment setups
• Supports multi-pump spa applications
• Modern Balboa TP-series interface
• Excellent retrofit platform for older hot tubs
• Widely supported Balboa replacement platform

Installation Information

The BP7 is a configurable spa control system and is not a plug-and-play replacement for every hot tub. The correct setup, voltage configuration, equipment outputs and wiring must be selected for the specific spa.

Installation should be performed by a qualified spa service technician or electrician familiar with hot tub control systems. Always follow Balboa installation instructions and applicable electrical codes.

Frequently Asked Questions

What is the difference between Balboa G6405 and G6505?

Both are BP7 retrofit kits with a TP500 topside. The G6405 uses a 4.0kW heater, while the G6505 uses a 5.5kW heater.

Does the G6405 include the TP500?

Yes. The G6405 retrofit kit includes the Balboa TP500 topside control along with the BP7 4.0kW control system and associated retrofit components.

Will G6405 replace my old VS510SZ?

G6405 is used as a BP7 retrofit replacement for certain VS510SZ systems, including known applications involving part number 54371HC2. Because VS510SZ systems were available in different configurations, verify the original part number and connected equipment before ordering.

Can BP7 operate more than one pump?

Yes. The BP7 platform supports numerous equipment configurations, including multi-pump spa applications. The available outputs depend on the setup selected for the particular spa.

How do I know whether I need the 4.0kW or 5.5kW version?

Check the specifications of the existing spa control and heater along with the spa's electrical configuration. If you are unsure, send Whirly Bros photos of the existing control-box label and equipment before ordering.

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Need help identifying your Balboa spa control?
Contact Whirly Bros with photos of your existing control-box label and topside keypad. We'll help identify the system and determine the appropriate modern replacement.