🛠️ Balboa Expander Board Pump Relay (GS-GL) – 1-Speed Pump or Blower Expansion Module

Compact relay expansion board to add one 1-speed pump or blower to your Balboa GS and GL control systems.

📋 Product Overview

This PCB is used in many Balboa GS and GL Systems to add a 1-speed pump or blower. The Balboa Expander Board Pump Relay is designed to extend the capabilities of GS and GL series control boxes, allowing you to add one additional 1-speed pump or blower to your spa system.

This compact expansion module connects to your existing GS or GL main board and provides the additional relay circuitry needed to operate an extra 1-speed pump or blower output.

✨ Key Features

✅ 230V / 50Hz Operation – Designed for UK and European electrical systems

✅ Flexible Output – Controls one additional 1-speed pump OR blower

✅ Ultra-Compact Design – Smallest footprint at just 80mm × 41mm

✅ GS and GL Compatible – Works with many Balboa GS and GL control boxes

✅ Official Balboa Part – Part number 53547

✅ Dual Function – Can be used for pump or blower expansion

🔧 Technical Specifications

Specification	Value
Brand	Balboa
Balboa Part Number	53547
Model / Series	GS and GL
Product Type	Expander Board
Input Voltage	230V
Frequency	50Hz
Output Support	One additional 1-speed pump or blower
Length	80 mm
Height	41 mm

✅ Compatibility Guide

Compatible Control Systems

Control System	Compatibility
Balboa GS series control boxes	✅ Compatible (some models)
Balboa GL series control boxes	✅ Compatible (some models)

Note: This board is compatible with some Balboa GS and GL control boxes. Please verify your specific system before ordering.

Alternative for Higher Current

Requirement	Recommended Board
Standard pump/blower	This board (CB-EX535)
30A fuse protection needed	CB-EX550

If you need 30A fuse protection for your pump, please use CB-EX550 instead of this board.

⚙️ Board Functions

Output Options

Function	Specification
Output Type	1-speed pump OR blower
Number of Outputs	1

This expander gives you flexibility – you can use it to add either:

• One additional 1-speed pump, OR
• One additional blower

How It Works

The expander board connects to your GS or GL main control board and provides:

• Additional relay control for a 1-speed output
• Integration with existing topside panel controls
• Pump or blower switching capability

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🛠️ Installation Requirements

⚠️ IMPORTANT: This should be done by an experienced tradesman or a competent individual as a faulty install could result in board damage and invalidate warranty.

Pre-Installation Checklist

• [ ] Verify you have a compatible GS or GL control system
• [ ] Confirm your pump/blower is 1-speed
• [ ] Check if you need 30A protection (if yes, use CB-EX550 instead)
• [ ] Disconnect all power at the isolator/breaker
• [ ] Photograph existing wiring connections
• [ ] Allow capacitors to discharge (wait 5 minutes minimum)

Electrical Requirements

Requirement	Specification
Supply Voltage	230V
Frequency	50Hz
RCD Protection	Required (30mA recommended)
Earth Connection	Mandatory

💡 Tip: This board must be installed in conjunction with a compatible GS or GL main board – it cannot operate independently.

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⚠️ Safety Warnings

Electrical Safety

• ⚠️ ALWAYS disconnect power before any work
• ⚠️ Installation by experienced tradesman or competent individual required
• ⚠️ Ensure correct voltage supply (230V, 50Hz)
• ⚠️ Verify RCD protection is installed and functioning
• ⚠️ Never operate spa with covers removed from electrical components

Important Notes

• ⚠️ This is an expander board – not a main control PCB
• ⚠️ This PCB is for some Balboa GS and GL control boxes only
• ⚠️ Must not be fitted to any other device/product
• ⚠️ Faulty install could result in board damage
• ⚠️ Faulty install will invalidate warranty
• ⚠️ Use CB-EX550 if you require 30A fuse protection

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🎯 Ideal Applications

Application	Suitability	Notes
♨️ Balboa GS Series Systems	✅ Compatible	Check specific model
♨️ Balboa GL Series Systems	✅ Compatible	Check specific model
♨️ 1-Speed Pump Addition	✅ Ideal	Standard current pumps
♨️ Blower Addition	✅ Ideal	Standard blower expansion
♨️ Expander Replacement	✅ Direct replacement	Part number 53547

This board is designed for:

• Adding a 1-speed pump to GS or GL systems
• Adding a blower to GS or GL systems
• Replacing faulty expander boards (part 53547)
• Standard current applications (for 30A protection, use CB-EX550)

❓ Frequently Asked Questions

Q: Is this a main control board or an expander? A: This is an expander board that works alongside your GS or GL main control board. It adds the capability to control one additional 1-speed pump or blower.

Q: Can I add a 2-speed pump with this board? A: No, this board supports 1-speed pumps only. For 2-speed pump expansion, you would need a different expander.

Q: Can I use this for either a pump OR a blower? A: Yes, this board can be used to add either one 1-speed pump or one blower – you choose based on your spa requirements.

Q: What if I need 30A fuse protection? A: If you require 30A fuse protection for your pump, please use CB-EX550 instead of this board.

Q: Will this work with all GS and GL systems? A: It works with some Balboa GS and GL control boxes. Please verify your specific system compatibility before ordering.

Q: What is the Balboa part number? A: The official Balboa part number is 53547.

GS-GL Expander Options:

Requirement	Recommended Board
Standard 1-speed pump or blower	This board (CB-EX535 / 53547)
30A fuse protection needed	CB-EX550

🏆 Why Choose the Balboa GS-GL Pump Relay Expander Board

• ✅ Official Balboa Part – Part number 53547
• ✅ 230V / 50Hz – Designed for UK electrical systems
• ✅ Dual Function – Add pump OR blower with one board
• ✅ 1-Speed Output – Controls standard speed pumps/blowers
• ✅ Smallest Size – Just 80mm × 41mm footprint
• ✅ Wide Compatibility – Works with many GS and GL systems
• ✅ Proven Reliability – Balboa engineering quality

🤝 Why Buy From Parts4Tubs

• ✅ UK-based company with local support
• ✅ Fast UK delivery
• ✅ Expert technical advice from spa specialists
• ✅ Competitive pricing
• ✅ Full warranty support
• ✅ Easy returns within 30 days (unfitted items)
• ✅ Compatible parts and accessories available
• ✅ Help with identifying correct replacement board

✨ Summary

The Balboa Expander Board Pump Relay (GS-GL) is a compact expansion module designed for many Balboa GS and GL control systems. Operating at 230V / 50Hz, this board (Balboa part number 53547) adds the capability to control one additional 1-speed pump or blower. With dimensions of just 80mm × 41mm, it’s the smallest Balboa expander available. This versatile board can be used for either pump or blower expansion. If 30A fuse protection is required, use CB-EX550 instead. This is an expander board, not a main control PCB – it requires a GS or GL main board to function. Installation by an experienced tradesman or competent individual is required.

Finding and identifying a replacement Hot Tub Circuit Board (PCB)

If you are looking to replace a failed PCB on your Hot Tub’s spa pack, then quite often identifying the part that you need can be the hardest thing.

Firstly, you are looking for a model number on the actual circuit board itself. Having the model or serial of your hot tub is not going to help at this point, you need to find the number on the PCB itself.

Now, with certain brands of PCB, the number of the replacement PCB that you need is not going to match identically the one you are replacing. Why is that I hear you ask?

Well, normally, it is an updated version. This means that it might have updated firmware on the PCB or be a later revision. Normally, this means that the part number would be slightly different. This is usually indicated with a “12345678 -x” at the end of that part number where x indicated a firmware revision.

In some cases, there will be some following letters on the part number of the circuit board, “12345678 -x MAS” this can indicate that the PCB was used for an OEM meaning it was produced for a certain hot tub manufacturer and the letters identify the manufacturer.

This means if you source an original PCB, it will not have the letters, but will in most cases work just fine.

It can be confusing I know!

What if you can’t find a model number?

If you can’t find a model number on the PCB itself, then you need to look for a model number on the spa pack. Normally, there is a sticker on the outside of the spa pack that tells you the current ratings and input voltages etc and this will have a model number.

In general, most spa packs in the USA are manufactured by Balboa, Hydro-Quip, ACC or Gecko. I know I am generalising here, but if you have a spa pack that has the brand of your hot tub on, it will be an OEM so the key is identifying who made the original box.

From there, you can normally find an original PCB that you will be able to switch out.

For example, the Balboa VS (value series) is a very popular spa pack that has been used by multiple hot tub manufacturers under their own brand names. Whatever they have called it, strip it back and it is still a Balboa VS.

Visual Inspection

One of the most important things you can do when you are looking for a replacement is to visually inspect the PCB that you have versus the picture online of the replacement you are considering. They need to look the same even if there are the differences in firmware revisions or OEM part numbers, you should be visually replacing a PCB that looks like the one you have.

Configuring a replacement Hot Tub Circuit Board (PCB)

When you get a new PCB, you are more than likely going to need to configure it. Most PCBs have a number of different modes and setups that the can operate in. For this, you will need to manual or spec sheet to guide you.

For things like DIP switches, most of the time you can copy the settings from your original circuit board.

You may need to move jumpers or even wires to configure voltages – the key here is that you read the schematic and don’t expect the PCB to just work out of the box – it usually doesn’t.

Troubleshooting a Hot Tub Circuit Board (PCB)

Here are some common things you will see when you replace a PCB on a hot tub.

You press the buttons on the topside control and they don’t control the right parts (pumps or blower etc) – this is a mode configuration thing and you will either need to change some DIP switches on the PCB or an internal or low level programming mode on the topside control. Check the manual for how to do this.

To check this, unplug all of your kit – heater, pumps, blower and then turn on the PCB. If it trips with nothing plugged in, usually the voltage is incorrectly set and what is happening is that live current is being sent to the ground – because you have 4 wires into the PCB rather than 3. Current on the ground loop causes the trip. Check the settings to make sure it is configures for 230V.

It might not trip until you physically turn on a pump or a blower.