🔌 Balboa GL2000 Mach 3 PCB – Spa Control Circuit Board

Replacement circuit board for GL2000 Mach 3 plastic control boxes – restore precise management to your spa system.

📋 Product Overview

The Balboa GL2000 Mach 3 PCB is a replacement circuit board for the GL2000 Mach 3 control box, designed for precise management of spa systems. It supports various pump configurations, a heater, ozone, and light, and is compatible with ML range topside controls such as the ML400, ML700, and ML900.

This PCB must only be used with a GL2000 Mach 3 plastic control box and should be installed by a competent individual or tradesman to avoid damage and warranty invalidation.

⚠️ IMPORTANT: This PCB is for PLASTIC control boxes only.

✨ Key Features

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

✅ Flexible Pump Control – Supports single or dual-speed Pump 1 with optional circulation pump

✅ Secondary Pump Support – Pump 2 single or dual-speed (if no blower used)

✅ Blower Option – Pump 3 or Air Blower available (if Pump 2 is single-speed)

✅ Expandable – Extra port available with an expander board

✅ Built-in Heater Control – Integrated heater management

✅ Ozone Ready – Ozone generator output included

✅ Dual Lighting Options – Supports 12V or 230V spa lighting

✅ M7 Sensor System – Dual M7 sensor inputs (x2)

✅ No Pressure Switch Required – Simplified installation

✅ ML Panel Compatible – Works with ML400, ML700, and ML900 topside controls

🔧 Technical Specifications

Specification	Value
Brand	Balboa
Model / Series	GL
Product Type	PCB
Input Voltage	230V
Frequency	50Hz
Pump 1	Single or dual-speed + circulation pump (optional)
Pump 2	Single or dual-speed (if no blower used)
Pump 3 / Air Blower	1 unit (if Pump 2 is single-speed)
Extra Port	Available with expander board
Heater Output	Yes
Ozone Output	Yes
Light Output	12V or 230V
Sensors	M7 x 2
Pressure Switch	No
Length	290 mm
Width	150 mm
Height	155 mm

🔗 Compatibility Guide

Compatible Control Boxes

Control Box	Compatibility
GL2000 Mach 3 (Plastic)	✅ Compatible
GL2001 Mach 3 (Plastic)	✅ Compatible

⚠️ NOT compatible with metal GL control boxes.

Compatible Topside Panels

Panel	Compatibility
ML400	✅ Compatible
ML700	✅ Compatible
ML900	✅ Compatible

Compatible Hot Tubs

Spa	Reference
Hydrospa Essence	PCB SN HSEX2000 54234

⚙️ Board Functions & Controls

Pump Control

Output	Function	Configuration
Pump 1	Main jet pump	Single or dual-speed
Circulation Pump	24hr circulation	Optional (with Pump 1)
Pump 2	Secondary jets	Single or dual-speed (if no blower)
Pump 3 / Blower	Third pump or air blower	1 unit (if P2 is single-speed)

Additional Outputs

Function	Specification
Heater	Yes
Ozone	Yes
Light	12V or 230V

Sensor System

Feature	Specification
Sensor Type	M7
Quantity	2
Pressure Switch	Not required

🛠️ Installation Requirements

⚠️ IMPORTANT: Installation should be carried out by a competent individual or tradesman to avoid damage and warranty invalidation.

Pre-Installation Checklist

• [ ] Verify this is a PLASTIC GL2000/GL2001 Mach 3 control box
• [ ] Disconnect all power at the isolator/breaker
• [ ] Photograph existing wiring connections
• [ ] Note existing DIP switch settings
• [ ] 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

⚠️ Safety Warnings

Electrical Safety

• ⚠️ ALWAYS disconnect power before any work
• ⚠️ Installation by competent tradesman recommended
• ⚠️ 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 PCB is for PLASTIC control boxes only
• ⚠️ Do NOT install in metal GL control boxes
• ⚠️ Incorrect installation may void warranty
• ⚠️ Damage caused by improper installation is not covered

🎯 Ideal Applications

Application	Suitability	Notes
♨️ GL2000 Mach 3 (Plastic)	✅ Direct replacement	Plastic box only
♨️ GL2001 Mach 3 (Plastic)	✅ Compatible	Plastic box only
♨️ Hydrospa Essence	✅ Compatible	PCB SN HSEX2000 54234

This board is designed for:

• Replacing faulty GL2000/GL2001 Mach 3 circuit boards
• Restoring full spa functionality
• Systems using ML400, ML700, or ML900 topside panels

❓ Frequently Asked Questions

Q: How do I know if this board fits my spa? A: This board fits GL2000/GL2001 Mach 3 PLASTIC control boxes only. It is NOT compatible with metal GL boxes.

Q: What topside panels work with this board? A: Compatible with ML range topside controls including ML400, ML700, and ML900.

Q: Do I need a qualified electrician to install this? A: Installation should be carried out by a competent individual or tradesman to avoid damage and warranty invalidation.

Q: Can I use both Pump 2 and a blower? A: No. Pump 2 can be single or dual-speed if no blower is used. Pump 3 or Air Blower is available only if Pump 2 is single-speed.

Q: What sensors does this board use? A: The board uses M7 sensors (x2) and does not require a pressure switch.

Q: What lighting options are available? A: The board supports both 12V and 230V spa lighting.

Q: Can I add more outputs? A: Yes. An extra port is available with the addition of an expander board.

🏆 Why Choose the Balboa GL2000 Mach 3 PCB

• ✅ Balboa Quality – Trusted brand in spa control systems
• ✅ 230V 50Hz – Designed for UK electrical systems
• ✅ Flexible Pump Control – Supports multiple pump configurations
• ✅ M7 Sensor System – No pressure switch required
• ✅ ML Panel Compatible – Works with ML400, ML700, ML900
• ✅ Expandable – Extra port available with expander board

🤝 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
• ✅ Compatible parts and accessories available
• ✅ Help with identifying correct replacement board

✨ Summary

The Balboa GL2000 Mach 3 PCB is a replacement circuit board for GL2000/GL2001 Mach 3 plastic control boxes. Operating at 230V 50Hz, this board supports flexible pump configurations including single or dual-speed Pump 1 with optional circulation pump, Pump 2, and Pump 3 or blower options. Features include built-in heater control, ozone output, 12V or 230V lighting support, and dual M7 sensors eliminating the need for a pressure switch. Compatible with ML400, ML700, and ML900 topside panels, with expansion capability via expander board. Dimensions: 290mm × 150mm × 155mm. Installation by a competent tradesman is required. This PCB fits PLASTIC GL2000/GL2001 Mach 3 control boxes only.

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.