⚡ Master Spas® MS1600 Replacement Circuit Board — X801115 — Balboa® 55241 — VS501SZ

Genuine OEM replacement circuit board for Master Spas® MS1600 control systems — used in Twilight Series, Down East Spas®, H2X Swim Spas, Legend Series, and Michael Phelps Swim Spas — VS501SZ platform.

⚠️ IMPORTANT — PLEASE READ BEFORE ORDERING

• Chip number verification required. The chip for this board is MS1600R1A. Locate the chip sticker near the center of your existing board. Do not order by appearance alone.
• Board markings to expect. The physical PCB board will typically display “Balboa 22972_E VS500Z COPYRIGHT 2007” on the bottom right. You may also see Kit 44103 printed on the back. The chip sticker should read MS1600R1A.
• No documentation included. This board does not come with installation instructions or a wiring schematic. Obtain the wiring diagram from the back of your spa pack cover before installation.
• Daughter board kit (if applicable). If your system uses a daughter board (expander board for additional pump outputs), the compatible daughter board kit is X300026 (Balboa Equipment Daughter Board Kit for 40/510/1500/1600 systems). This is sold separately.
• DIP switch and voltage configuration required. Correct voltage setup, component wire positioning, and DIP switch settings must be applied. Refer to the wiring schematic on the back of the spa pack cover.

📋 Product Overview

The Master Spas® X801115 is the genuine OEM replacement circuit board for MS1600 control systems, manufactured by Balboa Water Group (Balboa part numbers 55241 / 55240). It uses the VS501SZ platform and is found in 2008–2010 Down East Spas models, 2009 and 2014–2017 Twilight Series models, various H2X Swim Spas, Legend Series LSX557, and Michael Phelps Swim Spas.

The control boxes compatible with this board carry numbers 55420, 55543-01, and MS1600H4. The physical PCB may show the marking “22972_E VS500Z COPYRIGHT 2007” — this is the underlying PCB designation and is normal. If a complete control pack replacement is needed instead of just the circuit board, the complete pack part number is X300786.

💡 Key Features

✅ Genuine OEM replacement circuit board — Balboa-manufactured for Master Spas®
✅ Master Spa Part Number: X801115 (also: MASX801115)
✅ Balboa Part Numbers: 55241 / 55240
✅ Control Box Numbers: 55420 / 55543-01 / MS1600H4
✅ Chip: MS1600R1A
✅ Platform: VS501SZ — Balboa Value Series
✅ Board dimensions: 11.0″ L × 5.0″ H (27.94 cm × 12.70 cm) | Weight: 2.1125 lbs. (955 g)
✅ Compatible with Twilight Series, Down East Spas®, H2X Swim Spas, Legend Series, Michael Phelps Swim Spas
✅ Complete pack replacement available: X300786
✅ Factory-new — never installed
✅ 1-year limited manufacturer’s warranty

🔧 Technical Specifications

Specification	Value
Master Spa Part Number	X801115 (also: MASX801115)
Balboa Part Numbers	55241 / 55240
Control Box Numbers	55420 / 55543-01 / MS1600H4
Chip Designation	MS1600R1A
Platform	VS501SZ — Balboa Value Series
PCB Board Markings	Balboa 22972_E VS500Z COPYRIGHT 2007 (bottom right)
Back of Board	May show Kit 44103
Board Dimensions	11.0″ L × 5.0″ H (27.94 cm × 12.70 cm)
Weight	2.1125 lbs. (955 g)
Documentation	Not included — obtain schematic from spa pack cover
Daughter Board Kit	X300026 (sold separately, if applicable)
Complete Pack Replacement	X300786 (sold separately)
Board Type	New — genuine OEM
Returns	Non-returnable (all electronics final sale)
Warranty	1-year limited manufacturer’s warranty

⚠️ For voltage, amperage, heater output, pump configuration, and breaker specifications, refer to the wiring diagram and rating label on the back of your spa pack cover.

🔗 Compatibility Guide

Compatible Spa Brands and Models:

Twilight Series Spas — 2009 and 2014–2017:

Model
TS 240
TS 6.2
TS 67.25
TS 7.2
TS 7.25
TS 8.2
TS 8.25
TS 8.3
TS 8.35
TS 87.3

Down East Spas® — 2009–2010:

Model
Windsor SE STS
Windsor 3 STS
East Hampton SE
Portsmouth SE
Portsmouth 3
Windsor SE
Windsor 3
Exeter SE
Exeter 3
Cape Cod SE
Cape Cod 3

H2X Swim Spas — 2008–2011 and 2015–2017:

Model
H2X Cross Trainer (2008–2011)
H2X Swim Spa (2008–2011)
Therapool SE (2015–2017)
Therapool Deep (2015–2017)
Trainer 15 (2015–2017)
Trainer 15 Deep (2015–2017)
Trainer 18 (2015–2017)
Trainer 19 (2015–2017)
Trainer 19 Deep (2015–2017)

Legend Series Spas — 2008–2012:

Model
LSX 557

Michael Phelps Swim Spas — 2012–2013 and 2016–2017:

Model
Momentum 80 (2012–2013)
Momentum 80 (2016–2017)
Momentum 80 Deep (2016–2017)

⚠️ Always verify the chip number (MS1600R1A) on your existing board before ordering, regardless of spa brand or year. Chip number is the definitive identifier.

⚠️ Confirm control box number is 55420, 55543-01, or MS1600H4 before ordering.

How to Confirm Compatibility:

1. Locate the chip sticker near the center of your existing board — confirm it reads MS1600R1A
2. Look for Balboa number 55241 printed on the board
3. Confirm control box number is 55420, 55543-01, or MS1600H4
4. If the PCB shows “22972_E VS500Z COPYRIGHT 2007” — this is correct and expected

Replaces These Part Numbers:

Part / Chip Number	Notes
X801115	Master Spa PN — this board
MASX801115	Alternate Master Spa PN format
55241	Balboa PN
55240	Balboa alt PN
MS1600R1A	Chip designation

🛠️ Installation Requirements

Pre-Installation Checklist:

• [ ] Confirm chip reads MS1600R1A on existing board
• [ ] Confirm Balboa number 55241 on existing board if visible
• [ ] Confirm control box is 55420, 55543-01, or MS1600H4
• [ ] Obtain wiring schematic from the back of the spa pack cover before starting — no documentation is included with this board
• [ ] If applicable: confirm whether a daughter board (X300026) is also needed
• [ ] Photograph all wiring connections and DIP switch positions before removal
• [ ] Disconnect all power at GFCI breaker or service disconnect
• [ ] Allow capacitors to discharge before handling board

Electrical Requirements:

Requirement	Specification
GFCI	Class A GFCI required — NEC Article 680
Ground & Bonding	Required — NEC Article 680
Dedicated Circuit	Required
Disconnect Box	Within line of sight of spa, at least 5 ft away
Voltage	Refer to spa pack wiring diagram and rating label
Wire Type	Copper conductors only

⚠️ Safety Warnings

• ⚠️ ALWAYS disconnect all power before circuit board work
• ⚠️ Licensed electrician installation required; NEC Article 680 compliance mandatory
• ⚠️ GFCI required; grounding and bonding required per NEC Article 680
• ⚠️ Do not order based on appearance — confirm chip reads MS1600R1A
• ⚠️ No instructions included — wiring schematic must be sourced from spa pack cover
• ⚠️ DIP switch and voltage configuration required — refer to wiring schematic
• ⚠️ Damage from incorrect installation is NOT covered under warranty

❓ Frequently Asked Questions

Q: My board shows “22972_E VS500Z COPYRIGHT 2007” — is this the right board? A: Yes. The physical PCB plate on this board displays “Balboa 22972_E VS500Z COPYRIGHT 2007” on the bottom right. This is the underlying PCB designation — it does not indicate a different product. The correct identifiers for ordering are X801115 (Master Spa PN), 55241 (Balboa PN), and MS1600R1A (chip sticker near center of board).

Q: Does this board include a wiring diagram or installation instructions? A: No. This board does not come with any documentation. The wiring schematic for your specific system is printed on a label affixed to the back of your spa pack cover. Obtain and review this schematic before installation.

Q: What is the X300026 daughter board kit? A: The X300026 is a Balboa Equipment Daughter Board Kit compatible with the 40/510/1500/1600 system family. If your spa uses an expander/daughter board alongside the main circuit board, and that board also needs replacement, the X300026 is the compatible kit. It is sold separately. Contact Parts4Tubs to confirm if your system requires this additional component.

Q: What if I need to replace the complete control pack rather than just the circuit board? A: The complete pack replacement for the MS1600 system is X300786. Contact Parts4Tubs for assistance determining whether a board-only or full pack replacement is appropriate.

Q: What warranty is included? A: 1-year limited manufacturer’s warranty (Master Spas / Balboa).

✅ Why Choose the Master Spas® X801115 (Balboa® 55241)

✅ Genuine OEM circuit board — Balboa-manufactured for Master Spas
✅ MS1600R1A chip — VS501SZ platform
✅ Multi-brand compatibility — Twilight Series, Down East, H2X, Legend, Michael Phelps Swim Spas
✅ Broad year range — models from 2008 through 2017 covered
✅ Factory-new — never installed
✅ 1-year limited manufacturer’s warranty

🤝 Why Buy from Parts4Tubs

✅ Fast US shipping
✅ Chip number, control box, and model compatibility verification available
✅ Daughter board kit (X300026) and complete pack (X300786) available if needed
✅ Competitive pricing

🔌 Summary

The Master Spas® X801115 (Balboa® 55241/55240, chip MS1600R1A, control boxes 55420/55543-01/MS1600H4) is the OEM replacement circuit board for MS1600 VS501SZ systems used in Twilight Series (2009, 2014–2017), Down East Spas® (2009–2010), H2X Swim Spas (2008–2011 and 2015–2017), Legend Series LSX 557 (2008–2012), and Michael Phelps Swim Spas (2012–2013 and 2016–2017). Board dimensions: 11.0″ L × 5.0″ H, 2.1125 lbs. The physical PCB displays “22972_E VS500Z COPYRIGHT 2007” — this is normal. No documentation is included — obtain the wiring schematic from your spa pack cover. Daughter board kit X300026 sold separately if applicable. Non-returnable; 1-year manufacturer’s warranty.

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 are looking for things like setting the voltage as a lot of PCBs can be configured to run on both 115V and 230V.

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.

You turn on the hot tub and it trips the breaker – it is not common for a new PCB to fail out of the box (I have not seen one yet!) However, a common mistake is that the voltage has not been set correctly. If it is set for 115V and then you try and turn it on, the current draw will be a lot more (twice) than expected and the breaker will trip.

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. As mentioned, if the pack is set to 115V and your pump is meant for 230V, it will draw twice the current at half the voltage and trip your breaker. Check the manual for info on how to set the voltage.