⚡ Sundance / Jacuzzi 6600-722 Spa Circuit Board – LX-10 Rev 5.03+ (1-Pump, No Circulation Pump)

OEM-quality LX-10 replacement board to restore reliable control of your Sundance or Jacuzzi hot tub.

💧 Product Overview

The 6600-722 is the updated replacement circuit board for 1-pump Sundance® and Jacuzzi® hot tubs running the Spa Builders LX-10 control system (Revision 5.03 and later, including the 5.57+ update). It is a factory-updated version that directly replaces the older 6600-042, 6600-089, 6600-289, and 6600-082 boards, and adds surface-mount heater terminals for improved reliability — while remaining 100% backward-compatible with the systems that used those earlier boards.

This PCB runs the heater, the 2-speed jet pump, the ozone circuit, and the spa light, and communicates with the topside LCD panel to manage temperature, filter cycles, freeze protection, and diagnostics. It is the correct board for spas without a separate 24-hour circulation pump — if your spa has a circulation pump, you need the 6600-724 / 6600-726 variant instead.

Installing the genuine replacement restores full heating, jet, light, and safety-sensor function and clears persistent watchdog (—), FL1, and SN-series fault conditions caused by a failing board.

⭐ Key Features

• ✅ Direct fit, 1-pump LX-10 systems – drop-in replacement for 6600-042, 6600-089, 6600-289, and 6600-082 boards
• ✅ Updated heater terminals – newly added surface-mount heater terminals for stronger, more reliable heater connections
• ✅ Three large onboard relays – handles low-speed pump, high-speed pump, and heater switching
• ✅ Voltage-selectable via jumper – configurable for 120V/15A Logic or 240V/40A Logic operation (per PDF jumper settings)
• ✅ Self-diagnostic LX-10 firmware – displays flow, sensor, overheat, freeze, and watchdog conditions on the topside LCD
• ✅ Wide temperature set range – 65°F to 104°F (18°C to 40°C) adjustable in 1°F increments
• ✅ Built-in freeze protection – automatically energizes pump and heater at 55°F (12.8°C)
• ✅ Overheat protection – heater deactivates at 110°F (43.3°C), full system shutdown at 118°F (48°C) watchdog
• ✅ Six programmable filter cycles – three Standard Mode + three Economy Mode, plus system and panel lockout modes
• ✅ Ozone-ready output – drives ozonator during filter cycles when equipped
• ✅ Integrated spa-light control – 1-hour auto time-out
• ✅ Long-established platform – Spa Builders LX-10 has been deployed on Sundance / Jacuzzi spas since the late 1990s

🔧 Technical Specifications

Specification	Value
Part Number	6600-722
Control System	Spa Builders LX-10
Software Revision	5.03+ (also supplied as 5.57+ chip update)
Board Configuration	1-Pump, No Circulation Pump
Onboard Relays	3 large relays (low-speed pump, high-speed pump, heater)
Input Voltage Logic	120V / 15A OR 240V / 40A (jumper-selectable, per LX-10 JP1)
Frequency	60 Hz (US/Canada)
Pump Configuration	2-speed (low/high)
Heater Switching	220 VAC load across heater relay (K7–K6 terminals)
Transformer Secondary	12.4 VAC
Temperature Set Range	65°F to 104°F (18°C to 40°C)
Display Resolution	1°F increments (°F / °C selectable via JP1 3-4 jumper)
Overheat (OH) Trip	110°F (43.3°C)
Watchdog (—) Trip	118°F (48°C)
Freeze (ICE) Protection	Activates at 55°F (12.8°C)
Cool (COL) Threshold	20°F (11°C) below set point (Economy Mode only)
Jets Auto Time-Out	20 minutes (outside filter cycle)
Light Auto Time-Out	1 hour
Compatible Temp Sensor	6600-166 (curled finger connectors)
Compatible Hi-Limit Sensor	6600-068
Connection Type	Push-on (spade) connectors
Returnable	⚠️ No – circuit boards are non-returnable

ℹ️ Voltage note: The LX-10 is a voltage-convertible platform. US Sundance/Jacuzzi spas running this board are most commonly wired for 240V / 60Hz service via a dedicated GFCI-protected circuit, but the same board logic also supports 120V / 15A installations when jumper JP1 pins 1-2 are shorted. Always verify the existing configuration before applying power.

🔗 Compatibility Guide

Compatible Sundance® Spa Models

Series	Models	Years
Sundance 680®	Denali, Tacoma (1-pump, no circ)	2006+
Sundance 680®	Burlington (1-pump, no circ configuration)	2008+
Sundance 680®	Prado, Prado 5 (per some distributors)	2017+
Sundance 780®	Hamilton, Chelsee, Certa, Camden (1-pump)	2007+
Sundance 780®	Palermo, Bahia, Cayman	2005–2006
Sundance Del Sol®	Redondo, Hermosa	2003–2005
Sweetwater®	Aruba, Bali, Cyprus	2000–2002

Compatible Jacuzzi® Spa Models

Series	Models	Notes
Jacuzzi J-200™	J-210, J-220	No circulation pump versions
Jacuzzi Del Sol®	Del Sol LED models	2004+ (replaced 6600-089 / 6600-289 / 6600-042)

OEM Part Numbers This Board Replaces

Old Part Number	Description
6600-042	Earlier-revision Sundance LX-10 1-pump, no circ
6600-089	Earlier-revision Sundance LX-10 1-pump, no circ
6600-289	Earlier-revision Sundance LX-10 1-pump, no circ
6600-082	2000–2001 Sweetwater (Aruba, Bali, Cyprus) LX-10 board
3-60-0098	LX-10 Series equivalent designation

⚠️ Always verify your existing circuit board part number, spa model year, and whether your spa has a 24-hour circulation pump before ordering. If a circulation pump is present, you need the 6600-724 / 6600-726 instead of this board.

🎛️ Board Functions & Controls

Pump Control

Output	Function	Relay
Pump 1 – Low Speed	Circulation / heat-assist / filter cycle	Large onboard relay
Pump 1 – High Speed	Jet action	Large onboard relay
Circulation Pump	❌ Not supported on this board

Heater Control

Feature	Specification
Heater Switching	220 VAC load across K7-com / K6-com
Hi-Limit Protection	Via external 6600-068 hi-limit sensor
Set Range	65°F – 104°F (18°C – 40°C)
Overheat Cut-Off (OH)	110°F (43.3°C) – heater disabled, low-speed pump runs to cool
Watchdog Cut-Off (—)	118°F (48°C) – entire system disabled

Additional Controls

Function	Capability
Spa Light	Integrated on/off, 1-hour auto time-out
Ozone	Energized during filter cycles when spa is equipped
Display Units	°F or °C selectable via JP1 pins 3-4 jumper

Filter Cycle Programs

Program	Mode	Cycle
F1	Standard	2 hrs every 12 hrs
F2	Standard	2 hrs every 8 hrs
F3	Standard	2 hrs every 6 hrs
F4	Economy	2 hrs every 12 hrs
F5	Economy	2 hrs every 8 hrs
F6	Economy	2 hrs every 6 hrs
L1	System Lockout	Pump / blower disabled for service
L2	Panel Lockout	Topside buttons disabled (runs F1)

JP1 Jumper Reference (LX-10)

Pins	Jumper ON	Jumper OFF
1-2	120V / 15A logic	240V / 40A logic
3-4	Centigrade (°C)	Fahrenheit (°F)

🛠️ Installation Requirements

Pre-Installation Checklist

• [ ] Confirm your existing board is a Sundance/Jacuzzi LX-10 1-pump, no-circ variant
• [ ] Confirm your old part number: 6600-722 / 6600-289 / 6600-089 / 6600-042 / 6600-082
• [ ] Disconnect all power at the house breaker AND the spa disconnect box
• [ ] Photograph every wire and connector position on the existing board before removal
• [ ] Allow capacitors to discharge — wait at least 5 minutes after power-off
• [ ] Inspect temperature sensor (6600-166) and hi-limit sensor (6600-068); replace as a set if the spa has thrown sensor fault codes

Electrical Requirements

Requirement	Specification
Supply Voltage	120V / 60Hz or 240V / 60Hz (match the existing spa wiring and JP1 jumper setting)
Circuit Breaker	Per spa manufacturer rating — typically 50A GFCI for 240V installations
GFCI Protection	Required (NEC Article 680)
Grounding	Equipment grounding + bonding required (NEC Article 680)
Dedicated Circuit	Required
Disconnect Box	Required within line of sight of the spa (NEC)

Key Connection Reference Points

Reference (per LX-10 service doc)	Function
K7-com to K6-com	Heater load terminals (220 VAC during heat call)
J4 (Yellow–Yellow)	Transformer secondary output, 12.4 VAC
Sensor plug	6600-166 temperature sensor input
Hi-limit	6600-068 hi-limit snap-switch input
JP1	Voltage and °F/°C configuration jumper

💡 Tip: Label or photograph every push-on connector before removing the old board. Loose or improperly seated connectors cause overheating at the terminal and are a leading cause of repeat board failures — tighten with needle-nose pliers if needed so they grip fully on the pin.

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⚠️ Safety Warnings

Electrical Safety

• ⚠️ ALWAYS disconnect power at the house breaker before any work on the spa pack
• ⚠️ Installation must be done by a licensed electrician
• ⚠️ Verify the supply voltage (120V or 240V) matches the JP1 jumper configuration before energizing
• ⚠️ GFCI protection is mandatory for all hot-tub installations (NEC Article 680)
• ⚠️ Never operate the spa with the control box cover removed
• ⚠️ All wiring must comply with the NEC and local electrical codes

Water & Electrical Safety

• ⚠️ Protect the board and control box from any water ingress during and after installation
• ⚠️ Inspect every seal and gasket on the control-box enclosure before closing up
• ⚠️ Never touch electrical components with wet hands

Post-Installation

• ⚠️ Test hi-limit and temperature sensor response before returning the spa to service
• ⚠️ Verify pump rotation (low and high speeds) and heater call-for-heat indication
• ⚠️ Monitor the topside LCD for any error codes during the first heat cycle

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🔍 Error Codes & Troubleshooting (Spa Builders LX-10)

Code	Meaning	Suggested Action
SN1	Non-functional high-temperature (hi-limit) sensor	Check sensor plug seating. Test 6600-068 resistance. Replace as a matched sensor set if out of spec.
SN2	Non-functional temperature sensor	Check sensor plug seating. Test 6600-166 resistance (decreases as temp rises). Replace if out of spec.
FL1	Water-flow problem — pressure switch did not close with pump running	Check water level, prime pump, clean filter, verify pressure switch operation and adjustment.
FL2	Pressure switch closed while pump is OFF	Pressure switch stuck closed or shorted — test and replace as needed.
COL	Cool condition — water 20°F (11°C) below set point (Economy Mode only)	No action needed; low-speed pump and heater will automatically recover temperature.
ICE	Freeze condition detected at ≤55°F (12.8°C)	No action needed; pump + heater activate automatically until ≥65°F.
OH	High-temperature condition — water ≥110°F (43.3°C)	Do not enter the spa. Low-speed pump will run to cool water. Check filter / flow / filter-cycle timing.
—	Watchdog — water reached 118°F (48°C); full system disable	Shut off spa breaker. Likely bad temperature sensor, hi-limit sensor, board, keypad, or transformer. Call a qualified technician.

Sensor Resistance Quick-Reference (6600-166 / 6600-068)

Water Temp	Resistance (Ω)
68.0°F (20°C)	39,000
77.0°F (25°C)	30,000
86.0°F (30°C)	24,270
95.0°F (35°C)	19,740
104.0°F (40°C)	16,149

(Full Spa Builders sensor resistance table is included in the LX-10 service document.)

🎯 Ideal Applications

Application	Suitability	Notes
♨️ Sundance 680 Denali / Tacoma (1-pump, no circ)	✅ Direct replacement	2006+ models
♨️ Sundance 780 Hamilton / Chelsee / Certa / Camden (1-pump)	✅ Direct replacement	2007+ models
♨️ Sundance 780 Palermo / Bahia / Cayman	✅ Direct replacement	2005–2006
♨️ Sundance Del Sol Redondo / Hermosa	✅ Direct replacement	2003–2005
♨️ Sweetwater Aruba / Bali / Cyprus	✅ Direct replacement	2000–2002
♨️ Jacuzzi J-210 / J-220	✅ Compatible	1-pump, no circ versions
♨️ Jacuzzi Del Sol LED	✅ Direct replacement	2004+
♨️ Any Sundance/Jacuzzi spa with a 24-hour circulation pump	❌ Do not use — order 6600-724 / 6600-726 instead
♨️ 2-pump Sundance/Jacuzzi systems	❌ Not supported — this is a 1-pump board

This board is designed for:

• Replacing a failed 6600-042, 6600-089, 6600-289, or 6600-082 board
• Restoring heater, jet, light, and sensor operation on the above spa models
• Upgrading to the updated surface-mount heater terminal design

❓ Frequently Asked Questions

Q: How do I know if the 6600-722 is the right board for my spa? A: Pull your control-box lid and read the part number printed on the existing PCB. If it reads 6600-042, 6600-089, 6600-289, or 6600-082 — or if the OEM paperwork lists 3-60-0098 / LX-10 1-pump / no circ pump — the 6600-722 is the correct updated replacement.

Q: Is this an OEM board? A: Yes. The 6600-722 is the genuine Sundance®/Jacuzzi® factory replacement board, built on the Spa Builders LX-10 platform. It is the updated part number that supersedes the earlier 6600-042 / 6600-089 / 6600-289 boards and is 100% backward-compatible with those systems.

Q: My spa has a circulation pump — will this board work? A: No. This board is the no-circ-pump variant. Spas that use a 24-hour circulation pump require the 6600-724 / 6600-726 boards instead.

Q: Do I need a licensed electrician to install this? A: Yes. NEC Article 680 and most local codes require a licensed electrician for any spa/hot-tub electrical work, and a permit is often required depending on jurisdiction. Servicing the control pack also requires confirming the 120V/240V jumper configuration.

Q: Will my existing topside panel work? A: If your current topside is the original LX-10-compatible Sundance/Jacuzzi LCD panel for your spa model, it will work. Contact Parts4Tubs with your topside part number if you are unsure.

Q: Does this board support 120V or 240V? A: Both. Jumper JP1 pins 1-2 select between 120V / 15A logic (jumper ON) and 240V / 40A logic (jumper OFF). Most US residential Sundance/Jacuzzi spas using this board are wired for 240V / 60Hz. Always match the jumper to your spa’s wired supply voltage.

Q: Can I return it if it doesn’t fix the problem? A: ⚠️ No. Circuit boards are non-returnable — they cannot be resold as new once they have been installed or powered on. Please verify compatibility carefully before purchase and contact our team if you need help identifying the correct board.

Q: What sensors do I need? A: Temperature sensor 6600-166 (curled finger connectors) and hi-limit sensor 6600-068. Both are sold separately and should be replaced as a matched set if your spa has thrown SN1 or SN2 fault codes.

🏆 Why Choose the 6600-722

• ✅ Genuine OEM Sundance®/Jacuzzi® replacement board
• ✅ Direct drop-in for 6600-042, 6600-089, 6600-289, and 6600-082
• ✅ Factory-updated surface-mount heater terminals for improved connection reliability
• ✅ Voltage-selectable for 120V or 240V installations
• ✅ Built-in freeze, overheat, and watchdog protection
• ✅ Proven Spa Builders LX-10 platform with documented service procedures
• ✅ Supports the full 65°F – 104°F spa temperature range

🇺🇸 Why Buy From Parts4Tubs

• ✅ US-based company with local technical support
• ✅ Fast US shipping
• ✅ Expert advice from spa specialists — we’ll help you identify the correct board
• ✅ Competitive pricing on genuine OEM parts
• ✅ Manufacturer warranty support
• ✅ Matching sensors (6600-166, 6600-068) and topside panels in stock
• ✅ Real help matching spa make, model, year, and existing PCB part number

✨ Summary

The Sundance/Jacuzzi 6600-722 is the factory-updated LX-10 replacement circuit board for 1-pump hot tubs without a circulation pump. It drops straight in for the older 6600-042, 6600-089, 6600-289, and 6600-082 boards, drives a 2-speed jet pump, heater, ozone, and spa light, and ships with proven LX-10 diagnostics and freeze / overheat / watchdog protection. Order with confidence for Sundance 680, 780, Del Sol, Sweetwater, and Jacuzzi J-200 / Del Sol LED spas — and note this board is non-returnable, so verify fit before purchase.

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.