�� Balboa BP100UX Spa Circuit Board — G1310 Restore your hot tub with this versatile genuine replacement board for BP100-series spa control systems ⚡ Product Overview The Balboa BP100UX Circuit Board (G1310) is a genuine Balboa Water Group main PCB designed as the universal replacement for the entire BP100 control board family. A single G1310 board consolidates three previously separate systems — the BP100G1, BP100G2, and BP100G3 — into one configurable platform with an optional user-installed expander board. The expander board mounting hardware is pre-installed on the board from the factory, giving technicians everything they need to add a pump or blower output without modifying the enclosure. The BP100UX governs all core hot tub functions including single and two-speed pump operation, dedicated circulation pump filtration and polling, blower control, ozone, spa light, audio/visual output, and precise temperature management across dual Hi/Lo ranges. It supports both 240VAC and, uniquely among compact Balboa boards, 120VAC power input for Setups 5 through 7 — making it one of the most versatile replacement boards in the BP-series lineup. Compatible with the full range of Balboa topside control panels from the simple TP200 series through the TP900 and all spaTouch® graphic display families, this board also supports Balboa Bluetooth Audio (bba™ and bba™2) and optional ControlMySpa Wi-Fi connectivity. Whether you are replacing a failed BP100G1, BP100G2, or BP100G3 board, the G1310 is the current genuine OEM replacement that covers all three. �� Key Features ✅ Single Board Replaces Three Systems — The BP100UX (G1310) is the unified replacement for BP100G1, BP100G2, and BP100G3 spa control boards; one correct part number covers the entire BP100 family ✅ Dual Voltage Capability — Operates on 240VAC (Setups 1–6) or 120VAC (Setups 5–7 only), with built-in jumpers for heater voltage selection — highly versatile for both standard and plug-in spa configurations ✅ Expander Board Hardware Pre-Installed — Mounting hardware for the optional X-P (Pump 2) or X-B (Blower) expander board is factory-fitted to the board; no enclosure modifications required to add a pump or blower output ✅ Pump & Blower Expansion Ready — Supports optional X-P expander (PN 59232) for a 1-speed Pump 2 in Setups 1 & 2, and X-B expander (PN 59231) for a 1-speed Blower in Setups 3 & 4 ✅ Dedicated Circulation Pump Output — 240VAC (or 120V), 2A max; programmable filtration cycles plus polling keep water clean and temperature accurate between user sessions ✅ 7 Software Setup Configurations — Covers circ/non-circ, 1-speed/2-speed Pump 1, Pump 2, and Blower combinations; shipped in Setup 6 by default and field-configurable via DIP switch and topside panel ✅ Wide Topside Panel Compatibility — Works with TP200T/W, TP400T/W, TP500, TP600, TP800, TP900, and all spaTouch™ graphic display families; supports Simplified Menu mode for TP400/500/600 panels ✅ Bluetooth Audio Ready — Supports bba™ (TP800/TP900/spaTouch) and bba™2 (TP800 v4.11 /spaTouch v2.0 ) Balboa Bluetooth Amp integration ✅ Wi-Fi Connectivity Support — Optional ControlMySpa Wi-Fi module connects via J34 or J35; requires DIP switch A7 in OFF position (Standard Menus) ✅ UL Listed — UL System Models BP1-BP100UX-BU (5.5kW), BP1-BP100UX-BS (4.0kW), and BP1-BP100UX-B (remote heater) ✅ 1-Year Manufacturer Warranty — Backed by Balboa Water Group’s standard 1-year limited warranty on PCB components �� Technical Specifications Specification Value Manufacturer Part Number G1310 System Part Numbers 59293-01 (5.5kW integral), 59294-01 (4.0kW integral), 59295-01 (Remote Heater) Replacement PCBA 59499 Board Platform BP100UX (replaces BP100G1, BP100G2, BP100G3) Board Type Main PCB / Control Board Chip Number BP100UXR3A Software Version M100_230 V52.0 Primary Input Voltage 240VAC, 50/60Hz (Setups 1–6) Alternative Input Voltage 120VAC, 50/60Hz — Setups 5–7 ONLY Maximum Service Amperage (240V) 48A Circuit Breaker (240V) 60A maximum Service Amperage (120V, wall-mount GFCI) 16A (20A breaker max) Service Amperage (120V, GFCI cord) 12A maximum Wiring Configuration (240V) 4-wire: Hot, Hot, Neutral, Ground Minimum Wire Gauge #6 AWG copper, 90°C rated Terminal Block Torque (TB1) 27–30 in. lbs. Heater Connection Torque 30–35 in. lbs. Pump 1 Output 240VAC, 2-Speed (1-Speed in Setups 1, 3, 5), 12A max Pump 2 Output 240VAC, 1-Speed, 12A max — Setups 1 & 2 via X-P expander (PN 59232) Blower Output 240VAC, 1-Speed, 4A max — Setups 3 & 4 via X-B expander (PN 59231) Circulation Pump Output 240VAC (or 120V), 1-Speed, 2A max Ozone Output 240VAC (or 120V), 0.5A max Spa Light Output 10VAC, On/Off, 1A max A/V (Stereo) Output 120VAC, 3A max (always on) Heater — 5.5kW Version 5.5kW @ 240VAC (approx. 1.4kW @ 120VAC) Heater — 4.0kW Version 4.0kW @ 240VAC (1.0kW @ 120VAC) Heater Flow Requirement Minimum 20 GPM through heater Software Setups 7 (Ships in Setup 6) Hi-Range Temperature 80°F–104°F (26.7°C–40°C) Lo-Range Temperature 50°F–99°F (10°C–37.2°C) Freeze Protection Threshold 44°F (6.7°C) GFCI Class A GFCI required; internal GFCI trip detection supported Certifications UL (System Models BP1-BP100UX-BU, BP1-BP100UX-BS, BP1-BP100UX-B) Warranty 1 Year (Balboa Water Group) Physical Dimensions Please refer to manufacturer documentation or contact Parts4Tubs Operating Temperature Range Please refer to manufacturer documentation or contact Parts4Tubs ⚠️ US Voltage Note: This is a North American UL-listed board. The 240VAC input is standard for Setups 1–6. The 120VAC option applies to Setups 5–7 only and requires specific wiring changes and jumper adjustments. Always verify your spa’s electrical configuration before ordering. ⚠️ Voltage Rule: Pump 1, Circ Pump, and Ozone MUST all be the same voltage — all 240VAC or all 120VAC. �� Compatibility Guide Systems This Board Replaces System Description BP100G1 Earlier BP100 single-board configuration BP100G2 BP100 system with pump expander support BP100G3 BP100 system variant BP100UX Current unified platform (direct match) Cross-Reference Part Numbers Part Number Description G1310 Balboa Water Group — current main PCB part number G4311 System kit variant 59499 Main PCBA replacement number 59293 / 59293-01 Complete system — 5.5kW 800 Incoloy integral heater 59294 / 59294-01 Complete system — 4.0kW 800 Incoloy integral heater 59295 / 59295-01 Complete system — Remote heater (heater sold separately) 59494 System variant reference 33-59494-K Kit variation Compatible Topside Control Panels Panel Minimum Version spaTouch™2 Any version (v2.0 for bba™2) Icon spaTouch™ Any version (v3.36 for bba™2) Menued spaTouch™ Any version (v2.8 for bba™2) TP900 Version 3.1 (v3.13 for bba™) TP800 Version 3.1 (v3.13 for bba™; v4.11 for bba™2) TP600 Version 2.7 (v2.12 for bba™/bba™2 menu control) TP500 Any version TP400T (US) Version 2.7 (v2.12 for bba™/bba™2 menu control) TP400W (US) Version 2.7 (v2.12 for bba™/bba™2 menu control) TP200T Any version TP200W Any version ⚠️ Panel note: TP800 is not supported in Setup 7. TP600 is not supported in Setup 7. Do not use graphic panels (TP800, TP900, spaTouch™) with Simplified Menus (DIP Switch A7 ON). ⚠️ Always verify your existing board’s part number before ordering. Do not select a replacement board based on appearance — many Balboa boards look similar but contain different software. ��️ Board Functions & Controls Pump Control Output Connector Setup Availability Voltage Rating Pump 1 (2-Speed) J9 Setups 2, 4, 6 240VAC 12A max Pump 1 (1-Speed) J9 Setups 1, 3, 5 240VAC 12A max Pump 1 (unused) — Setup 7 only — — Pump 2 (1-Speed) J4 via X-P expander Setups 1 & 2 only 240VAC 12A max Blower (1-Speed) J3 via X-B expander Setups 3 & 4 only 240VAC 4A max Circ Pump J19 Setups 1, 3, 5, 7 240VAC (or 120V) 2A max Heater Control Feature Specification Heater Type Balboa Incoloy electric element (800 Incoloy) 5.5kW Version 5.5kW @ 240VAC; Heater PN 58421 (integral) 4.0kW Version 4.0kW @ 240VAC; Heater PN 58426 (integral) Remote Heater Sold separately; see system PN 59295-01 Hi-Range Set Temp 80°F–104°F (26.7°C–40°C); default 100°F Lo-Range Set Temp 50°F–99°F (10°C–37.2°C); default 70°F Hi-Limit Protection Built-in via Sensor A and Sensor B Dry Heater Protection Built-in detection circuit Minimum Flow 20 GPM through heater Heater Torque 30–35 in. lbs. at heater connections Additional Outputs Function Connector Specification Spa Light J15 10VAC, 1A max, 240-minute auto-timer Ozone J21 0.5A max; slaved to circ pump (circ setups) or P1 Low (non-circ) A/V (Stereo) J33 120VAC, 3A max, always on Wi-Fi Module J34 or J35 Optional ControlMySpa module Freeze Protection Automatic 44°F threshold; pumps rotate at lowest speed Setup Reference Table Setup # Circ Pump Pump 1 Pump 2 Blower Expander Needed Notes 1 Filtration Polling 1-Speed 1-Speed — X-P (PN 59232) Circ is heater pump 2 — 2-Speed 1-Speed — X-P (PN 59232) P1 is heater pump 3 Filtration Polling 1-Speed — 1-Speed X-B (PN 59231) Circ is heater pump 4 — 2-Speed — 1-Speed X-B (PN 59231) P1 is heater pump 5 Filtration Polling 1-Speed — — None 120V capable 6 — 2-Speed — — None Default shipped setup; 120V capable 7 Filtration Polling — — — None Circ pump only; 120V capable DIP Switch Functions Switch OFF Position ON Position A1 Test Mode OFF Test Mode ON A2 No 1 HS pump with heater Add 1 high-speed pump with heater A3 No 2 HS pumps with heater Add 2 high-speed pumps with heater A4 1-min heater cooldown (electric) 5-min heater cooldown (gas) A5 Special Amperage Rule A Special Amperage Rule B A6 Persistent memory retained Persistent memory reset on power-up A7 Standard Menus (compatible with all panels) Simplified Menus (TP400/500/600 only — NOT with graphic panels) �� Installation Requirements ⚠️ IMPORTANT: All electrical work must be performed by a licensed electrician in compliance with the National Electrical Code (NEC) Article 680 and all applicable local codes. Pre-Installation Checklist [ ] Confirm the existing board is a BP100G1, BP100G2, BP100G3, or BP100UX system [ ] Note the current Setup number from the label inside the system lid [ ] Confirm heater size (4.0kW or 5.5kW) and whether it is an integral or remote heater [ ] Confirm supply voltage (120V or 240V) — especially for Setups 5–7 [ ] Disconnect ALL power at the circuit breaker and GFCI before beginning [ ] Photograph all wiring and connector positions before removing the old board [ ] Allow capacitors to discharge — wait at least 5 minutes after power-off Electrical Requirements Requirement Specification Supply Voltage (standard) 240VAC / 60Hz Supply Voltage (120V option) 120VAC — Setups 5–7 ONLY Circuit Breaker (240V) 60A maximum Circuit Breaker (120V, wall-mount GFCI) 20A maximum Circuit Breaker (120V, GFCI cord) 15A (service limited to 12A) GFCI Protection Class A GFCI required — NEC Article 680-42 Ground Connection Equipment grounding and bonding required — NEC Article 680 Bonding Conductor Solid copper to all metal within 5 ft of spa Minimum Wire Gauge #6 AWG copper, 90°C rated Dedicated Circuit Required Disconnect Within line of sight of spa, at least 5 ft from water (NEC) Terminal Torque TB1: 27–30 in. lbs.; Heater connections: 30–35 in. lbs. Key Jumpers Jumper Function J24 Center pins = 240V heater; outer pins = 120V heater J31 1 pin = 120V heater; 2 pins = 240V heater J109 GFCI Test/Trip Enable/Disable ⚠️ Critical: J24 and J31 must both be set correctly for the heater voltage. F3 fuse must also be changed: 0.1A for 240V heater, 0.16A for 120V heater. Always set DIP Switches A2 and A3 to OFF when using 120VAC configuration. �� Tip: Write the Setup number on the label inside the system lid using a permanent marker — essential for any future service. ⚠️ Safety Warnings Electrical Safety: ⚠️ ALWAYS disconnect ALL power at the breaker and GFCI before touching any wiring ⚠️ Installation MUST be performed by a licensed electrician only ⚠️ Verify supply voltage (120V or 240V) matches the selected setup before connecting ⚠️ Class A GFCI protection is mandatory per NEC Article 680-42 ⚠️ Use copper conductors ONLY — no aluminum wiring ⚠️ A dedicated circuit and disconnect within line of sight of the spa are required by NEC ⚠️ Never operate spa with covers removed from the electrical control enclosure Board-Specific Warnings: ⚠️ Pump 1, Circ Pump, and Ozone MUST all be the same voltage — mixing voltages will cause damage ⚠️ Do NOT use graphic panels (TP800, TP900, spaTouch™) with Simplified Menus (DIP A7 ON) ⚠️ Setups 1–4 require an expander board (X-P or X-B); do NOT run these setups without the appropriate expander installed ⚠️ Jumpers J24 and J31 AND fuse F3 must all be set correctly for the heater voltage ⚠️ Setting DIP switches incorrectly may cause abnormal system behavior or component damage Post-Installation: ⚠️ Run Priming Mode and verify all pumps are primed before heater activation ⚠️ Test GFCI function, hi-limit sensor, and freeze protection before first use ⚠️ Check topside display for error codes on initial startup �� Error Codes & Troubleshooting Common Topside Messages Code Meaning First Action dr Heater may be dry — will retest Check water level, filter, valves, pump prime, flow rate drY / dY Verified dry heater — spa disabled Resolve flow issue; press any button to reset CFE / CONFIG ERROR DIP switch configuration conflict Check DIP switch settings match equipment; A7 must be OFF with graphic panels CrC / CHKSUM FAIL Firmware checksum error at power-up Power off/on; if repeated, contact dealer – – – Water temperature unknown Normal — wait 2 minutes with heater pump running Sn / SN Sensor fault Check sensor connections; swap Sensor A and B to isolate fault Troubleshooting Quick Reference Symptom Likely Cause First Step Nothing operates Breaker off / GFCI tripped Reset breaker and GFCI No heat Low flow, wrong setup, or wrong voltage Check filter, water level, heater voltage jumpers, Setup selection GFCI trips immediately Wiring fault or improper GFCI install Contact licensed electrician Pump 2 not responding X-P expander not installed or wrong setup Verify Setup 1 or 2 is selected; confirm X-P expander (59232) is installed Blower not responding X-B expander not installed or wrong setup Verify Setup 3 or 4 is selected; confirm X-B expander (59231) is installed Display shows “T” after temp reading Test Mode active (DIP Switch A1 ON) Move A1 to OFF to exit Test Mode Panel menus not working as expected A7 Simplified Menus set on graphic panel Turn A7 to OFF for use with TP800/TP900/spaTouch™ ⚠️ Always refer to the official Balboa BP100UX Tech Sheet for complete diagnostic procedures. Contact Parts4Tubs technical support for additional assistance. �� Ideal Applications Application Suitability Notes ♨️ Replacing failed BP100G1 board ✅ Direct replacement Configure setup to match existing equipment ♨️ Replacing failed BP100G2 board ✅ Direct replacement Configure setup to match existing equipment ♨️ Replacing failed BP100G3 board ✅ Direct replacement Configure setup to match existing equipment ♨️ Replacing failed BP100UX board ✅ Exact replacement Match to existing Setup number ♨️ Spa with 1-pump and circ setup ✅ Setup 1 or 5 X-P expander needed in Setup 1 ♨️ Spa with 1-pump, no circ (standard 240V) ✅ Setup 6 (default) No expander needed ♨️ Spa with 2 pumps ✅ Setups 1 or 2 with X-P expander X-P (PN 59232) must be installed ♨️ Spa with pump blower ✅ Setups 3 or 4 with X-B expander X-B (PN 59231) must be installed ♨️ 120V plug-in portable spa ✅ Setups 5, 6, or 7 only Requires specific wiring and jumper changes ♨️ Spa with ControlMySpa Wi-Fi ✅ Supported Wi-Fi module connects to J34 or J35; A7 must be OFF ❓ Frequently Asked Questions Q: How do I know if this board fits my spa? A: Check your existing board’s part number against the compatibility list. If your board shows BP100G1, BP100G2, BP100G3, or BP100UX, or any of the system numbers (59293, 59294, 59295, 59499), the G1310 is the correct replacement. Contact Parts4Tubs with your system label if unsure. Q: Is this an OEM or aftermarket board? A: This is a genuine OEM Balboa Water Group circuit board. The BP100UX was specifically designed by Balboa as the universal replacement for the entire BP100 board family. Q: What is the difference between the 5.5kW and 4.0kW versions? A: The heater output capacity differs, but the main PCBA (G1310 / 59499) is the same for both. The heater assembly itself and the F3 fuse rating may differ. When ordering just the replacement circuit board (G1310), the board itself is the same; you need to retain your existing heater and configure the jumpers (J24, J31) to match it. Q: Do I need a licensed electrician to install this? A: Yes. NEC Article 680 requires a licensed electrician for all spa electrical work in most US jurisdictions. A permit may also be required. Incorrect installation can cause fire, electrocution, or equipment damage. Q: My spa ran on 120V — does this board support that? A: Yes, but only for Setups 5, 6, and 7. When configured for 120VAC, specific wiring changes are required, DIP Switches A2 and A3 must be OFF, jumpers J24 and J31 must be moved to 120V positions, and fuse F3 must be changed to the 0.16A slow-blow version (supplied with the system). Contact Parts4Tubs to confirm your setup is compatible. Q: What is the difference between Setups 5 and 6? A: Both support 120V operation with a single 2-speed (Setup 6) or 1-speed (Setup 5) Pump 1 and no expander. The key difference is that Setup 5 includes a dedicated circulation pump for filtration and polling, while Setup 6 uses Pump 1 low-speed for heating with no circ pump. Q: Do I need to purchase the expander board separately? A: If your spa uses two pumps or a blower (Setups 1–4), yes — you need to purchase the appropriate expander board: X-P (PN 59232) for Pump 2 or X-B (PN 59231) for a blower. The G1310 board comes with the mounting hardware pre-installed, but the expander board itself is a separate purchase. If your spa only uses a single pump with no blower (Setups 5–7), no expander is needed. Q: Will my existing topside panel work with this board? A: Compatible panels include all TP200, TP400, TP500, TP600, TP800, TP900, and spaTouch™ series panels. If using graphic panels (TP800, TP900, spaTouch™), ensure DIP switch A7 is set to OFF (Standard Menus). Contact Parts4Tubs with your topside model if uncertain. Q: What warranty is included? A: Balboa Water Group provides a 1-year limited warranty against defects in materials and workmanship from the date of purchase. Contact Parts4Tubs for warranty claim assistance. Q: What if I get error codes after installation? A: The most common post-installation issues involve incorrect setup selection, jumper configuration, or voltage mismatches. Verify Setup number, J24/J31 jumper positions, DIP switch settings (especially A2/A3 for 120V systems), and sensor connections. Contact our technical support team for guided troubleshooting. �� Downloads & Resources �� Balboa BP100UX Tech Sheet (Official Manufacturer PDF) — Complete specifications, setup tables, wiring diagrams, DIP switch definitions, and fuse part numbers �� Why Choose the Balboa BP100UX (G1310)? ✅ One Board Covers All Three BP100 Generations — Eliminates the need to identify whether you have a G1, G2, or G3 board; the G1310 is the correct replacement for all of them ✅ Factory-Fitted Expander Mounting Hardware — The board ships ready to accept the optional X-P or X-B expander; no drilling or enclosure modification needed ✅ Dual Voltage Flexibility — The only compact Balboa main board in its class that supports both 240VAC and 120VAC (Setups 5–7), covering plug-in portable spas and hardwired installations ✅ Full Smart-Technology Support — Supports ControlMySpa Wi-Fi, Balboa Bluetooth Audio (bba™ and bba™2), and audio/visual output — all from a single compact board ✅ UL Listed — North American safety certification through three UL System Models covering all heater configurations ✅ Built-In Safety — Class A GFCI trip detection, freeze protection at 44°F, dual sensor A/B hi-limit monitoring, and heater dry-detection — all integrated into board logic ✅ Broad Panel Support — From the simplest TP200 two-button panel to the full spaTouch™3 graphic display, every current Balboa panel works with this board ✅ 1-Year Manufacturer Warranty — Backed by Balboa Water Group �� Why Buy From Parts4Tubs? ✅ US-based company with expert local support ✅ Fast US shipping on in-stock parts ✅ Spa specialists available for technical advice and compatibility verification ✅ Competitive pricing on genuine Balboa OEM parts ✅ Full warranty support — we handle claims with the manufacturer on your behalf ✅ Easy returns within 30 days on eligible items ✅ Compatible accessories available — topside panels, expander boards (X-P and X-B), sensors, heater kits, Wi-Fi modules, and more ✨ Summary The Balboa BP100UX Circuit Board (G1310) is the genuine OEM replacement for the entire BP100 control board family — BP100G1, BP100G2, and BP100G3 — unified into one versatile, field-configurable board. With 7 software setups, dual 120V/240V capability, factory-fitted expander mounting hardware, support for pump and blower expansion, and compatibility with every Balboa topside panel including Wi-Fi and Bluetooth Audio, it is the complete, correct solution for restoring any BP100-series spa. UL listed, backed by a 1-year warranty, and available now from Parts4Tubs with expert technical support. Order today and get your spa back in action. Parts4Tubs is proud to be a Balboa Authorized Online Seller - make sure you only buy genuine Balboa parts from trusted sources. 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.