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76" MSPA/TSPA Hi-Limit Sensor 9920-400684 - Bubbles Supply

76" MSPA/TSPA Hi-Limit Sensor 9920-400684

Part #: 9920-400684

$141.89
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1-year warrantySame-day ship before 3pm CTPerfect Fit Guarantee30-day returns

About this sensor

The 76" MSPA/TSPA Hi-Limit Sensor 9920-400684 by Gecko Alliance is an OEM safety sensor designed for MSPA and TSPA spa systems. This critical component monitors water temperature and automatically shuts down your spa when temperatures exceed safe limits, preventing overheating damage. Featuring a 76-inch cable length with a 1/4-inch bulb sensor, this genuine Gecko part helps resolve HH, ICE, and OH error codes that indicate high-limit sensor issues.

Built to exact OEM specifications, this hi-limit sensor delivers the precise fit and reliable performance your spa demands. Bubbles Supply backs every sensor with our exact fit guarantee, same-day shipping on in-stock orders, and a full 1-year warranty for complete peace of mind. The extended 76-inch cable provides flexible installation options while maintaining optimal sensor placement. Verify your existing sensor's cable length and bulb diameter before ordering to ensure proper fitment in your spa's control system.

Exact part number

9920-400684

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Also known as / Replaces

This part replaces or is interchangeable with:

  • Hi-Limit Sensor
  • High Limit Sensor
  • MSPA Hi-Limit
  • Overheat Sensor
  • Temperature Safety Sensor
  • TSPA Hi-Limit

Looking for an older part number? Check our supersession lookup tool

Common symptoms this part fixes

If your spa is showing any of these signs, this part is likely your fix:

  • HH error code displayed on topside panel
  • OH error code displayed on topside panel
  • ICE error code displayed on topside panel
  • Spa shuts down unexpectedly before reaching set temperature
  • Spa will not heat and displays a fault code
  • Control system reports overtemp condition when water is not actually hot

Not sure if this is your problem? Try our diagnostic centre or .

Before you buy — quick checklist

  • Measure your existing sensor's cable length — this is a 76-inch lead, confirm your routing requires that length
  • Verify your existing bulb diameter is 1/4-inch before ordering
  • Confirm your spa pack is an MSPA or TSPA series Gecko control system
  • Check that your existing sensor uses the same connector type as this OEM replacement
  • Diagnose the sensor with a multimeter before replacing — a faulty heater or board can generate the same error codes

Reading the checklist now prevents 90% of returns. Worth the 60 seconds.

Install difficulty: Medium — Some experience neededTypically 30–60 minutes

What's in the box

  • 76" Hi-Limit Sensor with 1/4-inch bulb
  • OEM Gecko connector plug

If your order is missing any items listed above, contact hello@bubblessupply.com within 48 hours of delivery.

Warranty

1 year manufacturer warranty against defects

Covers manufacturing defects. Does not cover improper installation, normal wear, or accidental damage.

Warranty claims: warranty@bubblessupply.com

Perfect Fit Guarantee

Ordered with our help and the part doesn't fit? Contact us before installation. We'll resolve it with an exchange, replacement recommendation, or return approval.

Learn about our Perfect Fit Guarantee →

Shipping

We ship across the US and Canada. US orders ship from our US warehouse to US customers; Canadian orders ship from our Canadian warehouse to Canadian customers — no cross-border shipping, no surprise duties. In-stock orders placed before 3pm CT ship same day. Standard shipping $9.95 flat rate. Free shipping on orders over $200. Express options available at checkout.

Returns

30-day hassle-free returns on unused parts in original packaging. Contact us before returning to receive your RMA number.

Frequently asked questions

Check the Compatibility section above to confirm fitment for your spa brand and model. If your model is not listed, use our fitment selector at /pages/find-my-part or ask our parts AI for a personalized recommendation.

In-stock orders placed before 3pm CT ship the same day. You will receive tracking information by email as soon as your order ships.

We accept returns within 30 days of delivery for unused items in original packaging. Email returns@bubblessupply.com with your order number to start a return. Installed electrical parts cannot be returned for safety reasons.

Yes, all new parts come with a 1-year warranty against manufacturing defects. Warranty does not cover damage from improper installation or normal wear and tear.

Customer reviews

AI Fitment Assistant

Tell us your spa model and we will confirm this part fits before you buy.

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