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Spa Test Switch 6600-999 - Bubbles Supply

Spa Test Switch 6600-999

Part #: 6600-999

$23.34
In stock — ships today
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1-year warrantySame-day ship before 3pm CTPerfect Fit Guarantee30-day returns

About this hardware/other

The Spa Test Switch 6600-999 is an OEM service test plug designed for Sundance Spas systems. This essential diagnostic sensor allows technicians to troubleshoot and test spa functions, helping resolve common error codes including HH (high limit), ICE (freeze protection), and OH (overheat) conditions. As a genuine Sundance replacement part, it ensures reliable performance and accurate system diagnostics.

At Bubbles Supply, we guarantee this test switch will fit your Sundance spa exactly as intended. Every order ships same-day from our Canadian warehouse and includes our comprehensive 1-year warranty for complete peace of mind. This OEM sensor maintains the precise specifications required for proper spa operation and diagnostic accuracy. Verify your spa's part number matches 6600-999 before ordering to ensure proper fitment and optimal performance.

Exact part number

6600-999

Save this for ordering or warranty claims

Also known as / Replaces

This part replaces or is interchangeable with:

  • jumper test plug
  • service test switch
  • spa diagnostic plug
  • Sundance test plug

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:

  • Persistent HH (high limit) error code that won't clear
  • False OH (overheat) fault triggering shutdown
  • ICE freeze protection code triggering in normal conditions
  • Unable to isolate whether fault is sensor-side or control board-side
  • Spa locks out after reset and won't hold normal operation

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

Before you buy — quick checklist

  • Confirm your spa control system is a genuine Sundance Spas unit before ordering
  • Verify part number 6600-999 appears on your existing test switch or service documentation
  • This is a diagnostic service tool — confirm you need a test plug, not the actual sensor being tested
  • Have your spa's error code history on hand before using this tool to narrow down the fault source
  • Consult your Sundance service manual to confirm the correct test procedure for your specific board generation

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

Install difficulty: Medium — Some experience neededTypically 15-30 minutes

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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