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In.Grid External Heater Controller ACM0881 - Bubbles Supply

In.Grid External Heater Controller ACM0881

Part #: ACM0881

$354.21
In stock — ships today
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1-year warrantySame-day ship before 3pm CTPerfect Fit Guarantee30-day returns

About this heater

The In.Grid External Heater Controller ACM0881 is a genuine Wellis OEM replacement part designed for compatible Wellis spa systems. This essential controller manages your spa's heating system while providing a 4-way connector for streamlined electrical connections. The ACM0881 effectively resolves common heater issues including HH (high heat) and OH (overheat) error codes that can disrupt your spa experience.

At Bubbles Supply, we guarantee this controller is the exact fit for your Wellis spa system. Every ACM0881 ships same-day when ordered before our cutoff time and comes backed by our comprehensive 1-year warranty for complete peace of mind. Our genuine OEM parts ensure reliable performance and proper integration with your existing spa components.

Professional installation is recommended for this electrical component. Always verify your spa's model compatibility and consult your owner's manual before installation to ensure proper fitment and safe operation.

Exact part number

ACM0881

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Also known as / Replaces

This part replaces or is interchangeable with:

  • ACM0881 Heater Controller
  • External Heater Control Module
  • In.Grid Heater Controller

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 (high heat) error code on spa display
  • OH (overheat) error code on spa display
  • Spa not reaching or maintaining set temperature
  • Heater cycling on and off erratically
  • Spa control panel showing persistent heater fault
  • Heater not activating despite pump running normally

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

Before you buy — quick checklist

  • Confirm your spa is a Wellis In.Grid system before ordering — this is a brand-specific OEM part
  • Check your existing controller for the ACM0881 part number before purchasing
  • Verify the error code displayed is HH or OH — other codes may indicate a different failed component
  • Inspect the 4-way connector and wiring harness on the existing unit for damage before assuming the controller is the fault
  • If your spa has never been serviced, rule out a faulty temp sensor or flow switch before replacing the controller

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

Install difficulty: Hard — Technician recommended

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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