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4 HP Viper Spa Pump 2 Speed 230V 3721621-1V (MV-40226-25) 4.00HP 230V - Bubbles Supply

4 HP Viper Spa Pump 2 Speed 230V 3721621-1V

Part #: 3721621-1V

$879.43
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About this spa pump

The Waterway Viper 4HP 2-Speed Spa Pump delivers powerful, reliable circulation for larger residential spas and hot tubs. This 230V main pump features dual-speed operation with 12.0/4.4 amp draw, providing high-flow filtration on speed one and energy-efficient circulation on speed two. The 56Y frame design ensures compatibility with standard spa equipment pads.

Built to OEM specifications, this genuine Waterway replacement pump comes with our exact fit guarantee and ships same-day from our Canadian warehouse. Every Viper pump includes our comprehensive 1-year warranty for complete peace of mind. Before installation, verify your existing pump's horsepower, voltage, and plumbing configuration match this unit's specifications to ensure proper fit and performance.

Exact part number

3721621-1V

Save this for ordering or warranty claims

Also known as / Replaces

This part replaces or is interchangeable with:

  • MV-40226-25

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

Technical specifications

Voltage
230V
Horsepower
4.0 HP
Frame size
56Y frame
Speed
Two-speed
Amperage
12.0A/4.4A

Common symptoms this part fixes

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

  • Pump won't start
  • Humming but no rotation
  • Low water flow
  • Pump cycling on and off
  • Overheating and shutting down
  • Excessive noise or vibration

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

Before you buy β€” quick checklist

  • Verify your existing pump's voltage matches 230V
  • Check horsepower rating on old pump label
  • Measure plumbing union size for compatibility
  • Confirm 56Y frame size will fit your equipment pad
  • Ensure electrical supply can handle 12A draw
  • Take photo of existing wiring connections

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

Install difficulty: Medium β€” Some experience neededTypically 60-90 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 β†’

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 β€” 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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