20 Amp Slo Blo Fuse MDA20-FUSE

Name: 20 Amp Slo Blo Fuse MDA20-FUSE
Brand: Allied Innovations
SKU: MDA20-FUSE
Price: 2.39 USD
Availability: InStock

Part #: MDA20-FUSE

$2.39

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About this fuse

The Allied Innovations MDA20-FUSE is a 20 amp slow-blow ceramic fuse designed for spa electrical systems requiring reliable overcurrent protection. This 250VAC-rated fuse features time-delay characteristics that prevent nuisance tripping from normal motor startup surges while providing essential protection against sustained overloads and short circuits. The ceramic construction ensures superior heat dissipation and arc suppression compared to glass alternatives.

When your spa's control system needs dependable electrical protection, this OEM-quality fuse delivers exact fit guaranteed performance with our same-day shipping and comprehensive 1-year warranty. The slow-blow design makes it ideal for motor circuits and heating elements that draw higher inrush currents during startup. Always verify amperage requirements match your spa's electrical specifications before installation, and ensure power is completely disconnected before replacing any electrical components.

Exact part number

MDA20-FUSE

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Also known as / Replaces

This part replaces or is interchangeable with:

20 Amp Time-Delay Fuse
20A Slo-Blo Fuse
MDA20
Slow-Blow Ceramic Fuse 20A

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

Technical specifications

Voltage: 250VAC
Amperage: 20A

Common symptoms this part fixes

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

Spa completely dead with no power to control board
Control system resets or shuts down under normal load
Motor or heater circuit not receiving power
Nuisance tripping on startup replaced with stable protection
Board-level fuse blown after surge or overload event

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

Before you buy — quick checklist

Confirm the blown fuse is rated 20A — check the existing fuse or control board silkscreen label before ordering
Verify slow-blow (time-delay) type is required — do not substitute a fast-blow fuse in a motor or heater circuit
Check the fuse body size matches MDA series (5x20mm glass tube equivalent in ceramic) before purchasing
Always disconnect all power at the breaker before inspecting or replacing fuses
Inspect the circuit for the underlying fault that caused the fuse to blow — replacing the fuse without resolving the root cause will result in repeat failure

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

Easy — DIY-friendlyTypically 5-15 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.

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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.

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