Skip to content
Free Shipping $49+
Factory Direct No Middleman
30-Day Returns
24/7 1-800-HEIMA-00
Track Order Install Videos FAQ Contact
Heima
Account
Cart
Shop All Parts Repair Guides Install Videos Brands About FAQ Contact ⚡ Clearance
Home/Appliance Parts/Thermostat & Thermal Fuse/KSD301A-A
KSD301A-A Bimetal Snap Disc Thermostat Compatible with Microwave Oven Dryer Coffee Maker, Replaces KSD301 KSD302 KI31
  • KSD301A A 01
  • KSD301A A 02
  • KSD301A A 03
  • KSD301A A 04
Factory Certified
Free Ship $49+
30-Day Returns
1-Year Warranty
Compatible Brands
Compatible Models
Showing 73 compatible models
Aftermarket Replacement · Factory Direct
OEM-compatible part built to original specifications. Not manufactured by or affiliated with the original equipment brand.

KSD301A-A Bimetal Snap Disc Thermostat Compatible with Microwave Oven Dryer Coffee Maker, Replaces KSD301 KSD302 KI31

SKU: KSD301A-A
Order within --:-- to ship today
Repair Time15-30 Minutes
DifficultyModerate
DIY FriendlyYes
Tools Needed
MultimeterPhillips ScrewdriverFlathead ScrewdriverNeedle-Nose PliersCamera or Phone (to document wiring)
Qty
Ships from China · 10–20 business days
No sales tax outside CA
or
KSD301A-A Bimetal Snap Disc Thermostat Compatible with Microwave Oven Dryer Coffee Maker, Replaces KSD301 KSD302 KI31
In Stock

This Part Fixes These Problems

No Heat

Appliance runs (drum spins, fan operates, magnetron cycles) but produces no heat — defective thermostat has failed open and broken the heating circuit.

Shuts Off Mid-Cycle

Unit stops heating or shuts down partway through a cycle and only restarts after cooling; indicates the thermostat is tripping prematurely due to fatigue or mis-calibration.

Overheating Protection Failure

Appliance overheats without shutting off, suggesting the thermostat contacts are stuck closed and no longer opening at the rated trip temperature.

Intermittent Heating

Heat cuts in and out randomly during operation; caused by a worn bimetal disc with inconsistent snap-action response.

Repair Guides

How to Replace KSD301A-A Bimetal Snap Disc Thermostat on Dryers & Microwaves — Step-by-Step
May 26, 2026
Universal Bimetal Thermostat Parts — Multi-Brand Appliance Compatibility
May 24, 2026
OEM vs Aftermarket KSD301A-A Thermostat: Honest Comparison for Multi-Brand Appliances
May 23, 2026

Product Description

Why Choose Our KSD301A-A Bimetal Snap Disc Thermostat?

🔧
Built to OEM SpecificationsRated 250V AC / 10A and 125V AC / 16A (resistive load), matching original factory electrical specs. Contact resistance ≤50 mΩ, insulation resistance 100 MΩ.
🌡️
Precise Temperature ActionNormally Closed (NC) snap-disc design opens circuit at rated trip temperature and auto-resets when cooled — no manual intervention required under standard operation.
🔁
100,000-Cycle Contact LifeBimetal snap disc rated for 100,000+ action cycles. Electrical strength: AC 50Hz 2000V/min with no breakdown or arc phenomenon — long-lasting and dependable.
🏠
Wide Appliance CompatibilityUsed in microwave ovens, dryers, coffee makers, water heaters, dishwashers, air fryers, electric ovens, toasters, refrigerators, and water dispensers.
📐
Standard 1/2-Inch Disc Form FactorBody size 33×12 mm with 6.35 mm (0.25 inch) spade terminals. Movable mounting flange for easy drop-in replacement of KSD301, KSD302, KI31, KSD201, 1NT, TK24/36T, US-118, and T11 series.
🛡️
Bakelite / Ceramic HousingHigh-temperature resistant Bakelite or ceramic shell withstands harsh thermal environments. Single-pole single-throw (SPST) structure under resistive load — safe and stable.

💡 Pro Tip: How to Diagnose a Faulty KSD301A-A Thermostat

Your part is likely the culprit if you notice any of the following:

⚠️ Appliance runs but produces no heat (dryer tumbles, microwave runs, but no warmth)

⚠️ Appliance shuts off mid-cycle and will not restart until fully cooled

⚠️ Coffee maker or water heater stops heating after a few minutes

⚠️ Multimeter continuity test shows open circuit on the thermostat at room temperature (should be closed/NC at room temp)

Set your multimeter to continuity or resistance mode. At room temperature, a good NC KSD301A-A reads near-zero ohms (closed). If you read OL/open at ambient temperature, the thermostat has failed and must be replaced. Always disconnect power before testing.

📦 What's in the Box

✅ 1× KSD301A-A Snap Disc Bimetal Thermostat (NC, 250V/10A, 33×12 mm, 6.35 mm spade terminals)

Questions & Answers

What does the '-A' suffix mean in KSD301A-A?
Answered by Support Team  ·  Mar 15, 2024
The '-A' suffix in the KSD301 series typically indicates the terminal orientation — specifically 0-degree (flat/straight) spade terminals. Always confirm the terminal style matches your original part before ordering, as other orientations (such as 90-degree bent terminals) also exist in the KSD301 family.
Is this thermostat normally open (NO) or normally closed (NC)?
Answered by Support Team  ·  Nov 20, 2023
The KSD301A-A is a Normally Closed (NC) thermostat. At room temperature, the contacts are closed (circuit is complete). When the temperature reaches the rated trip point, the bimetal disc snaps and opens the circuit, cutting power. It automatically resets (closes again) once the temperature drops back to the reset threshold.
Can I use this to replace the thermostat in my microwave oven?
Answered by Support Team  ·  Jan 8, 2025
Yes. The KSD301A-A is widely used in microwave ovens as a magnetron or cavity over-temperature protector. You must match the trip temperature of your original thermostat (printed on the component's label, e.g., 120°C or 150°C). Do not substitute a different temperature rating — using a thermostat with too high a trip temperature can create a fire hazard.
How do I test if my KSD301A-A thermostat has failed?
Answered by Support Team  ·  Jul 22, 2024
Set a multimeter to continuity or resistance (Ω) mode. At room temperature, probe both terminals — a good NC KSD301A-A should show near-zero resistance (circuit closed). If the meter reads OL or 'open' at ambient temperature, the thermostat has failed and needs replacement. Always unplug the appliance before testing.
What appliances use the KSD301A-A thermostat?
Answered by Support Team  ·  Feb 10, 2026
The KSD301 series is one of the most widely used thermal protection components in household appliances. It is commonly found in microwave ovens, clothes dryers, coffee makers, water heaters, dishwashers, electric ovens, toasters, air fryers, water dispensers, refrigerators, and electric irons. If your appliance uses a 1/2-inch snap-disc bimetal thermostat, the KSD301A-A is very likely compatible — just confirm the trip temperature and NC/NO type.

We typically respond within 1 business day. Include your appliance model number for the fastest answer.




    Customer Reviews

    Reviews

    There are no reviews yet.

    Be the first to review "KSD301A-A" Cancel reply

    Your email address will not be published. Required fields are marked *

    Related Parts

    40113801 High Limit Thermal Fuse Compatible with Whirlpool Maytag Amana, Replaces WP40113801 AP6009129 14218937 62600 915698
    40113801
    40113801 High Limit Thermal Fuse Compatible with Whirlpool Maytag Amana, Replaces WP40113801 AP6009129 14218937 62600 915698
    $10.99 Original price was: $10.99.$9.99Current price is: $9.99.
    279973 High Limit Thermostat & Thermal Cut-Off Kit Compatible with Whirlpool Maytag Kenmore KitchenAid, Replaces AP3094323 3391913 8318314 279973VP
    279973
    279973 High Limit Thermostat & Thermal Cut-Off Kit Compatible with Whirlpool Maytag Kenmore KitchenAid, Replaces AP3094323 3391913 8318314 279973VP
    $39.99 Original price was: $39.99.$28.99Current price is: $28.99.
    3392519 Dryer Thermal Fuse Compatible with Whirlpool Maytag Kenmore KitchenAid Roper, Replaces WP3392519 AP6008325 3388651 694511 80005
    3392519
    3392519 Dryer Thermal Fuse Compatible with Whirlpool Maytag Kenmore KitchenAid Roper, Replaces WP3392519 AP6008325 3388651 694511 80005
    134587700 Dryer Control Thermistor Compatible with Frigidaire Electrolux Kenmore Crosley, Replaces AP3866842 PS1149368 1156925 134216500
    134587700
    134587700 Dryer Control Thermistor Compatible with Frigidaire Electrolux Kenmore Crosley, Replaces AP3866842 PS1149368 1156925 134216500
    $51.99 Original price was: $51.99.$34.99Current price is: $34.99.

    Disclaimer: Compatibility information, part numbers, and model fitment data on this page are sourced from manufacturer databases and third-party references. While we strive for accuracy, please verify your appliance model number before ordering. Heima is not responsible for errors or omissions in compatibility listings.

    Home / Appliance Parts / Thermostat & Thermal Fuse / KSD301A-A Bimetal Snap Disc Thermostat Compatible with Microwave Oven Dryer Coffee Maker, Replaces KSD301 KSD302 KI31
    H
    heima

    Heima manufactures appliance parts in our own facilities and ships direct — no distributor, no markup. 200+ brands, 1.8M+ parts, 500K+ satisfied customers.

    Shop Parts
    Refrigerator Washer & Dryer Oven & Range Dishwasher AC & HVAC All Categories
    Support
    Find Your Model Number Installation Videos Live Chat Track My Order Start a Return FAQ
    Company
    About Heima Our Factory Quality Standards Return Policy Privacy Policy Contact Us
    © 2025 Heima Parts  ·  Factory Direct Appliance Parts  ·  All Rights Reserved
    VISA MC AMEX PayPal Discover