Whirlpool Microwave Not Heating? Magnetron W11578959 – Restore Full Heating Power Fast

A failed magnetron is the single most common cause of a microwave that runs but produces no heat — and it is the correct repair for Whirlpool, KitchenAid, and JennAir combo wall oven microwaves that hum, spin the turntable, but leave food completely cold. In these models, the magnetron is the core component that generates the microwave energy used to heat food. When it fails, the microwave appears to operate normally — the light comes on, the turntable spins, the timer counts down — but no heat is produced. ⚡ Common failure point in Whirlpool-built combo wall oven microwave units. Part W11578959 is the genuine OEM replacement that supersedes W11504545 and restores full microwave heating power immediately.

❓ Is This the Right Part?

This is the correct fix if ALL of the following are true:

• ✔ The microwave powers on — light, turntable, and display all function normally
• ✔ The door latch and interlock switches are confirmed working
• ✔ The high-voltage diode and capacitor have been tested and ruled out
• ✔ ONLY problem is the microwave runs but produces absolutely no heat

Not sure? Send us your model number — we’ll confirm before you order.

🔧 Common Symptoms

• Microwave runs a full cycle but food comes out completely cold
• Turntable spins and light works, but no heating occurs
• Microwave hums louder than normal during operation with no heat output
• Burning smell from the magnetron area followed by loss of heating
• Microwave trips the breaker or blows a fuse when attempting to heat

✔ If these symptoms match, this is the most likely failed component in the system.

✔ In most cases, replacing this magnetron restores full microwave heating power immediately.

📦 Part Details

• Part Number: W11578959
• Type: Microwave Magnetron — OEM Whirlpool replacement
• Replaces: W11504545
• Brands: Whirlpool, KitchenAid, JennAir, Maytag

⚙️ Installation

Skill Level: Advanced — 60–90 minutes. HIGH VOLTAGE HAZARD — professional installation strongly recommended. Unplug the microwave and discharge the high-voltage capacitor before any internal work. Remove the outer cabinet, locate the magnetron assembly, disconnect the wire harness and waveguide connections, remove the mounting hardware, and install W11578959 in reverse order. Restore power and run a 1-minute heat test with a cup of water to confirm full heating output.

✓ Compatible Models

Confirmed compatible with JMC2430LM00, JMW2427LL00, JMW2427LM00, JMW2430LL00/03, JMW2430LM00/03, JMW3430LL00/03, JMW3430LM00/03, KOCE500EBS23, KOCE500ESS20/22/23, KOCE500EWH20/22/23, KOCE507EBS20/22, KOCE507ESS20/21/22, KOCE507EWH20/22, KOCE900HBS20/22/23, KOCE900HSS20/22/23, KOEC527PBS00, KOEC527PSS00, KOEC530PBS00, KOEC530PPS00, KOEC530PSS00, KOEC530PWH00, MMW9730FZ20, MOEC6030LZ01, WOC54EC0HB/HS/HW20, WOC54EC7HB/HS/HW20, WOC75EC0HS/HV20, WOC75EC7HS20/21/22, WOC75EC7HV20, WOEC3030LS01, WOEC5030LB/LW/LZ01, WOEC5930LZ01, WOEC7027PZ00, WOEC7030PV00/01, WOEC7030PZ00/01. Contact us to verify your model number before ordering.

💡 Pro Tip

✓ Model-Specific Repair Pages