Cooking
Microwave Repair for Over-the-Range and Built-In Models
A built-in microwave that runs without heating is usually worth a look. A countertop model that fails often isn't. You'll know which situation you're in before any work starts.
Booking online works too. With the microwave's model number in the form, we can check part availability before we come.
First the appliance and its location, then your contact details. We follow up to schedule.
What happens when you press Start
The magnetron turns high voltage into microwave energy, which makes the water in food vibrate and heat up. Building that voltage takes a transformer, a high-voltage capacitor and a diode, or on inverter models an inverter board. The control runs everything through a set of door switches, all of which have to agree the door is shut.
Those door switches are also the most common failure. If they close out of sequence, a monitor switch deliberately blows the main fuse, and the microwave seems completely dead. Replacing the fuse without finding the switch problem just blows another one.
Over-the-range models add a vent fan, lights and a grease filter. Drawer microwaves add a motor and latch to open and close the drawer, and speed ovens add convection heating. Through all of it, the capacitor can hold a dangerous charge even when the unit is unplugged, which is why the outer case should stay closed.
- Over-the-range
- Built-in with trim kit
- Microwave drawer
- Speed and convection
- Countertop
- Inverter models
Microwave symptoms and likely causes
Most of these faults live inside the case, where high voltage is stored, so read this as a guide to what the technician will test rather than a to-do list.
- Runs and turns, but food stays cold
- Magnetron, high-voltage diode or capacitor, transformer, inverter board
- Completely dead, no display
- Main fuse blown by a door switch fault, thermal cutoff, control board
- Sparks or arcing inside
- Metal in the cavity, damaged waveguide cover, built-up food splatter, chipped cavity paint
- Stops partway through cooking
- Door switch, thermal cutoff, magnetron overheating, blocked vent
- Turntable won't turn
- Turntable motor, coupler, roller ring out of place
- Loud buzz or hum
- Magnetron, transformer, fan motor rubbing
- Vent fan or light out (over-the-range)
- Fan motor, bulb or socket, switch or control relay
Safe checks you can make
- Heat a cup of water for one minute. If it comes out warm, the microwave is heating and the problem lies elsewhere; if not, the fault is inside the case.
- Open and close the door firmly, and look for a cracked latch hook or a door that sits crooked. A door that doesn't close cleanly is the usual reason a microwave won't start.
- Take out any metal, twist ties or foil, and wipe splatter off the ceiling and the waveguide cover, the small panel on the inside wall.
- Check the breaker, and the outlet the microwave plugs into. Over-the-range models are usually plugged in inside the cabinet above.
- Seat the turntable on its coupler and roller ring.
Before you touch anything: Never remove the outer case of a microwave. The high-voltage capacitor can hold a lethal charge even when it's unplugged. If there's arcing, smoke or a burning smell, stop using it, unplug it, and leave it closed.
When a microwave needs a technician
- It runs but doesn't heat.
- It went dead suddenly, especially right after the door was closed.
- Sparks continue after the metal is out and the cavity is clean.
- The vent fan on an over-the-range model stops or grinds.
- The door is damaged or won't latch.
How a microwave repair visit works
The technician discharges the capacitor before any testing, then checks the door switches, fuse, diode, capacitor, magnetron and transformer or inverter. Over-the-range models are often tested in place, though some have to come off the wall, which needs a clear counter underneath.
You'll hear what failed and whether it's worth fixing, then get a quote. Nothing is repaired until you approve. Parts are matched to the model number.
Repair or replace the microwave?
For most countertop microwaves, a magnetron or control board failure is reason enough to replace, and we'll say so. Door switch and fuse repairs are inexpensive by comparison and can be worth it.
Over-the-range, drawer and built-in units are a different case. Replacing them means mounting, venting and matching a trim kit or cabinet opening, and some drawer models are expensive. For those, repair is usually the better choice unless the part has been discontinued.
Why Book Us for Microwave Repair
We say when it isn't worth it
Many microwaves cost less to replace than to repair, and you'll hear that before you spend money.
High voltage handled first
The capacitor is discharged before the case is opened, and then each high-voltage part is tested in turn.
Model-matched parts
Magnetrons, switches and boards are ordered to your model number, and we use the maker's parts when they can be had.
See the Maryland neighborhoods and ZIP codes we cover, or request a microwave repair.
Microwave Repair in Houses, Townhomes and Condos
Over-the-range microwaves are standard in many of the townhouses and condos around Silver Spring, Bethesda and College Park, where they double as the range hood. Renovated kitchens in Chevy Chase and Potomac often have a microwave drawer below the counter or a speed oven built into a column. Countertop units usually aren't worth repairing; built-in ones usually are, since replacing them means mounting, venting and trim.
How a Microwave Repair Visit Works
Book the Visit
Say what kind it is (countertop, over-the-range, built-in or drawer) and whether it runs without heating, sparks or is dead.
Find the Fault
The high-voltage section is discharged safely before testing. Then the magnetron, diode, fuses, door switches and board are checked.
Approve the Price
On inexpensive countertop units we'll tell you if replacing beats repairing. Otherwise you get a price before we start.
Fix and Check
We heat a cup of water to confirm the fix, and on over-the-range units check the vent fan and light as well.
Related Services
More appliances, brands and areas on this site.
Microwave problems we repair
The microwave faults we diagnose, from heating failures and dead controls to door, fan and turntable problems.
- Microwave Not Heating
- Sparking Inside
- Turntable Not Spinning
- Door Won't Close / Open
- Display Not Working
- Making Loud Noise
- Won't Start
- Sparking Inside Microwave
- Waveguide Cover Burned or Damaged
- Door Switch Failure
- Door Not Closing Properly
- Door Handle Broken
- Turntable Making Grinding Noise
- Control Panel Not Responding
- Runs with Door Open
- Noisy During Operation
- Cooling Fan Not Working
- Burns Food Too Quickly
- Microwave Won't Start
- Interior Light Not Working
- Over-Range Microwave Ventilation Poor
- Grease Filter Clogged
- Charcoal Filter Saturated
- Error Code Displayed
- Intermittent Heating
- Microwave Runs but No Magnetron Power
- Popping or Crackling Noise During Operation
- Overheating and Shutting Off
- Arcing from Metal Rack
- Fan Running After Microwave Is Off
- Some Display Digits Missing
- Sparking from Turntable Tray Area
- Food Heating Unevenly
- Clicking Sounds After Cooking
- Steam or Condensation Inside Microwave
- Burning Plastic Smell from Microwave
- Power Level Selection Not Working
- Inverter Board Failure (Inverter Microwaves)
- Interior Light Flickering
- Microwave Tripping Circuit Breaker
- Water or Moisture in Control Panel
- Error Code Indicating Thermal Fault
- Sensor Cooking Not Working Properly
- Child Lock Won't Disable
- Interior Cavity Coating Peeling
- Ventilation Fan Motor Failure (Over-Range)
- Arcing from Magnetron Antenna
- Runs Only a Few Seconds Then Stops
- Door Won't Latch Closed
- Runs at Wrong Power Level
- Keypad Buttons Sticking
- Vent Damper Stuck Closed or Open
- No Sound / No Beep
- Display Shows Wrong Time After Power Outage
- Grease Fire Risk — Heavy Grease Buildup
- Door Window Cracked
- Unusual Smell After Each Use
- Humidity Sensor Not Working (Sensor Cook)
- Door Seal / Gasket Damaged
- Convection Mode Not Baking Properly
Microwave brands we service
Notes on the microwave brands we hear about most, then all the brands we cover.
- GE Appliances microwave repair
- Whirlpool microwave repair
- Samsung microwave repair
- LG microwave repair
- Sharp microwave repair
- Bosch microwave repair
- KitchenAid microwave repair
- Frigidaire microwave repair
Where we repair microwaves
Each area page adds notes on the microwaves we see in its homes, plus its ZIP codes. Or book below.
More reading on microwaves
Microwave Repair Questions
The questions that come up most often. Anything not covered here, ask us when you call, or add it to the booking form's notes field.
Have a different question?
Tell us what make it is and what's going wrong. A few things can be settled over the phone, and anything else gets looked at during the visit.
It depends on the type. A countertop model usually isn't worth a major repair. An over-the-range, built-in or drawer microwave usually is, because replacing it involves installation and fitting the space. Door switch and fuse repairs are often worth doing on any type.
Most often a door switch failed and the monitor switch blew the main fuse to protect you. It can also be a thermal cutoff tripped by overheating or a blocked vent. Because the fix is in the high-voltage section, it's a job for a technician.
Not until you know why. Remove any metal, clean food off the ceiling and the waveguide cover, and try again with a cup of water. If it still sparks, stop using it. A burned cover or chipped cavity coating gets worse with use.
Yes, including Sharp and Bosch drawer models. On top of the usual heating parts, a drawer microwave has its own motor and latch system, and those are common repair points.
Many over-the-range models turn the fan on automatically when they sense heat from the cooktop below, and keep it running until the area cools. If it runs constantly with the range off, the sensor, a stuck relay on the control or the keypad may be at fault.