A Samsung double convection oven with a built-in microwave is a convenient high-end appliance, but when the microwave portion starts emitting smoke or suddenly stops heating, many homeowners immediately assume the worst.
Most people think the problem must be the magnetron, high-voltage diode, or another expensive microwave component. Sometimes that is true. But not always.
At Appliances Fix & Care LLC, we recently diagnosed a Samsung double oven microwave combo where the microwave portion had smoke coming from the unit and then stopped heating. The oven section still worked. The display worked. The buttons worked. The appliance still had power. But the microwave would no longer heat food.
The actual cause was not the magnetron. It was a damaged relay on the microwave control board.
Samsung’s own troubleshooting for a microwave that does not heat includes checking simple causes such as Demo Mode, Kitchen Timer use, door closure, and clearance/ventilation before requesting service. But when there is smoke, burning smell, or visible board damage, the appliance should be inspected by a qualified technician.
Samsung Double Oven Microwave Combo: What Happened?
In this case, the customer had a Samsung double convection oven unit with a built-in microwave. The microwave portion started producing smoke and then stopped heating.
The important detail was this:
The microwave still appeared to operate, but it did not actually heat.
That means a technician should not automatically jump to one conclusion. A microwave that runs but does not heat can have several possible causes, including a high-voltage diode, magnetron, capacitor, transformer, door switch, thermostat, wiring issue, or control board problem. RepairClinic also notes that microwaves can store dangerous high voltage even after being unplugged, so internal microwave diagnosis should be handled by a trained technician.
In this Samsung unit, the problem was found on the control board relay for the microwave circuit.
The Real Cause: Weak Relay Connection on the Control Board
After a careful inspection, the technician found that the relay on the microwave control board had been installed or seated weakly. Over time, heat and electrical load affected the relay connection.
As the relay overheated, the relay legs became damaged and eventually broke. Once that happened, the microwave stopped sending proper power through the circuit needed for heating.
The result:
- Microwave portion stopped heating
- Smoke appeared from the unit
- Oven section still worked
- Display and controls still worked
- The appliance looked “alive,” but the microwave had no heating function
This is why a proper diagnosis is so important.
Why This Is Often Misdiagnosed as a Bad Magnetron
When a microwave runs but does not heat, many people immediately think:
- Bad magnetron
- Bad high-voltage diode
- Bad capacitor
- Bad transformer
Those parts can absolutely fail. But they are not the only possible cause.
In a Samsung wall oven microwave combo, the control board and relay circuit should also be inspected carefully. If a relay is burned, loose, cracked, or damaged at the solder joints, the microwave may stop heating even if the magnetron itself is still good.
A quick diagnosis can easily become expensive if the technician replaces high-voltage parts without checking the board first.
Why the Control Board Must Be Inspected Carefully
The control board is the brain of the appliance. It sends power to different components at the right time. In a Samsung double oven microwave combo, the board may control or communicate with:
- Microwave heating circuit
- Relays
- Cooling fan
- Display panel
- Door switch circuit
- Oven functions
- Safety circuits
If the relay connection is weak, damaged, or overheated, the board may fail to deliver power properly to the microwave heating system.
Signs of a possible board or relay issue may include:
- Microwave stopped heating
- Burning smell
- Smoke from the unit
- Visible burn marks on the board
- Loose relay
- Cracked solder joints
- Melted connector
- Clicking sound but no heat
- Oven works, but microwave does not
In these cases, replacing the magnetron without checking the control board can be the wrong repair.
Can the Relay Be Replaced Instead of Replacing the Whole Board?
In some cases, yes.
If the damage is limited to the relay and the board is otherwise in good condition, a technician may be able to desolder the damaged relay and solder in a new relay. This can sometimes save the customer money compared to replacing a full control board or multiple high-voltage components.
However, this depends on the condition of the board.
Relay repair may be possible if:
- The board is not badly burned
- Traces are not destroyed
- The relay is available and matches the proper specifications
- No other components were damaged
- The wiring harness and connectors are still safe
- The technician is qualified to perform board-level repair
Sometimes the control board is too damaged and must be replaced. But the important point is this:
The control board should be checked before assuming the magnetron or diode is bad.
Samsung Microwave Smoking: Stop Using the Appliance
If your Samsung microwave or Samsung double oven microwave combo starts smoking, stop using it immediately.
Do not keep testing it repeatedly. Smoke can indicate overheating, electrical damage, a failing component, or a burned connection.
Before using the appliance again, it should be inspected by a professional technician.
Important safety note: microwave units can contain high-voltage components, including capacitors, that may store dangerous voltage even after the appliance is unplugged. Internal microwave repair is not a safe DIY job.
Common Causes of Samsung Microwave Not Heating
A Samsung microwave that does not heat may be caused by:
- Demo Mode
- Kitchen Timer mode accidentally used instead of cooking mode
- Door not closing properly
- Poor ventilation or clearance
- Door switch problem
- High-voltage diode failure
- Magnetron failure
- High-voltage capacitor issue
- Transformer issue
- Thermostat or thermal fuse problem
- Wiring issue
- Control board relay failure
Samsung support notes that Demo Mode, Kitchen Timer use, door closure, and clearance/ventilation should be checked when a Samsung microwave does not heat or appears to run without warming food.
But if there is smoke or a burning smell, the appliance needs professional diagnosis.
Why Board-Level Diagnosis Can Save Money
Replacing a magnetron, diode, capacitor, or full control board can become expensive. But if the actual failure is a damaged relay or weak solder connection on the control board, a more targeted repair may be possible.
That is why Appliances Fix & Care LLC focuses on diagnosis before replacing parts.
A good technician should:
- Inspect the control board
- Look for burned relay contacts
- Check solder joints
- Inspect wiring and connectors
- Confirm whether the microwave high-voltage circuit is receiving power
- Verify whether the magnetron, diode, and capacitor are actually defective
- Avoid unnecessary part replacement when possible
This approach can help reduce repair cost and avoid replacing good parts.
Samsung Double Oven Microwave Repair in Tampa, FL
At Appliances Fix & Care LLC, we provide professional Samsung double oven microwave combo repair in Tampa, FL.
We service:
- Samsung built-in microwave oven combos
- Samsung double convection ovens
- Samsung wall oven microwave combinations
- Samsung microwaves not heating
- Samsung ovens with smoke or burning smell
- Samsung microwave control board problems
- Samsung relay issues
- Samsung oven and microwave combo electrical problems
- Samsung built-in appliance diagnosis
If your Samsung microwave portion stopped heating but the oven still works, the problem may not always be the magnetron. The control board, relay, wiring, and safety circuits should be inspected carefully.
Samsung Microwave Not Heating in Tampa? Call Appliances Fix & Care LLC
If your Samsung double oven microwave combo is smoking, not heating, or showing signs of electrical failure, schedule professional service.
Appliances Fix & Care LLC provides reliable appliance repair in Tampa, FL and nearby areas, including:
- South Tampa
- West Tampa
- Carrollwood
- Brandon
- Riverview
- Lutz
- Wesley Chapel
- Citrus Park
- Westchase
- Town ’N’ Country
- Clearwater
- St. Petersburg
- Palm Harbor
We help homeowners diagnose appliance problems correctly and avoid unnecessary repairs whenever possible.
FAQ
Why is my Samsung microwave smoking?
A Samsung microwave may smoke because of food residue, overheating, poor ventilation, damaged wiring, a burned relay, a control board problem, or a failing high-voltage component. If there is smoke or a burning smell, stop using the appliance and schedule professional service.
Why is my Samsung microwave running but not heating?
A Samsung microwave may run without heating because of Demo Mode, Kitchen Timer mode, door switch problems, magnetron failure, diode failure, capacitor issues, thermostat problems, wiring problems, or control board relay failure.
Can a bad relay cause a Samsung microwave not to heat?
Yes. If the relay on the control board is damaged, loose, burned, or has broken solder connections, it may prevent the microwave heating circuit from operating correctly.
Does a Samsung microwave not heating always mean the magnetron is bad?
No. A bad magnetron is one possible cause, but it is not the only one. A technician should also check the diode, capacitor, door switches, thermostat, wiring, control board, and relay circuit.
Can the control board relay be repaired?
In some cases, yes. If the board is not severely damaged, the relay may be desoldered and replaced. However, if the board is burned or the circuit traces are damaged, the full board may need replacement.
Do you repair Samsung double oven microwave combos in Tampa, FL?
Yes. Appliances Fix & Care LLC provides Samsung double oven microwave combo repair, Samsung wall oven microwave repair, and Samsung built-in microwave diagnosis in Tampa, FL and nearby areas.