Sparks behind the waveguide cover, a hum with no heat, or a unit that keeps running after you open the door: one call to Acdc Appliance Repair connects you with a licensed, insured independent microwave pro near Exeter who works on over-the-range, built-in and drawer models.
A microwave is not a toaster. Inside the cabinet sits a high-voltage capacitor that can hold a lethal charge long after the plug is pulled, which is why this repair belongs with a trained technician and never with a screwdriver and a video.
We run a free referral line for homeowners. A dispatcher hears what the microwave is doing and connects you with an independent local technician who knows both the high-voltage side and the installation side of these units.
Each pro we connect you with runs an independent shop with the license and insurance local rules call for. Asking for proof on arrival is perfectly normal.
A magnetron or control board for a built-in can be a real expense. The technician writes the quote before any work starts, so you can compare it to a replacement unit and decide.
We look for a pro already working near Exeter. A same-day slot opens up regularly when local pros have breathing room, and the arrival window gets set while you are on the line.
Expect an insulated discharge tool for the capacitor, a multimeter for diode and transformer checks, the model tech sheet, and a microwave survey meter to check for leakage after high-voltage work.
This is the work we route for OTR, wall-mounted, drawer and convection combo microwaves. Every job starts by safely bleeding the capacitor before a single meter lead goes in.
Everything seems to run except the heating. That points to the high-voltage circuit: a failed magnetron, a shorted diode, an open capacitor, or a burnt transformer winding. The pro checks each part with a meter after bleeding the stored charge.
Sparking inside the oven often traces to a food-soaked waveguide cover, bare metal where the cavity paint chipped, or a worn rack support in a combo unit. Ignoring it can scorch the cavity and kill the magnetron.
Microwaves use a chain of door interlock switches plus a monitor switch. When a switch sticks, the monitor switch shorts the line on purpose and blows the line fuse, so the whole unit goes dark. A unit that runs with the door open needs to be unplugged right away.
When keys stop responding or the oven refuses to shut off at zero, the touchpad membrane or a welded relay on the control board is usually behind it. The pro tests the keypad matrix and the relays first so the right part gets ordered.
An over-the-range microwave also works as the range hood. Grinding fans, a lamp that never turns on, greasy metal filters, and a spent charcoal filter on recirculating installs all get handled here.
A plate that will not spin usually needs a turntable motor or a new coupler. OTR units that sag or rattle may have a loose wall bracket or top bolts pulled through the cabinet, which is a safety issue with a hot stove below.
Use this as a quick read before you call. Share what you see with the dispatcher, and the technician can bring the most likely parts.
| Symptom | Common cause | What the tech checks |
|---|---|---|
| Runs, light on, no heat | Magnetron, diode, capacitor or transformer failure | Each high-voltage part with the capacitor discharged |
| Completely dead, no display | Blown line fuse from a failed door switch | Fuse, interlock switches, monitor switch |
| Sparks or smoke inside | Burnt waveguide cover, chipped cavity paint | Cover, cavity surface, stirrer, rack supports |
| Keeps running at zero or with door open | Welded relay or failed interlock | Control board relays and door switch chain |
| Plate will not turn | Turntable motor or coupler | Motor continuity, coupler, roller ring |
| Vent fan loud or dead | Fan motor bearings, greasy filters | Fan motor, damper, grease and charcoal filters |
Most pros will be honest that a small countertop unit is cheaper to replace than repair. Over-the-range, built-in, drawer and convection combo models are different: they are pricier, they are sized to a cabinet opening or wall plate, and replacing one can mean new trim, new brackets and reworked ductwork.
Unplug it, leave the cover on, and call. A dispatcher answers day and night.
Let the dispatcher know if the unit is over-the-range, built-in, a drawer or a combo, and describe the symptom. The model number is usually on a sticker inside the door opening, and having it speeds up parts.
An independent technician working close to Exeter gets the job, and the dispatcher shares the arrival window. Same-day arrivals are routine when a local independent pro is free.
First comes a safe discharge of the capacitor, then meter tests on the magnetron, diode, transformer, door switches and board. An OTR unit sometimes has to be lifted off its mounting plate. The written, upfront quote comes before any work begins, and you decide.
Once the part is in, the technician runs a water heating test and, if the high-voltage side was opened, checks the door edges with a leakage survey meter. The technician typically documents the parts and labor warranty on the work order; ask for a copy.
The OTR unit died with no display at all. The pro found the line fuse blown and a failed interlock switch behind it. He replaced the switch and the fuse together and explained that a fuse alone would have popped again within a week.
Our wall-mounted microwave ran with no heat. Replacing it meant matching a trim kit, so I asked about repair. She tested the high-voltage parts, swapped the magnetron, and ran a leakage check with a survey meter before packing up.
Blue sparks kept flashing inside the cavity. The technician pulled a waveguide cover that was charred from spatter, put in a new one, and told me how to wipe it down so it does not happen again.
The drawer microwave kept running even at zero, which scared us. The technician diagnosed a stuck relay on the control board, ordered the exact board, and installed it on a return visit.
When the light, fan and turntable all work but food stays cold, the high-voltage circuit has failed. The most common causes are a bad magnetron, a shorted diode, an open capacitor, or a burnt transformer. These parts carry lethal voltage, so let a trained technician test them.
Not until someone looks at it. Arcing tends to start at a greasy waveguide cover or a bare spot in the cavity paint, and it can take out the magnetron if it keeps happening. If it smokes, leave the door shut and unplug it if the cord is within safe reach.
Most of the time a dead microwave has blown its line fuse, and the fuse blew because a door switch failed and the monitor switch tripped it. A good pro replaces the failed switch along with the fuse, not just the fuse.
Frequently. Over-the-range and built-in units are expensive and fitted to the opening, so a new one brings its own installation costs. Small countertop models are usually better replaced. With a written quote from the pro in hand, you can make the call.
We strongly advise against it. That capacitor stores enough energy to kill, even with the plug pulled. Keep the outer case on and leave the discharge to a technician with proper insulated tools.
Ask for it, especially after high-voltage or door work. Many pros sweep the door seal and vents with a microwave survey meter before they leave, to confirm the unit is sealed properly.
We route microwave calls from houses, condos and apartments throughout Exeter and nearby neighborhoods. Dispatchers send each job to an independent pro already working close to your address, which helps when an OTR unit needs a second set of hands to lift off the wall plate.
Someone answers around the clock. Calls after hours are typically scheduled for the first slot next morning, while daytime calls can become same-day visits when a nearby pro has room.
