What this means on these models
On the Criterion EM microwave family an electrical symptom is the one class of fault where the right first action is not a diagnosis: unplug the oven and stop using it. A microwave holds a high-voltage capacitor that can retain a lethal charge after the power is off, so everything past the outlet is a technician job. Written against the one model the spine lists.
What this looks like on this platform
- Sparking or arcing inside the cavity — Stop the cycle and unplug it. Arcing is usually metal in the cavity or a damaged waveguide cover, and every extra second of it damages the oven further.
- Lights dim noticeably whenever the oven runs — A countertop oven sharing a circuit with other kitchen loads, or running on an extension lead, will do this and should be moved to its own outlet.
- A burning, acrid or ozone smell — Unplug it. That smell comes from arcing or from something overheating inside, and neither is something to keep testing.
- NEAR MISS: the oven simply will not start — A refusal with no smell, no spark and no trip is a door or lock fault rather than an electrical one. Read the page for an oven that will not start.
What it usually turns out to be here
- Metal or foil in the cavity, or a damaged waveguide cover — First because it is the most common and the most preventable: foil, a metal-trimmed dish, or a carbonised waveguide cover all arc. The cover is a consumable part and it is the one to look at after any arcing.
- The circuit is shared, extended or undersized — Second: a microwave on an extension lead or sharing a circuit with another heavy load trips breakers and overheats connections without anything inside the oven being faulty.
- The cord, plug or outlet is damaged or loose — A hot or discoloured plug is a failing connection, and it is a fire risk in its own right. This is checked before anything inside the appliance because it is visible and common.
- A high-voltage component has failed short — A breaker that trips the moment cooking starts points here: the transformer, diode or capacitor has failed in a way that loads the circuit. It is not an owner part and not an owner diagnosis.
What to check first, and why in this order
- Unplug the oven before anything else — This is the only diagnostic page here that starts with stopping. Arcing, tripping, shocks and burning smells all justify pulling the plug first and thinking afterwards. Each step rules out a cause the next one would inherit.
- Look into the cavity for metal and for burn marks — Foil, a metal-trimmed plate, or a burnt patch on the waveguide cover in the cavity wall. Most arcing is answered at this step.
- Check the plug, the cord and the outlet — Warmth, discolouration or a loose fit at the outlet is a failing connection. Do not keep using the outlet while you decide.
Safety first
Safety
Unplug the oven at the first sign of arcing, a burning smell, a shock or a repeated breaker trip, and leave it unplugged. Do not remove the outer case: the high-voltage capacitor can retain a lethal charge long after the oven is disconnected, and discharging it is a trade procedure. Never run a microwave empty, never put metal or foil in the cavity, and never run one on an extension lead. A standard household branch circuit is rated 15 A or 20 A, and a breaker that trips again is reporting a fault rather than being a nuisance.
Models in the EM family
Reference| Model number | Family key |
|---|---|
| EM044K-P00A0A | criterion:microwave:em |
When to call a technician
Where the line falls here is worth stating plainly. Looking in the cavity, checking the plug and outlet and sorting out what shares the circuit are owner work. Everything else here is a call, and in several of these cases it is an electrician rather than an appliance technician: a hot outlet, a tingle from the case or a breaker that trips with other appliances too are wiring questions. On this platform the case stays on: the capacitor inside can hold a lethal charge even unplugged, which is what makes this a trade job rather than a home one.
The rest of this family
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Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
