---
title: "Combination microwave hums but does not heat"
description: "A built-in combination cavity that lights up, turns and does nothing to the food. It splits into two questions quickly because the convection side and the microwave side fail independently:"
url: "https://askomiami.support/symptoms/microwave-hums-no-heat/"
date_modified: "2026-09-13"
Appliance type: "Microwaves"
---


# Asko combination microwave hums but does not heat

### What to do in the next ten minutes

Put a cup of water in and run the microwave function for sixty seconds. Hot means that half works. Then try a convection program and see whether the cavity warms. Note which of the two failed. And check the door: if it needs a firmer push than it used to, or has visible play at the top corner, say so — that changes the urgency.

### Why the interlocks come before the magnetron

Three switches, in series, operated every time the door closes. They wear, they are inexpensive, and when one stops confirming the cavity stops dead with no warning and no indication of which one it was. Testing them one at a time is most of the labor on this repair and it is the right order of work, because the alternative is an expensive component fitted on suspicion.

### Replacing it is a joinery question

These are fitted into a cabinet cut to their dimensions, so the replacement that fits that opening is not a shelf item. That is why a repair on a built-in combination cavity is usually worth doing where the same repair on a countertop machine would not be, and we give that arithmetic at the diagnostic.

A door interlock has failed

Three safety switches in series behind the latch, all of which must agree before the cavity will run. They are wear parts and by a distance the most common cause.

The magnetron circuit

The expensive answer on the microwave side, and it is reached after the interlocks rather than before them.

The door has dropped on its hinges

The switches are fine and the geometry is not. A switch replaced under a dropped door is replaced again within the year.

Does convection still heat?

One minute, and it decides the entire direction of the visit.

Does the door need a push?

Take that seriously in its own right. A microwave door is shielding, not a lid.

What exactly does the display show?

If it is ERROR and two digits, nothing published decodes them — but the digits and the model are still worth recording.

The cavity runs and nothing gets warm

What it usually means

A cup of water for sixty seconds splits the diagnosis in half

Three door interlocks in series — one out of agreement stops everything

ERROR XX is undecoded in four manuals, so the split is made at the appliance

What to do in the next ten minutes

Put a cup of water in and run the microwave function for sixty seconds. Hot means that half works. Then try a convection program and see whether the cavity warms. Note which of the two failed. And check the door: if it needs a firmer push than it used to, or has visible play at the top corner, say so — that changes the urgency.

Why the interlocks come before the magnetron

Three switches, in series, operated every time the door closes. They wear, they are inexpensive, and when one stops confirming the cavity stops dead with no warning and no indication of which one it was. Testing them one at a time is most of the labor on this repair and it is the right order of work, because the alternative is an expensive component fitted on suspicion.

Replacing it is a joinery question

These are fitted into a cabinet cut to their dimensions, so the replacement that fits that opening is not a shelf item. That is why a repair on a built-in combination cavity is usually worth doing where the same repair on a countertop machine would not be, and we give that arithmetic at the diagnostic.

### Is it safe to keep using?

If the door is sound and the machine simply will not heat, it is not dangerous — it is useless. If the door needs a push or has play in it, stop.

### The turntable turns but nothing happens.

That is normal for this failure. The turntable motor is independent of the magnetron, so a turning plate proves only that the machine has power.

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