The short answer for this family
The order below is this family's own, and it is not the order the brand-generic article sets out. The first checks below need no tools and no panel off, and they remove most of this list between them.
What the owner sees
- Frost builds as a sheet on the back wall — A sheet rather than the usual light dusting is an airflow story.
- The display looks normal and nothing runs — Power present and no compressor is a different problem from a compressor that runs and fails.
- The back of the unit is hot to the hand — Heat that cannot leave the coil is heat that comes back inside.
- One compartment holds and the other does not — Cold being made but not moved looks exactly like this.
- More than one QX unit shows the same thing — With 3 builds under this key, the same behaviour across two of them points at the family rather than at one machine.
- NEAR MISS — only the ice has stopped — Ice can stop for reasons that have nothing to do with cabinet temperature; that is the ice page.
Causes, most likely first on the QX family
- A defrost cycle that has stopped running — It is where this family starts. The unit works normally for a while after a manual thaw, which is the clearest evidence of this cause.
- A frosted evaporator blocking the air path — Second on this family. It is the cause most often mistaken for a dead compressor, because both leave a cabinet warm and a machine running.
- A failed evaporator fan motor — Third. Cold is made and then not delivered, so one compartment holds while the other drifts.
- A sealed-system leak or a failed compressor — Ranked last. It is the least likely cause on this list and the only one that cannot be checked from outside.
- Body: The brand-generic article on this symptom opens on a frosted evaporator blocking the air path. Here it does not: a defrost cycle that has stopped running has moved above it, and a frosted evaporator blocking the air path has moved down the list.
Check in this order, and why
- Note whether the frost returns on a schedule after a manual thaw — A cycle that has stopped running leaves a little more ice behind each time.
- Empty the unit, leave it open for a day and watch it recover — A unit that comes back after a thaw has named its own cause.
- Listen for the evaporator fan with the door switch held closed — No fan with a clean evaporator separates the two likeliest causes before a tool comes out.
- Look for oil traces at the compressor — Oil outside the tubing means the system is open and the checks above no longer apply.
- Body: The QX members share a layout, so this order holds across the ladder; what changes with size is how long each check takes, not which check comes first.
Before any panel comes off
Safety
Before a panel comes off, isolate the unit at the plug or at the breaker. A capacitor can hold a charge after the power is off. Do not tape or bridge the door switch to keep a fan running while you look. An interlock that is defeated is a blade that turns while a hand is in the cabinet. Refrigerant work is licensed work: nothing on the sealed side of this machine is owner work, whatever the symptom looks like from the front.
Models in the QX family
Reference| Model number | Family key |
|---|---|
| QX20 | alpicool:refrigerator:qx |
| QX30 | alpicool:refrigerator:qx |
| QX40 | alpicool:refrigerator:qx |
When to call a technician
On this family the split is simple: anything reachable without removing a panel is owner work, and nothing past that is. Work down the checks above first; they cost minutes and they remove most of this list. Call once they have all come back clean, because what is left is a sealed-system leak or a failed compressor, and that is the one cause here with no owner-side check at all. Call straight away, without working down the list, if you smell burning or see oil outside the tubing at the back: oil outside the tubing means the system is open, and every hour it runs after that costs more to put right.
