---
title: "Heat dry system service"
description: "LG heat dry system service: lG's dishwashers dry with a heated air system and, on many models, a door that opens itself at the end of the cycle."
url: "https://lgmiami.support/services/heat-dry-system-service/"
date_modified: "2026-09-06"
Appliance type: "Dishwashers"
---


# LG heat dry system service

### Wet dishes that are not a repair at all

Three household things beat every part in this system. Rinse aid, which is not optional on a machine that dries with air rather than a glowing element — an empty reservoir shows up as water beaded over everything and glasses that spot. Plastic, which holds no heat and comes out wet in any dishwasher ever made. And the door that opens itself at the end of the cycle, which achieves nothing if the machine is unloaded the moment it beeps or if a towel is hung over the handle. Try all three for a week. If it still finishes wet and reports one of the drying codes, the visit is warranted.

What this involves

F31, F35 and F37 — fan, temperature, and the door actuator

The machine is entirely usable meanwhile, which is worth knowing

Rinse aid is checked first because it does much of the drying

Separate drying from washing

A wash that is unaffected narrows this to the drying system immediately.

Check the rinse aid

An empty reservoir produces poor drying on a machine with nothing wrong with it.

Read which of the three

F31, F35 and F37 are a fan, a sensor and an actuator, and they are not interchangeable.

Check the auto-open door is not obstructed

A bin, a mat or a cabinet handle opposite will stop it and produce F37.

Verify a full dry cycle

Including the plastics, which are the honest test.

### The door popping open at the end startled me. Is it supposed to do that?

Yes, on many of these models, and it is the drying. Let it stand open for half an hour before you unload and the difference is obvious.

### Can the auto-open be turned off?

On some models it can, and we would rather you did not — it is doing most of the drying work. If it is opening into a cabinet handle or a countertop overhang, tell us, because that is a fitting problem with a real solution.

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**[Read full article: Heat dry system service](https://lgmiami.support/services/heat-dry-system-service/)**