LG [dH] fault codewhat it means and how to fix it

dH is the defrost resistance issue, and LG are unusually precise about what the appliance measured before deciding something was wrong. Their published wording is that the temperature measured by the defrost sensor has not increased by more than five degrees Celsius within eighty minutes of the start of defrosting, and that the evaporator may be blocked by ice. Understanding that test tells you exactly what has happened. Every frost-free appliance periodically runs a heater across the evaporator to melt off the frost that has collected there. The control board expects to see the temperature climb as that heater works.

When it starts a defrost, waits eighty minutes and sees the temperature barely move, it concludes the heat is not arriving and stops trusting the cycle. LG name the things that produce that reading: ice accumulation, a blocked drainage hole, a disconnected temperature fuse, a disconnected heater, or a main PCB failure, and in the analog section of their code list they add that the heating relays may be malfunctioning and the drain may be clogged. Of those only the ice and the blocked drain are owner territory, and LG say so in two ways. Their master code list puts dH under the blanket instruction to request service. Their per-code articles for F dH, r dH and Er dH then publish the owner’s part: if the drain hole is blocked with ice so that meltwater cannot reach the drain tray, disconnect the power, open the compartment door wide, and wait one day in summer or three days in winter for the ice to melt, after which water should run out to the drain tray normally. Their 2026 troubleshooting article gives a shorter version of the same thing — remove the food, put dry towels on the floor in front of the doors, unplug, and leave the doors open for at least twelve hours — and precedes it with a reset: unplug, wait about five minutes, plug back in.

All three articles end the same way: if the same code is repeated, it needs an LG service technician for an accurate diagnosis, because the appliance may operate normally once the ice is removed but the error can return over time. So the honest shape of this code is a manual defrost that buys time, and a heater, fuse, relay or board repair if it comes back. What you will notice as an owner is the consequence rather than the cause: a freezer that still freezes while the fridge above it gets steadily warmer, sometimes with a rattling noise as the fan starts to catch on ice. Remember that the prefix does not matter on LG appliances: dH, F dH, r dH, Er dH, FdH and dHF are all this code. LG say their most common errors may be preceded by the letters E, r or Er; the one thing the letter adds, in their per-code article, is that F means the freezer side and r the refrigerator side.

1. 1

   Reset it first, LG’s way: unplug from the wall socket, wait about five minutes, plug back in and see whether the code has cleared. LG’s 2026 article puts this before anything else.

2. 2

   If it returns, move the food to another fridge or freezer if you have one. LG say to have the appliance checked by a technician instead if you are worried about the food, because the defrost that follows is long.

3. 3

   Put dry towels on the floor in front of the doors, disconnect the power plug and open the compartment door wide. LG’s figures are one day in summer and three days in winter for the ice to melt, and at least twelve hours in their shorter 2026 version.

   Use time and open doors only. Do not chip at the ice or apply a hairdryer or hot water: the evaporator pipework behind the panel carries flammable refrigerant.
4. 4

   When the ice has melted completely, water should run out to the drain tray at the back. LG say that is the sign the drain is clear again. Plug back in and let it pull down.

5. 5

   If the same code comes back, book an engineer and tell them a manual defrost cleared it. LG’s instruction for a repeated code is a service technician, and the remaining causes — heater, fuse, relay or board — are inside the appliance.