A Rochester homeowner called us in December about a GE GSH25JSTCSS side by side refrigerator. Frost kept building on the freezer back panel even though the unit ran normally, and it came back within days of a manual defrost. The fresh food section was also starting to run warm.
Quick answer: why does a GE refrigerator keep frosting up?
On this GE side by side, the defrost heater had burned open and the defrost thermostat no longer closed when cold, so the evaporator coil never defrosted. Frost built up until it blocked airflow. Replacing both parts fixed it. On other GE refrigerators the same symptom can come from a failed defrost control, a door switch that keeps the fan running with the door open, or a door that does not seal.
Why does a GE refrigerator build up heavy frost?
Heavy frost almost always means the automatic defrost system has stopped working or warm, humid air is getting in. Every frost free refrigerator melts the ice off its evaporator coil several times a day. When that cycle fails, frost blocks the airflow and the fridge slowly warms up.
- Failed defrost heater
- Failed defrost thermostat (bimetal)
- Faulty door switch that keeps the fan running with the door open
- Torn or warped door gasket
- Control board or sensor fault
How we diagnosed it
| What we tested | Result |
|---|---|
| Door gasket and alignment | Sealing evenly, no gaps |
| Door switch | Working. Fan stopped when the switch was pressed |
| Control diagnostic mode | No sensor fault codes |
| Defrost heater continuity | Open circuit, heater failed |
| Defrost thermostat | Not closing when cold, failed |
The repair
We replaced the defrost heater and the defrost thermostat together with genuine GE parts. They work as a pair, and when one fails from age the other is usually close behind. After the repair we forced a defrost cycle to confirm the heater warmed and the thermostat opened, then let the fridge pull down to temperature.
What you can do before a technician arrives
- 1
Move food to a cooler
Keep the doors closed as much as possible. A closed fridge holds safe temperature for about 4 hours.
- 2
Defrost by hand
Unplug the fridge, lay towels down and let the ice melt naturally. A garment steamer speeds it up. Never chip ice with a knife or screwdriver.
- 3
Check the gasket
Close the door on a dollar bill. If it slides out easily, the seal is not holding.
- 4
Book a repair if frost returns
A manual defrost only buys a few days. Returning frost means the defrost system needs testing.
How the defrost system works on a GE side by side
A frost free refrigerator does not stay frost free by magic. Every time the door opens, humid kitchen air enters and its moisture freezes onto the coldest surface, the evaporator coil behind the freezer back panel. Several times a day the control pauses cooling and powers a defrost heater mounted on the coil. The defrost thermostat, a small bimetal disc clipped to the coil, only lets current reach the heater while the coil is cold; once the frost melts and the coil warms, it opens and ends the cycle. The melt water runs down a drain tube to a pan near the compressor, where it evaporates.
If any part of that loop fails, frost keeps accumulating. At first you may only see a thin layer, then a thick white sheet across the panel, then ice around the fan shroud. Because the fan pushes air through the coil, a frosted coil means less cold air reaches the fresh food side, which is why this owner also noticed the fridge running warm.
Signs your GE has a defrost problem
- Frost or ice on the freezer back panel or around the vents
- The fresh food section slowly warms over several days while the freezer stays cold
- Frost comes back within days of a manual defrost
- A rattling or scraping noise as the fan blade touches ice
- Water pooling under the crisper drawers from a frozen drain
Other causes we rule out first
Door switch and fan
GE side by sides stop the evaporator fan when the freezer door opens. If the switch fails, the fan keeps pulling warm room air across the coil every time the door opens, which adds frost quickly. That is why we test the switch before condemning defrost parts.
Door gasket
A torn or flattened gasket lets warm air in all day. The dollar bill test catches most gasket problems: if the bill slides out with no drag, the seal is weak at that spot.
Defrost control or main board
Newer GE models use the main control to time defrost. If the heater and thermostat test good, the control may not be calling for defrost. Many GE models have a service test mode that forces a defrost cycle, which helps confirm whether the control or the parts are at fault.
Why we replaced the heater and thermostat together
The defrost heater and defrost thermostat age together and live in the same cold, wet spot. Replacing only the failed heater on an old refrigerator often leads to a second visit months later when the thermostat goes. Because both parts sit behind the same panel, replacing them together saves labor and gives the owner years of reliable defrosting.
Is a frost repair worth it on an older GE?
Defrost repairs are among the most cost effective refrigerator repairs because the parts are simple and the sealed system is not involved. If the compressor runs normally and the cabinet is in good condition, repairing a 10 to 12 year old refrigerator with a defrost failure usually makes sense. Our refrigerator not cooling guide covers the other parts that cause a warm fridge.
Seeing frost on your own refrigerator? Read our refrigerator and freezer repair guide or learn why ice makers freeze up.
Common questions
Why is my GE refrigerator freezer frosting up?
A failed defrost heater, defrost thermostat or a door that does not seal fully lets frost build on the evaporator coil. Testing the heater and thermostat for continuity confirms which part failed.
How do I unclog a defrost drain on a GE refrigerator?
Unplug the fridge, remove the freezer back panel and pour warm water into the drain hole until it flows to the drain pan. If ice keeps forming in the drain, the defrost heater may be weak.
How long does a GE defrost repair take?
Usually about an hour once the ice is melted. If the coil is heavily iced, the freezer may need to defrost first so the panel can be removed safely.
Can I use a hair dryer to defrost the freezer?
Only carefully and on low, held well away from plastic parts. Letting ice melt naturally with towels and a fan is safer.
