Compressor Starting With Failed Start Relay??? How Can This Be?

[Applianuser]

Three weeks ago, the freezer section of my Samsung refrigerator (twin cooling) just stopped getting cold. No warning or previous symptoms. No error codes flashing. None coming up during self-diagnostic. The fridge section is also only getting down to 50 degrees. Here's what I've checked so far:
- Set temps: Freezer -2, Fridge 34.
- Actual room temps: Freezer 70, Fridge 55.
- No icing on the evap coils.
- All temp thermistors tested accurate.
- All fans tested fine.
- Condenser coils clean, and fan working.
- 115V present on SMPS PCB. DC170 found at BD1 rectifier (good).
- 12V and 5V outputs on SMPS PCB good.
- Front panel seems to operate normally.
- Test mode works as it should. As does demo mode.
- Tried resetting several times and left unplugged for a couple hours. No change.
- Compressor starts fine. No unusual noises. No short cycling.
- No continuity when testing start relay (DA35-00103B, PTC thermistor). Relay resistance tested very high - 1.2K ohms at room temp.
- OLP tested fine.
- Run cap tested fine.
- The compressor also stops running before reaching set temps. This could be due to OLP kicking in.

Q. So, how is the compressor starting with a failed start relay?
Q. Could a failed start relay cause the compressor to start but not cool the unit effectively?

[Nathaniel Peterson]

On 7/1/2024 at 9:31 PM, Applianuser said:

Three weeks ago, the freezer section of my Samsung refrigerator (twin cooling) just stopped getting cold. No warning or previous symptoms. No error codes flashing. None coming up during self-diagnostic. The fridge section is also only getting down to 50 degrees. Here's what I've checked so far:
- Set temps: Freezer -2, Fridge 34.
- Actual room temps: Freezer 70, Fridge 55.
- No icing on the evap coils.
- All temp thermistors tested accurate.
- All fans tested fine.
- Condenser coils clean, and fan working.
- 115V present on SMPS PCB. DC170 found at BD1 rectifier (good).
- 12V and 5V outputs on SMPS PCB good.
- Front panel seems to operate normally.
- Test mode works as it should. As does demo mode.
- Tried resetting several times and left unplugged for a couple hours. No change.
- Compressor starts fine. No unusual noises. No short cycling.
- No continuity when testing start relay (DA35-00103B, PTC thermistor). Relay resistance tested very high - 1.2K ohms at room temp.
- OLP tested fine.
- Run cap tested fine.
- The compressor also stops running before reaching set temps. This could be due to OLP kicking in.

Q. So, how is the compressor starting with a failed start relay?
Q. Could a failed start relay cause the compressor to start but not cool the unit effectively?

If the compressor is running and no cooling at all you should check the amps at the compressor. If it's running with no refrigerant I could see it running without a start relay as it uses less amperage when low or out of refrigerant.