A common problem that happens with refrigerators or freezers is that they stop getting cold or aren’t getting as cold as they used to. There is a few things you can check before calling a repairman. This problem in a lot of cases is caused by frost buildup on the evaporator coils. One of the ways you can tell this is the problem is looking for frost buildup inside the freezers, such as on the walls or floor. This means there could be a problem with the self-defrosting system. Unfortunately, the only way to determine this is to remove all the food from the refrigerator and freezer, shut off the thermostat, and leave the doors open until it manually defrosts (usually about 24-48 hours). Be sure to have a lot of towels around the fridge to catch all the water.
Once everything has melted, turn the thermostat on and see what happens. If everything is cooling properly again, it means the issue lies with the defrost timer, defrost thermostat, or the compressor. You might be able to replace the thermostat or timer yourself, but if it’s the compressor, you’ll have to call a repairman, such as appliance repair houston to properly diagnose and repair the issue.