The situation when the refrigerator stops working is always unexpected and unpleasant. Especially on the eve of a large feast or in extreme heat, when it is necessary to carefully monitor the freshness of the food. Often, owners face a different problem when the freezer works, and the refrigerator practically does not cool. Such a breakdown is rarely immediately noticed, since the indicator of serviceability is not the indicators on the thermometer in the refrigerator, but the freezer, which continues to work well. A difference of several degrees is difficult for an ordinary person to feel, but the food in the refrigerator spoils extremely fast. The refrigerator may have one or two thermistors located in different areas to monitor the temperature in the refrigerator section. These sensors send their signal to the main control board, which may turn on/off the compressor or evaporator fan motor, or open/close the air damper to let more or less cold air into the refrigerator compartment. When one of these sensors fails, it can cause the temperature to be off or even cause the refrigerator not to run. Thermistors rarely, if ever, fail completely, although we sometimes see a thermistor fail due to an open circuit resulting from a break in wires between the thermistor and main control board. This usually happens when wires are spliced incorrectly allowing moisture penetration. The most common reason why thermistors fail is simply aging. Over time, sintered non-oxides in thermistors lose their efficiency and provide signals that are no longer accurate. You can test your thermistor(s) using an ohm meter or multimeter. The best way to do this is to remove the thermistor from the refrigerator so you can control the temperature of the sensor. You can let the sensor warm up to room temperature or grab a glass of ice water to test the thermistor. With the sensor warmed up to room temperature the sensor should read approximately 6.2K Ohms at 68°F. With the thermistor submerged is a glass full of ice water, the sensor should be very close to 32°F which should read approximately 16.3K Ohms. If the values that you are getting are far off from these readings, then the sensor is bad and should be replaced. If the reading you are getting is not consistent; where sometimes the ohm reading is correct and other times it isn’t, even though the temperature hasn’t changed, then the thermistor should be replaced. Don’t hesitate to give us a call or contact our customer support team for additional details!
November 26, 2023
AC is leaking from the coil – HVAC Troubleshooting in San Diego
Have you encountered a leaking air conditioner? This causes not the most pleasant feelings and deprives you of comfort. Before solving this problem, you should determine what exactly became the source of the air conditioner flow.