I have a Kenmore freezerless refrigerator model 253.44723106, about 15 years old. The issue is temperature fluctuation. Started 2 weeks ago. Gets down to 36 at times, but then up to 46 at times. The fridge is used for drinks only and isn't opened more than twice per day. 2 months ago a technician came out when there was no cooling at all. Said compressor was fine. Replaced the compressor starter and all was good for roughly two months. Any thoughts as to other causes?