When a thermostatic expansion valve is installed in a refrigerated container unit, the sensing bulb almost always requires insulation. Why is this so?

Correct Answer: Option A — the insulation prevents air stream temperatures from influencing the bulb temperature

Insulating the thermal expansion valve sensing bulb isolates it from ambient air currents in refrigerated spaces, ensuring the bulb measures true suction line temperature rather than surrounding box air, which prevents erratic valve hunting and compressor flooding.