A base pan heater is an electric heating element installed in the bottom of an outdoor condenser unit to prevent ice from accumulating in the drain pan. During the winter, when a Heat Pump Condenser runs its defrost cycle, melted ice can refreeze at the bottom of the unit, potentially damaging the fan blades or the coil. This heater ensures that the water remains in liquid form and drains away completely, even in sub-zero temperatures. Many ACIq and MrCool units come pre-equipped with these heaters for extreme cold-climate performance. If your system does not have one, you can often find them as a field-installed accessory in our Accessories-Kits collection. This small component is essential for maintaining the structural integrity and quiet operation of your unit throughout the harshest winter months. Without a functional base pan heater, the unit can become a solid block of ice, leading to complete system failure.