I have a walk-in-freezer that, whenever it went into defrost, condensate water was dripping from the drain onto the floor. The drain runs outside and I knew I had big problems because no water was coming out of the drain.
I pulled the insulation off the drain line and found two gaping splits in the copper tubing. Not only that, whoever fabricated the drain, field fabricated a trap from copper tubing and elbows. The trap was about 3" deep. Also, the braided pipe heat cable was shorted out. Further investigation revealed the leads from the cable ran over the top of the drain pan, over the drain pan heaters and finally to the evaporator coil terminal board. One lead was connected to "N" and one lead was connected to "3" on the evaporator coil terminal board which meant, even if the heat cable wasn't shorted out, it would be energized only when the system went into defrost.
So, to solve the issue once and for all, I plan on re-piping the drain and doing away with the trap. I plan on replacing the drain line heat cable with a 15' 120V heat cable, wrapping and securing the heat cable around the copper drain line, insulating with 1" wall tubing insulation, installing a dedicated 120V GFCI receptacle behind the evaporator coil and plugging the heat cable into it.
I asked our staff electrician what he thought and he said he had never heard of installing a receptacle inside a walk-in-freezer for a drain line heat cable. I told him I had seen it done this way many times. Is this what you would do in this situation? In not, what do you suggest I do? Thanks.