When you get a full unit, or FU, message on your air conditioner unit, that means that the tank is filled with water. As your air conditioner runs, it produces condensation that collects in a resevoir tank.
Every so often, that tank will need to be emptied. In the video below, our technician will show you how.
Transcript: So this is our model between a range of 1 ton to 2 ton unit. So right now I’m going to demonstrate what happens as the unit’s running for a while it starts making condensation.
So what happens is, there’s a five gallon container on the backside of this unit that’ll proceed to drip water all through the evaporator coil and fill this jug. Over time, this jug will fill. The float will meet a sensor, and it will tell the display, “FU,” which means full unit, and then you’ll have a little red light that says water full.
So what you have to do in the meantime is actually remove the tank–gently, you don’t want to spill everywhere–gently remove the tank and find a sink, basin, or wherever you can to be able to throw it down a drain. Empty the water, and then gently replace the tank back. So what you’ll presently see is that it’ll remove the FU error code and it’s ready to go back in standard operations. You’ll never get cold air coming out, you’ll have still blower fan when it comes out, and then that tank’s full, but you’ll never get cold air so just check to see for that error.