Depending on how many you have I run around 100 hives, so in the fall I warm up a 45 gallon drum 1/2 full of water and dip the queen excluders in the drum , it takes about 10 seconds and the excluders are clean and ready to go. Expanding on the warm up part I set the drum on a propane outdoor deep fryer. takes about 20-30 minutes to get get the water to temp.