Generac 9-22 KW Air Cooled Generator Oil Heater Kit. This 240V, 50W, .21A oil heater is designed for use with the battery warmer on Generac air cooled standby generators in areas that experience freezing temperatures. It conveniently slips directly under the oil filter and is compatible with units manufactured from 2008 onwards. Backed by a 1-year limited warranty, this oil heater ensures reliable performance and peace of mind during cold weather conditions.