Apr 07, 1983 · The kerosene heater trade group notes that cotton wicks have a limited life, but by trimming off an eighth of an inch once a year, you can preserve the life of the wick. Carbon deposits on the ... The only surprise was the cost of k-1 kerosene which is $8.38 a gallon at Walmart and $10.38 a gallon at Home Depot but the heater burns very efficiently so it doesn’t guzzle fuel to waste it. I should have bought one with tires and carrier because it is heavy with 5 gallons of fuel.