pressure

local compressor = peripheral.wrap("left")
local dPressure = compressor.getDangerPressure()
while true do
  local pressure = compressor.getPressure()
  print("Compressor Pressure: "..pressure)
  if pressure <= dPressure / 2 then
     rs.setOutput ("left", true)
     print ("Refueling")
     turtle.turnLeft()
     turtle.drop(1)
     turtle.turnRight()
    compressor = peripheral.wrap("left")
 else
     rs.setOutput("left", false)
 end

  turtle.select(1)
  if turtle.getItemCount(1) < 1 then
    turtle.suckDown()
    print("Need Coal..")
 end
 print ("Waiting 10sec..")
 sleep(10)
end