Maple syrup finishes at 7ºF above the temperature of boiling water. The temperature of boiling water will change based on your altitude and current barometric pressure. Because of this, it is recommended to calibrate your thermometer in boiling water at the beginning of each day. When your thermometer reaches the bold 7 mark, you can open the draw-off valve and draw that syrup into a separate vessel for filtering. It is normal for the temperature to climb a little while you first start to draw off. When the temperature drops below the bold 7 on your thermometer, gently close the draw-off valve. The sap that remains in your evaporator pan needs to continue boiling. It is best practice to do a periodic hydrometer test to double check the density.
Various Sizes Available from Smoky Lake