To begin, you will need a pot of boiling water with at least 4 inches of water in it, and an ice bath. Run duplicates on each sample. Place the non-calibrated thermometer in the boiling water. To calibrate your thermometer in boiling water, bring clean water to a boil and place the thermometer probe into the boiling water for at least one minute. Boiling Water Method Take some water to boil it in a deep bowl. Make sure the sensing area is under water. How to Decorate Kitchen Tables With Flowers & Candles, How to Check a Water Well That Has Been Inactive, How to Get the Ice Machine Working on a Fridge, The University of Wisconsin-Madison, Food Safety and Health: Using and Calibrating a Dial Stem Thermometer. To ensure that your poultry is cooked to a safe temperature without drying it out, or to accurately grill a steak to a medium-rare or well-done order, it is important to take a precise temperature reading. Here’s how: Step 1: Bring a pot of water to boil on the stove. This can be accomplished with a properly calibrated food thermometer. When doing this it is important that the thermometer used for the comparison has been calibrated recently. Insert the thermometer's probe or stem into the middle of the glass so that it is not touching the bottom or sides of the glass. Keep the stem of the thermometer in boiling water. Step 2: Fill a glass or small bowl with ice and cover with water. Do this while the thermometer is still in the boiling water; the instant you remove a thermometer from the boiling water, the temperature will start to drop. Some parts of this site work best with JavaScript enabled. The reading should be 100 degrees Celsius. When the water reaches its boiling point, place the sensor into the water and make sure that you keep it as close to the center as possible, away from the sides and bottom of the container. Put the thermometer stem or probe into the ice water. When using the boiling water method, be sure to consider your geographic location; the boiling point of water is 1 degree F lower for every 550 feet rise above sea level. (Read manufactures directions on care of the pH electrode before using this procedure). Blender cups, beakers and stir bars can be rinsed in distilled water between samples. Like in the ice-water method, ensure your thermometer is immersed in boiling water at least two inches deep. Pukomc 1.8L Electric Water Kettle with Thermometer, Hot Water Boiler & Tea Heater with Curved Handle, Visible Water Level Line, Led Light, Auto Shut-Off&Boil-Dry Protection 4.6 out of … Changes in atmospheric pressure at elevations above or below sea level alter the temperature at which water boils. The thermometer probe should not contact the boiling water. Allow the thermometer to settle for about thirst seconds and take the reading. Any thermometer that has been subjected to abuse, such as being dropped on the floor, should be immediately recalibrated to assure accuracy. How Does a Thermometer Measure Temperature. True or False. Insert the thermometer to cover the entire sensing area. HOW TO CALIBRATE A THERMOMETER Using the Ice-Point Method to Calibrate a Thermometer Fill a large container with crushed ice. Boil a pot of distilled water. These thermometers are generally adjusted with a zeroing screw. With the Fahrenheit scale, Daniel Fahrenheit decided that the freezing and boiling points of water would be separated by 180 degrees and he pegged freezing water at 32 degrees. How to Calibrate a Thermometer. Stir the ice chips and water. After 30 seconds, your thermometer should read 32° F. If it doesn't, it may need to be replaced or recalibrated. If you have a digital thermometer, press the reset button to adjust the temperature. Therefore 2 degrees must be subtracted from the temperature displayed when taking a reading in food to find out the true temperature. If your thermometer doesn’t have any faults, it will read 212°F when placed in boiling water at sea level under normal atmospheric conditions. Boiling Water Test. Boiling Water Method Instead of using ice water, you can use boiling water, especially if you plan to use the thermometer primarily for hot foods. and record the reading of the thermometer. Pour cold water into the glass right up to the brim, then stir it for 15 seconds. In this second round, the thermometer should read 32 degrees F without requiring any adjustment. Michelle Brunet has published articles in newspapers and magazines such as "The Coast," "Our Children," "Arts East," "Halifax Magazine" and "Atlantic Books Today." Place the stem or probe into the boiling water so that at least 2 inches of the stem are immersed; the stem should not be touching the sides or the bottom of the pot, as this will affect the reading by making it too high. Fill a large container with crushed ice and water. Follow these steps to complete the calibration: Bring a pot of water to a rolling boil. Bring the water to a rolling boil. While thermometer is in the boiling water adjust the thermometer to 100ºC (212ºF), if necessary, by following the manufacturer's directions. Hold the calibration nut and rotate the thermometer head until it reads 32 degrees f (0 degree c) Only use glass thermometer when. If the thermometer does not read between 210° and 214° F adjust to 212° F. Non-adjustable thermometers should be removed from use until they have been professionally serviced. A reading between 200 and 214 degrees Fahrenheit is within the range considered accurate. 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