How to Check if your Thermometer is Accurate

Jason Webster
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Why you should test your thermometers regularly

Water heating temperature can make a big difference in frying time. If your thermometer reading in the kitchen differs from your thermometers reading in the salon, that’s a big problem.

When the oil gets much hotter than the recommended frying temperature, burnt foods are inevitable. You should test the accuracy of your thermometer with water when the kitchen is not too busy and all of your staff is available.

To test the super accurate thermometer, you will need to buy an inexpensive copper stick from the hardware store. This can be purchased for a few dollars.

It is a good idea to wear protective gear including heavy wrinkled oven gloves to protect your hands from burns. Heat the copper stick in the microwave for a few seconds, until it is red hot.

Depending on the type of thermometer you have, you can dip the copper stick into the oil, or you can place the tip of the stick a few inches away.

Then you will have to wait for the copper to cool and mark the height of the copper on the stick.

Mark the measurement on your kitchen wall and check the reading against your cooking thermometer to see if they are the same.

You need to check your thermometer specs

If you want to know whether it will provide accurate results.

There are two kinds of thermometers. Digital and dial. Sometimes they’re called “instant-read” thermometers because of the way you use them.

Digital thermometers are the quickest to read, but will often sacrifice accuracy for speed. They come in various shapes and sizes, and can also be digital or dial thermometers.

The digital thermometers usually have an auto shutoff function. When the sensor is left in place for a certain amount of time, the temperature reading is locked into the display. This prevents the thermometer from going into what’s called “thermometer-bricking mode.” This is when the thermometer gives you the average last reading indefinitely and is therefore useless to you.

Dial thermometers are a bit easier to use and are not as fragile as their digital counterparts. You can check the accuracy by checking the temperature versus a known, accurate thermometer and calibrating if necessary.

To validate the accuracy of your thermometer, you can take an ice water bath. This way you can be sure your thermometer will be at the desired temperature without the risk of altering the temperature of the bath.

Other tips to make sure your thermometer is accurate:

How to Test Your Thermometers Accuracy

Whenever you are using a thermometer, it is important for you to check its accuracy. This will ensure that the reading you get is accurate.

Remember, some thermometers rely on mercury or alcohol for their temperature reading.

The best way of understanding whether your thermometer is accurate is to compare its reading to another thermometer.

A. The Old-School Method

If you own a liquid thermometer, one way to compare its accuracy is by placing both the thermometers in hot water. Both should read the same temperature. If the old thermometer says the temperature is 31 degrees C, its accuracy is about +/- 2 degrees.

B. Digital thermometers are easier to compare

Digital thermometers are also easier to check for the accuracy. Simply place them alongside on a wall or on a table under the same temperature condition.

If one thermometer reads 23 degrees C and the other reads 27 degrees C, the accuracy of both thermometers is about +/- 2 degrees.

One thing to be careful about is that the digital thermometers have advanced processors and sensors. These thermometers are often not as accurate as a mercury thermometer. However, they are extremely accurate and reliable. It is important to understand how the digital thermometer works as they can also be inaccurate depending on how well they are made.

The Boiling Water Test

Thermometers can be quite precise nowadays.

But if you want to be sure that your reading is as accurate as possible, you should try the boiling water method.

Just fill a pot full of water and place it on the stove on low-to-medium heat. Once the water starts to boil, check your thermometer.

If it matches the temperature shown on the thermometer (or a few degrees higher), then you are good to go. If it shows a different temperature, adjust your thermometer by about 1 degree higher or 5 degrees lower, and check again.

You want your thermometer to read the temperature of boiling water to be within some degree of accuracy.

If you use your thermometer less than 5 times a year, it is highly unlikely that its accuracy will have degraded to the point of being annoying.

If you use your thermometer regularly however, you should check its accuracy every 3-6 months. This will make sure that your readings are always accurate. Make the most out of your thermometer. Buy a quality device and then take good care of it!

The Ice Bath Test

The ice bath test is a great way to test the calibration of an analogue thermometer.

The ice bath is an ideal place to achieve a temperature consistent of at least -10 C.

Fill a bath with 0 C cold water and ice and place your thermometer on top of a container in the bath.

Wait until the temperature is consistent and make a note of the reading on your bulb thermometer.

Next, remove the thermometer from the bath and hold the glass away from the contents inside the container.

This way the heat will not influence the thermometer and you can read the temperature on the thermometer body.

Check to see if the two readings are similar and if they are not, see if by using the different temperature as a reference point will help you determine if your thermometer is accurate.

How to calibrate an inaccurate Thermometer

Have you ever tried to boil some water on a hotplate that wasn’t on?

I have.

I was determined to make hot chocolate on a snowy day when the electricity went out in my house. I was pretty certain that the hotplate on my cooker would do the job. I set it on the lowest setting and waited about 20 minutes for it to start simmering some water. But the water never did. I kept waiting and watching the thermometer hoping that I wasn’t going to have to wait all day for the water to boil.

After 30 minutes I gave up and went to check on it. To my surprise, the hotplate was actually stretched out to its maximum setting.

The thermometer was terribly wrong.

The point is that even though that thermometer was supposed to be a precision instrument, it wasn’t.

The bottom line is that you can trust the accuracy of a thermometer only if you know where the error lies.

As long as you know the error in your instrument, you can calibrate the thermometer to compensate for it.

The way you calibrate a thermometer is by placing it in water (a pot of hot water, cold water, rain water or air) and recording the point at which it reads 58 F (14.5 C).

Knowing how to calibrate thermometer is important.

Being able to make sure that your thermometer is accurate at all times is essential to the healthy lifestyle of your fish and plants. Calibrating the thermometer involves checking if the thermometer is set at the right parameters.

What this means is that if your thermometer does not show the right temperature, you should adjust it so that you are reading the true temperature.

Checking Accuracy of a Thermometer

You should check the accuracy of your thermometer every time you place it into your aquarium. The ideal temperature should be about the same temperature where your fish are naturally found.

Fish that are found in cold water can survive in warm water, but they live much longer in cooler conditions. So what this means is that you need to make sure that your thermometer is showing the right temperature.

If it is not, you need to calibrate it.

The easiest way to determine if your thermometer is accurate is to use a substance which is about the same temperature as the water in your aquarium.

Step 1

Get your thermometer. If you are using a glass thermometer, heat water in a kettle to the correct temperature. Place that water into a shot glass. If you are using a digital thermometer, fill a glass with cold tap water.

Calibrate ThermoWorks Thermapen

If you are using a thermometer for cooking meat on an outdoor grill, we recommend the Thermapen series by ThermoWorks. The instant-read thermometer is the best we have found for a kitchen or a grill.

This family of thermometers generally is more accurate than the devices checked against it in water baths. For example, a thermometer that measures sugar concentration for candy making is checked against a water bath. Another, a thermometer that measures altitude inside a plane is checked against a water bath. For a Thermapen or other thermometers that are checked against a water bath, results are accurate to within +/- 3%.

We recommend that if you are cooking whole beef tenderloin at 225°F on an outdoor grill, you want to measure the internal temperature. For that, we recommend a digital instant-read thermometer like the Thermapen.

There are two options to check accuracy of this thermometer.

Thermal couples are accurate. They measure the temperature of two points in which the thermal difference is very high. When you test a thermal couple, you need to use distilled water. If you use tap water, you can get a false low reading where air bubbles are trapped. If you take a high reading, it is due to boiling the water.

How to calibrate Infrared Thermometers

There are two main types of thermometers: the ones that measure the air temperature and the ones that measure the temperature of the surface on which you place them.

In order to measure accurately, they have to be calibrated.

The most accurate way to calibrate them is to put them in boiling water for 2-3 minutes. This will help the thermometer get the correct temperature reading.

Calibrating a thermometer is much easier than you think.

Before you put anything in the boiling water, fill a bowl with cold water and place the thermometer inside. Make sure it’s submerged in the water and that the temperature is close to the thermometer’s range. This will help it read the correct temperature when it’s in boiling water.

Switch on the thermometer and let it stay in the water until the screen displays the correct reading.

It is best to pursue this process with a certified thermometer. This will ensure the calibration is correct.

Be sure to cover the sensor area with insulating material during calibration. Temperature changes from the surface could affect the reading.

Tips to Keep your Thermometer Accurate

Ever feel like your thermometer is always too cold?

Ever feel like your thermometer is always too hot?

You know that taking an indoor temperature reading is always a bit tricky.

See, the temperature in your home is often different from the outdoor temperature.

If you rely on a thermometer exclusively for taking an accurate temperature reading, you can’t really tell how accurate it is.

Other variables such as outside temperature, wind, sunlight, air pressure, placement of thermometer, humidity, etc. can also influence the accuracy of your thermometer.

If you’re using an infra-red or battery-powered thermometer, the battery life can often be limited which can affect the readings.

Tomahawk Steak Guide – Where to Buy, How to Cook and Are They Worth the Cost?

A tomahawk steak, also referred to as cowboy steak or bone in rib eye, is an impressive and tasty piece that is perfect for special occasions.

What makes this steak special is the way it is trimmed.

It is bone-in, has a relatively thick strip of fat on top, and has a crust of salt, pepper and herbs which basically makes it look like a rack of genuine ribs.

Whether you like to call it a tomahawk steak or a cowboy steak, it is often a little pricier than a regular rib eye of the same size.

So, do prices justify this special meat? In order to answer this question, I have studied different aspects of the tomahawk steak.

Let’s first take a look at how this meat is served, how to cook it, and is it worth the price tag.