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The ThermoPro TP420 is a two-in-one instant infrared and probe thermometer.
You basically get two thermometers for the price of one.
The TP420 can be used as an instant-read meat thermometer by folding out its probe to insert it into meat to check the internal temperature.
You can also use the TP420 as an infrared thermometer to measure the surface temperature of your cooking surfaces.
All you have to do is point the infrared sensor on the end of the thermometer and press the “scan” button.
There is often a compromise in quality whenever a single device is created to do the same job as multiple devices.
Is that the case with the ThermoPro TP420? Great question.
I can confidently say that the TP420 is accurate when used as a probe thermometer and as an infrared thermometer.
Are there compromises that come with this thermometer? Yes.
In this review of the ThermoPro TP420 Two-in-One Instant Infrared and Probe Thermometer, I will discuss these compromises as well as its features, usability, accuracy, durability, and price to determine if it’s a thermometer that fits your cooking needs.
ThermoPro TP420 Two-In-One Infrared and Probe Thermometer
There aren’t many thermometers on the market that can act as both an instant-read probe thermometer as well as an infrared thermometer.
The ThermoPro TP420 joins the Thermoworks Thermapen IR as one of the few thermometer models capable of both types of temperature measurement.
However, the TP420 costs about $115 less than the Thermapen IR.
Thermoworks produces the highest quality meat thermometers on the market so that price is justified.
But is it possible to get adequate results without the high price tag?
After testing the ThermoPro TP420 in multiple cooking tests I can safely say that it is up to the task of accurately measuring cooking surface and food temperatures.
Here are all of the important features and specifications of the ThermoPro TP420.
- One Infrared Sensor
The infrared sensor has a range of -58ºF to 1022°F (-50°C to 550°C). It is a Thermopile Sensor with a 12:1 Distance Spot Ratio.
- MAX/MIN/AVG Temperature
There is a dedicated middle portion of the display for displaying the maximum, minimum, or average temperature of the infrared sensor.
- One Stainless Steel Temperature Probe
The probe is an NTC-type thermistor probe with a range of -58ºF to 572°F (-50°C to 300°C). It is rated accurate to within +-1.8°F (+-1.0°C) and has a response time of 2 to 3 seconds.
- Power/ SCAN Button
The power button also acts as the scan button for the infrared sensor. Pressing the button turns on the thermometer. Press and hold the button to scan and measure the surface temperature of where you’re pointing the sensor.
- Mode Button
Press the mode button to cycle through the max/min/avg temperature readings of the infrared sensor. Press and hold for 3 seconds to enter the emissivity adjustment mode.
- Celsius/ Fahrenheit Button
- Backlight Button
I mentioned earlier that there are some compromises with this thermometer.
All of these trade-offs are related to viewing the digital display when using the thermometer as an infrared thermometer and as a probe thermometer.
The temperature display is fixed and doesn’t rotate. This is due to the fact that there are three separate temperature displays on the screen.
To use the infrared sensor to measure the cooking surface of a pan or griddle you need to point the TP420 down towards it.
The infrared sensor has a 12:1 distance-to-spot ratio.
This means that you can hold the thermometer’s infrared sensor 12 inches away from the surface you want to measure and it will take the temperature of an area of 1″ in diameter.
There isn’t a laser dot to pinpoint where exactly you’re pointing, but you can get relatively close to where you want it just by “eyeballing” it.
To use the infrared sensor all you need to do is press the scan button. By holding the button down, the sensor will remain active, scanning the cooking surface.
The middle part of the display screen will show you the minimum temp, average temp, and maximum temp of what you just scanned. Pressing the Mode button on the device allows you to toggle through these values.
To be able to see the temperature on display you will need to tilt your neck to see it properly.
The same situation goes for using the probe part of the thermometer.
It is difficult to see the temperature from the traditional angle in which you insert a meat thermometer into food.
The probe of the TP420 folds straight down and then out from the device body.
This design is so you can view the display by folding the probe down at a 90° angle and then inserting it into your food.
This type of probe configuration can be hard to use when taking the temperature of a thin piece of meat or a sausage cooking on the grill.
Is it a deal breaker? Absolutely not.
Getting two thermometers that are accurate and fast for the price of one is well worth the hassle of having to crane your neck a little bit.
I tested the accuracy of both the probe thermometer and the infrared thermometer of the TP420 against other highly-accurate thermometers.
First, I tested the probe portion of the TP420 alongside the FireBoard SPARK thermometer by measuring a 140°F measuring cup of hot water.
It was spot on in terms of accuracy and the response time was 2 to 3 seconds.
Next, I tested the infrared sensor by measuring the temperature of a pan heating on the stovetop.
It showed similar results to the highly accurate Thermapen IR in reading the surface temperature of the pan throughout testing.
The one area of concern with the TP420 might be its durability.
There is no waterproof rating. This is probably due to the opening for the infrared sensor on the end of the thermometer and the lack of a seal on the battery cover.
This shouldn’t be a major issue as long as you don’t feel the need to wash the thermometer off under running water.
To clean this thermometer or any thermometer for that matter, all you need is to spray a paper towel with some bleach water and wipe it down. Germs are killed and you don’t run the risk of ruining it.
There are nice rubber grips on the outer sides of the thermometer that should buffer some shock if the thermometer is dropped.
They also make it easier to hold onto with greasy hands.
In the price section of my reviews, I will usually show how a thermometer compares in price to similar thermometers.
Having already mentioned the much more expensive Thermapen IR, there really aren’t any good comparisons to the TP420.
The price is very reasonable at $29.99.
There aren’t many meat thermometer companies that I trust making a purchase under $30.
There are a lot of junk thermometers in this price range.
ThermoPro produces high-quality products and has great customer service.
If you’re intrigued by an infrared thermometer/probe thermometer combo I would say this is a great value.
If the display issues prove too much of a burden, ThermoPro will take it back within 30 days of purchase, no questions asked.
They also offer a three-year warranty once you register your product as well.
This one’s pretty easy to sum up. The ThermoPro TP420 does the work of two thermometers and it is accurate on both counts.
Yes, the display can be burdensome by having to adjust your neck to see it during certain cooking situations, but that is a small price to pay for getting two accurate thermometers for one low price.
If this is your first time reading one of my reviews, welcome.
In case you think every review is as positive as this one, it’s not.
I’ve been highly critical of many models. I don’t like being negative but I hate being dishonest even more.
I like when a thermometer is a quality product, it just makes my job easier. Thank you TP420.
I rate it a great buy.