Troubleshooting: Thermapen Mk4

Here are answers to some common technical support questions about the Thermapen Mk4.

How do I change my Thermapen Mk4’s resolution display?

How do I change my Thermapen Mk4 from °F to °C?

How do I change my Thermapen Mk4’s battery?

My Thermapen is flashing “flae” messages. Is this an indication I need to replace the battery?

Yes it is. That message is “Flat Bat”. Because of the limited segments, it can appear to read “Flae Bae.”

I accidentally broke my Thermapen Mk4’s battery cover. How do I get a replacement?

We are happy to send you a new battery cover at no charge. Please contact our Tech Support and they will send you one right away. Their contact information is found below.

Where can I get instructions for the Thermapen Mk4?

Thermapen Mk4 Operating Instructions can be downloaded here.
Thermapen Mk4 Trim Adjustment Procedure can be downloaded here.
Thermapen Mk4 Product Info Sheet can be downloaded here.

How do I test my Thermapen for accuracy?

An ice bath test is the best way to verify the accuracy of your Thermapen Mk4, because it’s a standard laboratory test that is easily replicated at home. Directions for making a proper ice bath are found here.

If your Thermapen is accurate, it will read within ± 0.7°F of 32°F (31.3 to 32.7°F). If it is reading accurately in this test, you can rest assured that it is reading accurately in food and at higher temperatures.

My Thermapen Mk4 recently stopped working without warning. I’ve replaced the batteries, but it didn’t help. Can you help?

While it is extremely rare that a Thermapen Mk4 suddenly stops working, we are sorry that it has happened to you. Our Tech Support team needs to take a look at your Thermapen to determine what has gone wrong. If we discover that the issue is covered by warranty, we’ll either repair or replace it without charge (depending on the source of the issue.)

If we discover that the issue is related to a problem not covered by the warranty, we offer affordable repair services for $40, which includes return shipping.

Please contact our Tech Support team and they will set up a Return Authorization for you.

My Thermapen doesn’t turn on until the probe is in the fully open position. Is this something you can fix? How much will it cost?

In most cases when we see this error, it is because foreign matter has worked its way into the rotating hub. While there is an O-ring seal inside, oils, moisture, flour, or fine powders can work their way past the seal over time and accumulate in the housing, interfering with electrical components. This particular issue is one that we need to repair for you. If we discover that the issue is covered by warranty, we’ll either repair or replace it without charge (depending on the source of the issue.)

If we discover that the issue is related to a problem not covered by the warranty, we offer affordable repair services for $40, which includes return shipping.

Please contact our Tech Support team and they will set up a Return Authorization for you.

My Thermapen is displaying “Err”on the screen when I unfold the probe. What does this mean?

When a Thermapen’s display reads Err, it usually means the probe has been damaged and needs to be repaired. Please contact our Tech Support team and they will get the process started right away.

What does it mean that my Thermapen is displaying a “C.Lo” error?

The C.Lo message means that the Thermapen is trying to go into calibration mode. When the Thermapen does it on its own, it usually means that there is something wrong inside the Thermapen. We recommend that we take a look at it.

If we discover that the issue is covered by warranty, we’ll either repair or replace it without charge (depending on the source of the issue.)

If we discover that the issue is related to a problem not covered by the warranty, we offer affordable repair services for $40, which includes return shipping.

Please contact our Tech Support team so they can help you. The information you need is found below.

I am seeing some inconsistencies with the backlight. At times, I can get it to come on by covering the sensors, but not always. Is there some sort of setting to configure it?

The Thermapen Mk4’s intelligent backlight turns on if it is exposed to enough ambient light. If there is too much ambient light, it won’t turn on and it may appear that the backlight isn’t working.

If you need to activate the backlight, cover the light sensor (the dot) located on the right-side of the display window with your thumb. If that doesn’t work, cover the sensor and part of the display with your palm. Once triggered, the backlight will stay on for 10 seconds.

If your Thermapen’s backlight isn’t working as expected, please contact our Tech Support team. They’ll be happy to help you.

My Thermapen Mk4’s screen has been getting cloudy. Is there anything I can do?

By chance, has the display been cleaned with isopropyl alcohol?

We have found this to cause the screen to appear cloudy, when in fact, it is more consistent with etching of the display.

We do offer affordable repair services for the Thermapen for $40 and would be happy to send you a Return Authorization for repair. Our Tech Support team can help you with that.