As professional Appliantologists, we've all run into situations where we realized that we needed a way to log temperature data inside a refrigerator for at least 24 hours to get a clear picture of what's going on inside that box. A couple of examples are:
Customer complains of warm temperatures in the beer compartment of her Maytag side-by-side refrigerator but says that the freezer compartment is fine (and we know how accurate customer temperature measurements are... NOT!). You arrive and measure the freezer temperature using your infrared temperature gun and get readings that vary from +5F to +12F. Marginal temperatures for a freezer but was that because it was just coming out of a defrost or off-cycle? Was the door recently opened just before you got there? You don't know and all you have is the one data point: the measurement you just made. Wouldn't it help your diagnosis if you could put a data logger inside the freezer for a day or so and then look at a graph of the actual temperature measurements inside that freezer over time?
Customer complains that the freezer temperature in her GE built-in refrigerator fluctuates over time from 5F to 10F to 20F and then back to hard freeze. You maybe even verified this yourself (if you spent enough time there to do this). But how much time in a typical service call day do you have to babysit freezer temperatures? And you still wouldn't be able to gather enough temperature-time data points to discern whether or not there's a pattern to the fluctuations which could then be correlated to some other process in the refrigerator (defrost cycles, compressor cycles, etc.). Even seeing that there is no pattern, that the fluctuations are random, is also helpful because it could indicate something as simple as the door not being closed all the way (hinge adjustment issue?).
See what I be sayin', mah bruvah? In cases like these (and many others-- I'm sure you can think of several that you've been on), you just gotsta be able to look at the temperature inside the compartment over an extended period of time. Enter the Supco LT2 LOGiT Dual Channel Temperature Data Logger:
Which needs the Supco LOGiT software package to enable it to connect to your Windows PC to set it up and download the data:
...and it all works AWESOMELY! Here's a video I made showing you how to set up and use the LT2 and the type of temperature profile graph it generates:
Since I am a Mac user who (until recently) didn't own a Windows PC, the above two items necessitated the purchase of my first Windows PC in over seven years! Turns out this was not as expensive a proposition as it sounds.