BLACK+DECKER Thermal Leak Detector (TLD100)

First off, this is a thermal leak detector, not a thermal thermometer. As a thermal leak detector, it does exactly what it says it does.First, you set your reference temperature. You do this by first deciding what variance from your reference temperature you want to measure [+/- 1, 5 or 10 degrees F or .5, 3 or 5.5 degrees C]. Then point the device at your reference point, normally an interior wall. Press the button which locks in your reference temperature. Then simply point the device at whatever area of the structure you want to test. The detector will both display the scan temp, to a tenth of a degree, and the reference temp. In addition, the light beam will show green if +/- the variance you set, blue if below your variance [colder] or red if above your variance temp [hot]. For example, reference temperature is 68F. Point at an outside window frame on a cold day. If cold air is leaking in, and your variance is +/- 5F, then if the leaking air is colder than 63F [68F less 5F], you'll see a blue light projected on the window frame. Now point the device at an electrical device of some sort. If the device is "hot", say 74F or higher [68F + 5F] the light will shine red on the object. This color feature is great when you are testing because you don't have to constantly be looking at the scan temp on the readout, though it's there if you want it. It will work on the glass of windows but you won't see the light except at night.Overall, in my opinion, a great buy at a great price for the average user. I am not familiar with any other thermal leak detectors, but for the average homeowner, a great addition to one's tester box.

I've used thermal guns before but this 3 color light indicator is way cool. It makes checking temp delta's very quick. With the old gun (with laser pointer), it was, point at the area you wanted to test and then look at the meter, repoint the meter to a new location and look at the meter again. With this TLD100, it was just move the light around the area you are checking and the only time you have to actually look at the meter is when the color changes. It completely eliminates this looking back and forth at the target, then the meter, then the target, then the meter,...A comparison would be the difference between using a box end wrench or a rachet wrench to remove bolts. It makes the process much simpler and faster.I bought my unit at the wrong time of year when the outside temp was, at maximum, only 30 degrees different then the inside temp so even though I found some leaks, they were minor. My house is about 40 years old and since I bought it a few years ago, I installed storm doors and had added insulation to the attic. All the windows and doors are relatively new and from what I can tell, this house is relatively tight. Even though I didn't find any major problems, it's gives a certain peace of mind to know that everything is okay. This summer when the temps hit the 90's, I'll retest.The bottom line is that for home use and price, this is a very good meter. As some posters have pointed out, there are more accurate meters available and IR camera's that have far more versitility, but for what they cost, it would be much cheaper to not fix your leaks and just pay for the extra energy costs.Addendum:I've owned this product for a while now. When I first got it, it took under a minute to figure out how to use it. The concept behind it is very simple and very well done. At first, to my chagrin, my house seemed very tight and I found no hot or cold spots of any significance. I almost felt like I wasted my money, but there is a certain amount of consolation knowing that everything is in order.Recently, I bought a whole house fan, but my attic access was too small to get it into the attic, so I enlarged the opening. I knew that I would have to insulate the cover to the new opening, but before I got around to it I used this product to see what to expect. It was a warm day and I had the air on at about 77 degrees. When I pointed the meter at the new attic cover, it was reading almost 100 degrees. What that meant was that I had a radiating surface of about 7 square feet at 23 degrees over the interior of the house temperature. Looking toward the future when the winter would come, I could have a temperature differential of over 100 degrees during very cold days. In the summer when the temperature gets into the mid 90's or more, my attic temp exceeds 140 degrees. This would give me a temperature differential of over 65 degrees.I figure that this knowledge alone would pay for the meter in short order.Anyway, I really like having this meter and contrary to what some posters have said about it's accuracy, it's the delta (temp difference) that is the most important thing to be concerned about in this case.

For the price, this leak detector is an excellent tool for a DIYer looking to improve insulation in their house.The device is basically an infrared thermometer. The difference with the leak detector is that it compares temperatures, and lights up the wall in different colors based on the comparison.Here's how it works:1 - point the detector at a wall that you know is insulated, and turn on the detector2- upon turning on, the detector measures the temperature of the wall, and remembers that temperature3- now you move around the room/house, pointing at different parts of the wall, near windows, doors, etc.4- the detector constantly reads temperature and compares to that initial wall reading5- A green colored spot is projected onto the wall where you are pointing the detector.... if the temperature differs by a certain amount, the spot turns blue (colder) or red (hotter).6- a 3-position switch lets you decide whether you want the spot to change color for 1 degree F difference, 5 degrees F difference, or 10 degrees F.This detector did not just point out the obvious problem spots (like door jams, near windows). You really don't need a detector to figure out those spots. This detector highlighted large differences on the *same wall,* where it turned out that insulation was lacking or had fallen off.I deducted one star for the accuracy of the temperature reading. I have another infrared thermometer which I know to be accurate, so I compared readings. This leak detector was a few degrees off from the other detector. That said, this leak detector still calculated the correct difference in temperature, which is its main functionality. If you want a very accurate temperature reading, get a dedicated thermometer.Others have commented on the box size - it seemed pretty appropriately packaged to me. The detector is a rather odd shape, so the box had a fair amount of empty spaces. Nevertheless, the device is packaged well.Build quality is fine. The whole device is plastic, with a battery door that pops open in the grip. For the price, I have zero complaints with build quality.In summary, this device is handy and serves its intended purpose very well.