Digital Thermometer Dual LED Display Fahrenheit to Centigrade Adjustable DC 4-28V -67~+248℉/-55～+120℃ High Accuracy Temperature Gauge Sensor with 2 Waterproof NTC Probes K-017

They're not forthcoming with instructions on how to adjust/calibrated each channel but it involves holding down the micro pushbutton on the PCB until you reach the menu. To reach the menu, hold down the button for 2~3 seconds... •Short clicks scroll thru the parameter selection, press and hold to adjust the parameter •When the parameter is being adjusted by holding the button down, it will increment. Release the button for a second and hold it down again to decrement. It's a little confusing but it really does work! The method described is something you really have to do yourself - until you 'get it' To make life easier, I desoldered the surface mount pushbutton and added a normally open pushbutton on a 8" length of wire...I put the works (batteries, switch & display in an appropriate enclosure) I fabricated a Subcooling & Superheat measurement instrument from this device...the RED colored display measures/displays the temperature of the high pressure/liquid line. The BLUE colored display measures/displays the temperature of the low pressure/suction line. By use of a custom made circular split bushing which replaces the jaws of a plastic spring clamp (to hold the thermistors on each of the aforementioned lines) I'm able to calculate subcooling & superheat parameters whilst adding refrigerant to an HVAC system. Powered by 2x 18650 batteries - this thing works great. It's accurate on a 2 point calibration - if you take the time to do it. I think it's an excellent gauge. Great price point - love the 2 different colors on the display. This is the way to get a good thermometer gauge for a great price. I'm going to purchase several more since these work so well. Two thumbs up!

Very compact display which is what I wanted. Haven't calibrated to my Fluke thermocouple yet but temps seem to stay consistent. The blue display does not light well at lower end of voltage range but comes to life at 12/24vdc. Will likely need to calibrate after install as I will add ~20' of wire to the thermistors. Will also be in thermowells as your sensor should never contact the process material.

Works great to monitor the temperature difference across my AC coil. Very satisfied with its operation.

Was working like a Champ, then reconnected power wires and unit switched to C ! Trying over and over to menu, c/f, short push to show F; then after few seconds flips back to C and Celsuis displayed again. Tried factory to, yes and no, always back to C . Help.

Very nice dual zone wired remote thermometer. I love its small size and bright digital displays. The unit is really sensitive and responsive and its accuracy was spot-on for me. The best feature of this thermometer (in addition to its dual displays) is the fact you can change between F and C display units and the measured temperatures can be adjusted to compensate for any error or temperature differential you might need. Pay attention that this thermometer uses NTC probes and is NOT K-type thermocouple compatible. I made this mistake thinking I could use this module with existing thermocouples I had, but I ended up needing to change out the entire system. Luckily it wasn't difficult for me and I actually like the performance of the NTC probes even better.

I bought two of these, one for each of my two aquariums. I temporarily installed them and put one probe in the left side of the tank the other probe in the right side. I let them sit for about three or four weeks and the temperatures for each probe were usually within a 10th of a degree with of each other so I thought they would be just fine. I then took the time to chisel out a hole in the cabinet to recess the gauge, so it would look nice and reinstalled the probes on each end of the tank. all is good for about two months. Then one probe started getting about 5/10 of a degree off and within three months of that the temperature is varied at least 20° from each other, just being inside the same aquarium tank one on the left side one on the right side. I know they can be programmed and be reset and recalibrated manually. But a 20° variance that needs correcting every 3 months is unacceptable. I wouldn’t recommend these to anyone that needs to keep track of the temperature of a fish tank.

Great product. Accurate and easy to read. I use them as they are, with a 9 volt battery box. Now I get to hear a joke from Jeff, for reviewing a bunch of products.

Fonctionne très bien

Easy to read and very bright. Standard size that fits the opening of a voltmeter I don't need anymore. I use it for indoor/outdoor temp readings in my off-grid cabin. The button on the back has a few options on it. I wish I knew what they were. I love how I can switch it to Celsius for the Canadians.

Not having such great luck with this temp guage. Seems to periodically start flashing, goes blank, and then works fine again. Im using it to read cylinder head temperature on a Buell motorcycle. I just attached the probes with epoxy and it works very well. Until the flashing begins. I will be investigating the wiring this weekend to see if that may be an issue. I will update once I'm certain of what's causing the issue.

Used unit to measure Hydraulic fluid temperature before and after the cooler. Both probes read the same temp within .2 of a degree. Longer power wires would be nice.