Review on ThermoPro Bluetooth Hygrometer Thermometer Greenhouse by Sandy Johnson

freeze defrost cycle has become intermittent and I need a way to control it until I can count on it to work reliably. In short, it turned out to be an internal electrical connection that needed tightening after years of fatigue and metal oxidation, but the purpose of this review is to report on how this device performs in sub-zero temperatures . I simply attached this gauge with a magnet to the inner rear metal plate where the defrost heater is located, so every time it got hot I noticed a brief but noticeable rise in temperature (see diagram). I can report that this counter is doing something odd well below freezing. . The humidity jumps 20% at the end, so although my freezer humidity was actually below 30%, the meter read around 50%, so this meter is probably not at all suitable for outdoor use either. To protect the circuitry from the air in the freezer I covered all of the plastic case vents with a layer of tape as the spot I needed to record was near the vent - this worked well without affecting the meter. I'm happy to report that although the freezer is a Faraday box, the Bluetooth signal from this meter was able to penetrate tin and reach my cell phone 20 feet away. The fact that the meter also appears to give a battery status indicator is handy to know. I wish the app was a little smarter so we could automatically check the counter at certain intervals even when our phone is sleeping and set high low alert thresholds, but for what I paid here I'm just glad they have enough Saving records could be useful as a history between Bluetooth-connected downloads between the glucometer and my phone.