BN-LINKSmart WiFi Digital Temperature Controller Heating Cooling, Works with Alexa and Google Home. For Reptiles Aquarium Carboy Homebrew Breeding Fermenter Seed Germination °C/°F -40-176°F 15A/1875W

I've been using this product for a few years now and it is genuinely one of those rare products that is just uncompromisingly good. At the risk of sounding like a review robot, I want to elaborate on my experiences with this device and why it's been one of the best electronics I've bought from Amazon.To clarify, I have only ever used this device for controlling the temperature of my living space, not for any agricultural or misc purposes. Despite this, as someone who is a nut for home automation, this device serves its purpose perfectly.HEATING OUTLET, COOLING OUTLETThe device works by providing electricity to one of its two outlets based on user-defined conditions. These outlets are helpfully labeled "HEATING" and "COOLING". Having a single device that can control both a heating solution and a cooling solution is SIGNIFICANTLY more intuitive than having two separate systems, one for heating and one for cooling.A WIFI-FREE SOLUTIONMany similar devices are wifi-controlled. That can be a good thing if that product allows for more advanced setups like schedules, but in positions like mine where I live in University Housing (where IoT devices are not allowed to connect to the internet, only complete devices like Computers and Phones can) having an analog system has been ESSENTIAL. Being able to just plug the device in and push a few buttons instead of filing an application with the property holder to add a special exception for the device on the network is much more elegant.PERFECTLY ADEQUATE CONFIGURATION OPTIONSThe device has plenty of variables that can be used to create the exact behavior you want. Some highlights include:SU - "Set Unit" - The ideal temperature you would likeHd - "Heating Differential" - How many degrees colder than the Set Unit the temperature must be before the heat comes on.Cd - "Cooling Differential" - Home many degrees warmer than the Set Unit the temperature must be before the cooling comes on.PT - "Time Differential" - After the system reaches the SU, the system will wait for at least PT number of minutes before allowing any outputs to turn on.By mixing and matching Hd, Cd, and PT it is possible to create very specific behaviors. I will elaborate on this in the next section.GREAT FOR SPREADING OUT CYCLESOne way I use the device is to control my air portable conditioner. By default, my AC will turn on when the temperature drifts by more than ~1*F from the target. This can result in a lot of really short cycles that can be distracting. By configuring my device with a Cd of 3 and a PT of 4, I can make it so that my device runs for longer but less frequently. This is ideal given how jarring the transition in volume between idle and operating modes in portable air conditioners.DURABILITYThe device is extremely durable. My device has seen a fair bit of abuse and functions exactly how it did when I got it. I also appreciate how the cable that connects the device to the outlet is very thick, as this pretty much ensures any devices you plug into the outlets on the device will not be drawing too much power for thin cables to handle. My only consideration is the rather flimsy cable for the temperature probe. As long as you are gentle with it it will be fine but because its connector is a 90* angle it can sometimes be easy to bump it.That's all I've got for now. In a world where products are getting cheaper and flimsier, it's reassuring to see products that are durable and practical. No gimmicks, no risks, if you want to control a heating and cooling system through an external analog device I really think this is the device for you.

This curious little device is easy to set up if you read the instructions, but mine has a quirk. I'm using it for heating, controlling 2 big 2'x4' seedling heat mats in 2 cold frames, and it always stops heating 5ºF too early.To control the power for heating, you tell it what temperature you want, the Set Value or SV. Then you tell it how many degrees below that value it should wait until it sends power to your heater (in my case, a heat mat). This second number is the Hd, which I assume stands for something like Heating Differential.I'm working in Fahrenheit. I set SV to 58, and Hd to 13. I monitor the temperature where I've placed the BN-LINK's temperature probe. It lets the temperature fall to 45F (13 degrees below 58), then turns on power to the heat mats just like it's supposed to. It then heats to 53F, but instead of continuing to heat until it hits my set value of 58, it stops. The temperature goes down pretty steeply until it hits 45F, then it heats back up to 53 again and stops.I set SV to 60, and Hd to 10. Now when the temp falls to 50F, it correctly turns on the heater, but as soon as the temp hits 55, it stops heating.It's clear there's an easy workaround. To get the behavior I want in the second case, I need to set SV to 65, and Hd to 15. And the thing is so far dead reliable, so I'm giving it 5 stars.

It's a good device but the instructions could definitely of been written better. Also so everyone knows as well. It takes about 3-5 minutes for the cooling device to turn on if the temperature gets too hot. So say you want it at 95 and it goes past, the heating device will shut off buuut the cooling device will take its time to turn on. If the temperature proceeds to increase the cooling device turns on but if it goes to 96 the heat will shut off and it will wait to see if it will decrease before turning the cooling device on.Re writing my review, its been 3 weeks now and I have to say I'm annoyed. Don't use this for a brooder. It had me up at 3 in the morning beeping and the problem is, i set the dang thing to keep the brooder warm at around 85-88 but what kind of sense does that make when the HEATING DEVICE TURNS OFF BELOW 85 😂 THIS DEVICE IS A JOKE. Plus good luck when it comes to not getting the baby chicks to lay on the themometer piece. I tried taping plus many other ways and they will still manage to lay on it and throw the heat scales off. I wouldn't trust your baby chicks life with this themometer. It let my baby chicks freeze. They were okay 😊 but no thanks to that themometer. OH AND WORST OF ALL. I try to call the company's number on the packaging to try and figure things out more with it and they refuse to answer actually I get a voicemail every time. This whole company is trash.