Honeywell2 Pack RedLINK 3.0 Indoor Sensor C7189R2002-2

If your HVAC system has a Honeywell T9 or T10 thermostat (or you plan to upgrade to a new thermostat), these small RedLink sensors are a great addition to ensure that room temperatures are properly maintained when a room is occupied. Basically, the sensor allows creation of a pseudo zone for a single HVAC system. Simply mount the included clip on the wall using either the included screw or 3M adhesive strip and "click" the sensor onto the clip. Add the sensor to the system using the menu on the T9 or T10 thermostat. There's one minor thing to know - for the thermostat to automatically switch between sensors, a sensor needs to be added to the room that has the thermostat installed. Thus, depending upon the number of rooms that are monitored by a RedLink sensor, one additional sensor is required. Alternatively, each sensor can be selected manually to be monitored and deselected when the main thermostat needs to control the temperature setting. Save yourself some frustration and add a sensor to the room with the main thermostat installed. It will be good money spent!! Overall, great sensor for the money.

I bought these to install in additional rooms to work with the T10 and they are working very well. The farthest one is maybe 40 feet away from the T10 and is working fine. I have not really used the "activity" setting on the T10, where the sensor uses its motion detector to tell the T10 which rooms are occupied, so I can't comment on that. I plan to use this functionality shortly, so I'll update this post.

I have four sensors near each other testing them in same room. The humidity not very accurate, from sensor to sensor varies by 8%.