Using this receiver in conjunction with the Venstar Wireless Indoor/Outdoor Remote Temperature Sensor (Item# 30408), I was easily able to monitor the outdoor temperature and display it on the Venstar T1800 thermostat. The receiver easily fit inside the junction box behind the thermostat. And the LED indicators confirmed receiving the signal(s) from each wireless transmitter.

Works well. Bad instructions.

Instructions are basically non existant, so here's my experience... this is also why I subtracted 1 star The receiver is placed behind the thermostat in the wall and averages all the incoming wireless thermostat signals that are set on the same channel up to 8. Looks like you could have up to 8 receivers if you had that many thermostats, based on the number of channels available. The receiver then sends the average signal to the thermostat as EITHER an outdoor signal if wired to the RS2 channel or an indoor signal if wired to RS1. The receiver does have 3 LED lights to tell you if it is receiving signals from at least the first three wireless thermostats, but I never checked those as it was already behind the wall if it didn't work I guess I could have pulled it and left it dangling to use the LEDs for trouble shooting. According to the manual, the batteries in the wireless thermostats sold separately last up to 2 years when set to check temp every 5 minutes. Lithium batteries can be used to place thermostats outdoors in cold climates. Some notes: The T1700 DOES NOT HAVE AN RS1 jack... so while this receiver will work with that unit, it will only check outdoor temp. The T1900, when using RS1, can average its own thermostat with the wireless ones, or can use the wireless signals. It cannot use both independently. It looks like it can accomodate 2 receivers, so you could have wireless indoor and outdoor signals. If you installed your thermostat, installing this is easy at least, once you figure out the terrible directions