I have looked the community over and my search skills may be sub par but I can't find this info if already stated so please look over me. I have an exhaust fan and light on the same switch. The exhaust fan is wired in at the light. For a couple different reasons I want to keep the switch the way it is and use a smart bulb in the light. Putting a cover o nthe switch and leaving it on at all times. However, I would like to install a relay between the light and the exhaust fan to kick the exhaust fan on and off via a contact sensor on the door. Do you guys have a suggestion on a good relay to use and wiring for such relay?
There are various in-wall modules that will probably do the task.
This is a visual example of the form factor:
I'm not sure I'd recommend Enerwave, but I've seen then from Zooz and Shelly (wifi), and are supported in Hubitat. Door contact sensors are plentiful and most of mine are Aeotec Recessed Door Sensors, which get buried into the doors.
You'd disassemble your light/fan enough to fit the module in and gain access to the wiring. Couple of Wago connectors later and you should be golden.
I use a Zen51 for my bath fan, but it doesn't have a light to deal with. It's corresponding wall switch doesn't use any line power (long story), so I just took the switch out (blank-plated that wall box) and wired the Z51 up in the fan itself.
I had to tease the necessary wires out of the fan's junction box (not a ton of fun), but I was able to cleanly tuck the Z51 up in the housing such that it gets good reception without being noticeable if you look up in there. It's been completely reliable for a few years now.
I have a basement vent (used to have a large aquarium setup down there) that is a repurposed bathroom fan with lights. I have a Z-Wave double relay (much like the Zooz 52LR... but this was installed when original Z-Wave was the only option). It still allows for switches but you do not have to have them. So I can turn the light on when the basement door is opened and the fan could automatically turn on when a humidity sensor got too high.
Not really in use anymore... once I shut down the aquarium (and I have not bothered to replace the door sensor's batteries lately)... but it is still there and does respond to the Hubitat when I check it. It is now ~10 years old (pre-Hubitat for me).
You could add a Zen51 at the fan and a zen30 in the wall. The zen30 would have the dimmer wired to the light and nothing wired to the relay. The dimmer would then be set to “smart build mode”.
You can use rule machine or basic rules to trigger the Zen51 when the zen30 relay button is pushed.
Thank you very much. May I ask why you may not recommend this relay?
Thank you. Even though different it is still very similar to my setup. The light fixture will always have power as I am not going to be turning it off so it will be similar to the fan being direct wired. I looked the Zooz up last night. Is the wiring pretty simple. I know my way around electrical but I like to understand the setup before I tackle it.
Thank you. That is something to keep in mind. I have only been at this since April so I am still learning a lot of things.
Thank you. I never thought about using a double relay setup. One of the problems I have though is my house was built in 1985 and it just runs a switch loop to my switches. There is no neutral in the switch boxes. If I modified the switch setup in any way it would have to be no neutral required.
Didn't last. The first lasted just under a year, the 2nd was7 months. I suspected that they didn't have a EMF protection component across the relay contacts. It would be a convenient way to save money and then just put words on a paper saying to not use it for motors. Fans are motors and I'm on year 3 of the Qubino Dual relay device.
Unfortunately, that exact type thing happens across a lot of industries. Do you have a model number or part number for the Qubino dual relay you use?
https://www.amazon.com/QUBINO-Flush-ZMNHBD3-Z-Wave-relays/dp/B06XFC2V6M
https://www.amazon.com/Fibaro-FGS-223-ZW5-US-Double/dp/B01LZPD441
Qubino was bought by Shelly so there may well be a Shelly branded version of the Qubino.
There are other functions produced for that same form factor, including single dry contact relays and single dimmers.
Indeed, Shelly is co-marketing the dual relay:
https://www.amazon.com/Shelly-2-Channel-Automation-Compatibility-Installation/dp/B0DF7HP6ST
I had been looking at the Shelly. Do you know if there is a community driver for the z wave Shelly? I don't see a native one but I could be over looking it.
Qubino 2 relay is the driver I use and I have to believe it’s the qubino in a Shelly case
Thank you. I appreciate everyone's help.
