Currently there is a ventilation switch on the wall, which has 14/2 leading to a relay which will turn on my furnace and newly installed HRV. It also turns on the bathroom fan in the nearby bathroom.
However the bathroom fan switch ONLY turns on the bathroom fan on and off. And again the furnace fan switch will turn on the 'furnace' (again via relays etc) and the bathroom fan
I will attach a photo I drew and some explanation;
- Power comes into bathroom junction box
- splits via marrett to lower terminal on 2 way fan switch and to black wire on 14/3 wire to furnace fan switch
- black 14/3 wire (energized) goes to BOTH BLACK terminals on 4 way switch
- Red wire from 14/3 goes on upper brass terminal of 4 way switch to the load wire of the bathroom fan switch (this is key)
- Black wire on 14/2 wire to furnace goes from lower brass terminal on 4 way switch
So the interesting thing here which I have never seen before is my 4th point above, where if you look at my diagram, the red wire on the 14/3 is connected to the load wire just above the 2 way bathroom fan switch. meaning current can go down red wire from furnace switch to the bath fan and bypass the 2 way switch. However when the 2 way switch is operated (bathroom fan turned on) and current is sent down the red wire to the 4 way, the 4 way switch ignors this and does not trigger the furnace fan.
this picture shows the bathroom fan wiring
these show the furnace switch, note the 14/3 from bathroom is on the left and the 14/2 to furnace is on the right..
I would like to replace this switch with a timer switch, which i purchased a three way timer switch; Lutron MA-T51MN-WH
And i would like it to behave exactly how the previous switch worked, that is the bathroom switch only controls bathroom fan but the timer switch will turn on both
I tried installing the new three way timer and in most cases behaves as a three way, where if the bathroom fan is turned on/off while the furnace fan switch is on, the red wire becomes un-energized and furnace fan turns off. As well the furnace fan switch I believe did not turn on the bathroom fan, though I suspect this is because the bathroom is not a 3 way.
I know this is a long shot and it sucks because there is no 4 way timer switches on the market. But I am hoping if I swap the bathroom fan switch out with another 3 way (or 4 way???), there is the possibility of recreating what I currently have... Basically my question is;
how can I switch my ventilation switch to a timer switch which at best could be a 3way
edit: I realize I am an idiot for assuming it was a 4 way switch. its a dual pole switch.