House Fan Timer/3-way Switch Wiring Help

Hardware
1

Hey Community,
I am not normally one to request help on matter like this but I am at a total loss. I have already replaced half of the switches in my home with Z-Wave Dimmers and Switches and I have personally installed breakers and other 120V wiring in my previous house.

Well, I have recently moved into a new build home and have found that the electrician took a lot of shortcuts. I was not permitted to review or add/change the electrical until I took ownership of the home but by that time the dry wall was in place and I was left painted wires and way too many 3-way switches.

My issue is that I am trying to replace a switch for my whole house fan with a Z-Wave Switch. Attached to this switch is a radial timer which allows me to set On/Off periods by flipping the dip switches to the inner or outer ring of the timer. I am familiar with 3-way Switching but this set up makes me want to take a hammer to the wall to understand what was done.

Very early on in this house we found that the wiring to the timer was originally done incorrectly. The dial would turn but the fan would not turn on at all.

Below is an image of my setup, the lower switch appears to be a 3-way while the timer on top is using a red runner. As I mentioned previously I am at a total loss. I have not been able to find any diagrams that would show how this is wired from the load to the fan.

Each box has a twisted ground with wire nuts.
If anyone could figure out this puzzle and maybe explain this in a wiring diagram I would be extremely grateful.

Current description of operation:
Timer has Off/On/Auto setting. Auto allows the timer’s setting to function.
Switch was installed with Red/Black wires on TOP. In this orientation UP position manually turned ON the fan (picture is showing the OFF state).
A Ground was only connected to the Switch, not the Timer.

Timer’s Single Gang has 3 Whites nutted, and 3 Black nutted. The only red connects to the timer.
Switches Single Gang has a White pair nutted, and both infeeding blacks go into switch along with the red.

2448×3264 1.9 MB

2

Thanks for all of the wonderful input folks.

I figured it out. Electrician used a 3-way wire to pass though the switches to make each switch in parallel, not 3-way.

To Connect my Z-Wave switch I had to make the upper Black be a pass through load to let the switch operate. Then the Blue-to-Red (Blue from z-wave switch is Load-Out) into the top gang box. The timer’s red connected to the Red (in gang) and out to the Fan (load). All other blacks tied, all blacks tied in switch gang.

Now,

3

Why don’t you ditch the timer and use HA to control the schedule? With a simple temp sensor you could automate it nicely along with presence detection.

4

Thought of that. I would rather use the basic timer as a minimum fresh air into the home and use the z-wave for presence and outside air equilibrium based on temperature.