Shelly Dimmer 2 - Rewiring for two way switches

  • Hello guys,

    I would like to install the Shelly Dimmer 2 (without neutral) to control a light that is also currently controlled by two way switches.

    My configuration is exactly the same as described in another post in this forum (source: Shelly Dimmer 2 - Wiring with two way switches and without neutral ). Below the related schema:


    However, my situation is slightly different because of the following restrictions:

    1. I need to place the Shelly in the box where Switch1 is located (Switch1 and Switch2 are indeed located in two different boxes), since unfortunately there is not enough space in the first box to fit the Shelly
    2. I cannot pull any other wire between the two boxes. This means that I have somehow to deal only with the two wires that are currently in the boxes
    3. There is no live wire in the box where Switch2 is located

    Considering the restrictions above, is there a way to install the Shelly Dimmer 2 (without neutral) in order to work with both switches and without pulling any other wire? I was thinking about rewiring the two wires that are now connecting the two switches in a different way, although I'm unsure about how to do it.

    Any help is really appreciated.

    Thanks a lot in advance! :)

  • Hello. When you have this configuration at the switch boxes, there must be an additional wiring box, where the supply, switch lines and lamp line come together. Can you place the Shelly Dimmer 2 there?

  • Hello,

    Thanks for your feedback. There is indeed an additional wiring box between the two switches, but unfortunately it is not accessible from outside (and this is the main reason why I'm trying to find a way to connect the Shelly Dimmer 2 using only the wires already available beside the switches). Such box is placed behind a lot of furniture in the kitchen and it is not possible to access it unless I move all the furniture, but it is not really feasible at the moment... Likely the person who performed the first electrical wiring in the house did quite a bad job (some electrical boxes not accessible, some wiring performed using wrong colors, etc.), but the house was already built and furnished this way when I started living there.

    As far as I know in this situation I only have to deal with the wires I have available beside the switches since I cannot pull other ones, is it correct? If so is there a way to connect the Shelly Dimmer 2 in the scenario explained above? If there is a way to access these "hidden" boxes instead I'm really interested in how I can do that, since it will ease a lot the connections with the wires. ;-)

    Thanks again!

  • Well, just one possibility in my view, like described in the other thread:

    - enlarge the box of switch 2, make it deeper, cut out parts of the wall, place the dimmer there

    - replace the switches by pushbutton type (momentary switches, normally open NO)

    - one of the corresponding lines is used to feed L from box 1 to box 2

    - the other corresponding line is used as switching line to SW1 input

    - parallel configuration of both pushbuttons.