I want to replace two 3 way switches with two 3 way dimmers but I can't get it to work correctly. The house is old and wiring is circumspect at best, but the circuit works correctly with a dimmer and a switch, so why won't it work with two dimmers?

 

I think that you have already figured out that you can only have a dimmer at 1 location.

 

The only way to have a dimmer 3-way that I have found is made by Lutron it is called the smart dimmer and costs around $30 each. They work great However they are not wired the same as a regular 3-way, but they do use the existing wiring and are easy to install if you folow the instructions provided. The system uses a master unit for the primary switch then each additional switch uses a (slave )unit and can be turned on and off and dimmed from all locations. Sorry if this sounds like a commercial for them but I had the same problem and the one- switch deal drove me nuts for a long time


Hope this helps