I want to change the timeswitch connected to a Vaillant Turbomax. The existing timeswitch is external to the boiler and has a potential free contact connected across terminals 3 & 4 of the boiler. My new timeswitch only has a switched live output.
So, do I connect the new timeswitch switched live to terminal 3, or 4?
Or is the potential free switch used because the Turbomax uses some obscure non mains voltage for its control circuit? (I assume not as the installation instructions show a thermostat with an accelerator connected to a neutral which wouldn't work with a low voltage)
So, do I connect the new timeswitch switched live to terminal 3, or 4?
Or is the potential free switch used because the Turbomax uses some obscure non mains voltage for its control circuit? (I assume not as the installation instructions show a thermostat with an accelerator connected to a neutral which wouldn't work with a low voltage)