I have a Spacepak ESP-2430G high velocity heating and air system (electric). My thermostat was knocked off the wall and broken leaving the wiring exposed. I am trying to install an Ecobee lite where the old stat was, and I cannot get it to even turn on. I found the C terminal on the air handler and hooked a wire that was unused (brown wire) to that terminal since Ecobee needs a C wire, and it still won't power. I am using the diagram for wiring listed in the manual:

There is a red light blinking on the air handler control panel (D2) Fault, but it blinked previously, and the old stat worked as it was a clogged condensation tube, and when cleared it went away. The pipe is now clear, but the light is back. Anyone else had this issue? The HVAC company I had come to fix the original issue accidentally broke the old stat, and then couldn't fit in the tiny crawl space to get to the air handler, so he left me with no heat (he wasn't a jerk about it, he just couldn't fit in the crawl space).