I have a Coleman Evcon EB23B in my Manufactured Home. I started up this cooling season just fine ran twice and now nothing either inside or on the outside unit. I asked my normal service repairman about it and he said try the Thermostat. So I got a new one and installed and this changed nothing. Any Ideas?

Did you check to see if you have 24-28 volts from the control transformer? That makes no sense at all to just change a part without checking things out with a meter first. Check your control transformer first, then if you have voltage at the transformer you need to check any inline fuses and there also is a door switch on the access cover on the return that turns off control power when the door is open or not closed tightly to prevent carbon monoxide from being sucked into the return air. Frequently this switch gets out of adjustment or goes bad. Most are micro-switches with a 2" strip of metal that contacts the cover and that strip can get bent in and then will not work until bent out so door will close switch. You spent money for nothing where for the same money you could have purchased a meter and then knew what the problem is.