[francherie]

    As we continue to get to know our newly adopted coach we realize more each day how much learning we still have ahead! We have been working lately on the vast heating systems and trying to understand what thermostat controls what, etc. Thankfully we have all of the original blueprints and wiring schematics, but I thought perhaps someone would know this answer off the top of their head. 
Recently we have been hearing a fan coming on in the front passenger ceiling above the soffit. The thermostat in that front area has been off both times. Fran checked it out this afternoon and it seems to be drawing air rather than blowing. It comes on and shuts off by itself.  What is this and what is controlling it?