I found a leak just below the circulating pump and replaced a small section of the tube. Now I'm getting the "high limit" fault probably from air in the system. I read in other posts that running the pump would take care of the issue, but so far, after allowing the fault to occur and then not resetting and allowing the pump to run hasn't bled the air out of the system. Now I'm guessing the reservoir in the nose of the RV is the coolant supply/overflow. I left the cap off during this procedure. Any suggestions? I just want to get going but keeping finding issues. Unfortunately we are leaving from Ontario and we might be in cool weather fo the first couple of days and I want this working. Prior to the leak the system was working great!!!Thanks. Eric