Originally Posted by jimkitch
I just left Forest City after having some work done on my new 2021 Adventurer 35F. One of the issues was the dash A/C pushing hot air at any RPM above 2500. It turns out when Ford switched over to the new 7.3l V-8 they also changed the design of the three port water valve. The high pressure hose and the low pressure hose are in the reverse positions as compared to the V-10 engine. This is a know problem to Winnebago. When I called the service line while at Forest City and spoke to a tech, he said "oh yea the low pressure and high pressure hoses are reversed. Tell them to switch the hoses while you are here." I spoke with the tech servicing my RV and he said he knew about the issue and that since the RV had been driven for a while he would change the valve as well because the hoses being reversed most likely has damaged the valve. He did this and we left for OKC the next day. The dash A/C pushed cold air the whole trip home, no matter the load on the engine. My suggestion is, if you own a Winnebago with the new V-8 engine and you have hot air coming out of the dash instead of cold, call Winnebago and schedule an appointment at a dealer or in Forest City to have the hoses connected correctly.
Yep, multiple threads here and on the WBGO forum about this issue. WBGO and other mfg's. were in denial to begin with. Swapping hoses worked for me. I just wish I'd known about this easy fix before taking a 5,000 mile trip out west to NV and UT!
I figured I'd have to leave it at a dealer for warranty, as many others have, for weeks.