Dash Air Conditioning 2016 Vista LX

[poodleman]

My Chassis AC is no delivering cold air ?
Fan runs and blows air, heater work

 

[RayIN]

Look "under the hood" and locate the mfgr.s name. Then we can help.
This is a generic dash-air service manual: https://btrac.com/wp-content/uploads/2025/04/Service-Manual-Revision-1-2011.pdf

 

[Morich]

We don't have the info needed on which floorplan of that year and model of RV, so we are limited in looking up much info as it is filed year model and floorplan.
With nine different RV in that group, our odds of hitting the correct one are pretty slim!
But much of the problem may also be more a chassis question than RV as the RV is built on a stripped chassis. So much of this area can be somewhat on the border whether you need chassis info or RV info, depending on who added which exact parts.

Parts Catalog

Can you spot which RV you have as that can let us take a look at how it might be built and sometimes make better suggestions?

One item that is semi easy to check and can be verified by a close look, is how the controls may be working.
The dash controls are often airline from that control head to other places where various valves and flaps open and close for the different heat/cool/defrost changes.
One thing to check is what happens when the controls are changed from heat to cool, etc. Various types use different controls so this is just a possible thing to check but it is somewhat common for the rubber tubing that uses engine vacuum to move things gets brittle and leaks!
One thing that can happen is when the valve that cuts off hot water flowing though the heater stops closing. It often is easy to spot as it set in a hose between the engine and the heater and has a vac line on it. If the valve to cut off hot water doesn't close, it may simply overwhelm the AC trying to cool the air! The AC may be cooling but you can't tell it because there is so much hot air going inside!
One low cost/low tech idea is to find that valve and see if it moves when the controls are changed from heat to cool!
It might be worth the time to take a look under the hood and verify this type vale is moving?
Almost certainly not the one you have as there are hundreds but this might be a general idea to look at something simple like leaking vacuum lines?

Good luck on the chase. I like to check the cheap, easy fixes first before diving into the tough stuff that I can't see!

 

[wyocamper-WO]

My A/C compressor died last year on our way to TRNP, same type symptoms. Only it was 104º in ND that day. Good times. I would take it to a shop and pay for an A/C diag. Mine tested as equal pressure on high/low sides, the shop said compressor failure on the Ford is fairly common.

 

[powercat_ras]

The 2016 Vista LX is built on Ford F53 and the AC Compressor is part of the Ford chassis build. Winnebago adds the rest of the AC system, using a 3rd party system. In 2015 Vistas it was Evans-Tempcon. It may be different in your model year. If you look on the Winnebago website you can see and download manuals for the AC system. You may have to view the RV drawings to see which system you have, unless it is part of the supplemental manuals.

You can have someone listen in front and see if they hear the AC Compressor Clutch engage when you turn the climate control from OFF to AC MAX. If not then chances are your system has lost refrigerant. There is a pressure sensor that will prevent the clutch from engaging if the refrigerant pressure is lower than required that protects the compressor from damage that would take place if it ran without the refrigerant/lube in the system.

On my 2015 the Winnebago factory mis-routed the AC lines coming off the back of the AC Compressor so that one rubbed against the tip of a self drilling fastener behind the compressor and after several years it caused the line to have a leak that caused loss of refrigerant. Fix was line replacement and refrigerant/AC system lube recharge on my 2015 Vista.

The AC system has standard test / fill ports so you can have the system checked to see if it has refrigerant at the correct level. If not then the reason for the problem has to be found and fixed. If just a leak chances are the compressor is still good and it won't be too painful cost wise and time wise to get fixed.

 

[moabdds]

I had the same problem with my 2016 Itasca Sunstar LX. I took it to an automotive AC shop (my local Winnebago dealer wouldn't even look at it). They found that it was low on refrigerant because the seals had dried out and shrunk. $700 later, it was fixed. They told me to run the AC periodically, even in winter or while stored, to keep the seals lubricated so it wouldn't happen again. Once a month now, I crank up my generator and let it run for 30 minutes to keep the carburetor from gunking up (again) while running the roof AC to provide a load and keep it functioning, and run my dash AC for 15 minutes to lube the seals. Monthly preventive maintenance. So far, so good.

 

[RAJTAJ]

Fact: the components on the Ford supplied A/C units just simply suck. Very common problem for RVers.

All of the above is very good advice, but unless I missed it I didn't see anyone mentioning to be sure to have your schrader valves on the A/C system checked.

Our system had most of the major components changed twice under warranty. When it seemingly crapped out a 3rd time, no longer under warranty, we found an excellent RV shop that specialized in A/C work and they found that 2 schrader valves had gone bad. Very minor repair compared to a system rebuild, and it fixed the problem completely; works better than ever now.