karenandcollins Report post Posted September 7, 2010 We have 2 AC units in our 40' motorhome. The front one practically freezes us out, unless I set the temp rather high. The back one in the bedroom seems to start out cool but gets warmer as it's run. At the beginning of the summer, even in high temps it worked great at 74 or 75, now, it's much cooler & I'm running it at 71-73 & by morning its not all that cool. I've cleaned the filters & looked inside as much as I can. Any other thoughts. Thanks. Share this post Link to post Share on other sites
wolfe10 Report post Posted September 7, 2010 If this is a ducted system, make sure the inlet/ouitlet are properly separated. If not, the cold air is recirculated through the A/C and leads to premature freeze-up. Some A/C units have a freeze up sensor, others do not. Also make sure air volume out the ducts/vents is strong. If not, it may be that a duct is not properly connected. And when this occurs, if you put the A/C to fan only, does that speed up the recovery time until you can turn it back to cool and get acceptable cooling. If so, another sign that it is freezing up. If no problem with above, next thing to do is clean the EVAPORATOR. The air filters on these units are not nearly as effective as those on house systems. The water on the evaporator attracts and holds dirt (and allows mold to grow). So, particularly in humid areas where the evaporator stays wet much of the time, cleaning the evaporator is almost a routing maintenance item. This is done from the roof and can vary from reasonably easy to "lots of small screws to remove" depending on brand and model. Brett Share this post Link to post Share on other sites
