winnebage 2016 View airxcel 47000 icing up

If you have a wall tstat, ALL RVP AC units have a freeze sensor that will prevent icing in any condition. So, either the freeze sensor is NOT installed in the evaporator or it is defective. If LD replaced the unit because of this, the Tech was an idiot. I doubt RVP paid for the replacement. You MUST get Authorization from RVP before replacing an upper unit and they would have advised to check the freeze sensor system, as this system does NOT come with a new upper unit. Part Changers rarely fix problems.Doug

Greetings from a fellow Floridian. As fellow Floridian, I can tell you that RV a/c is VERY likely to frost up/ice up on LOW in our humidity. You need as much air flow across the cooling coil as you can get, to get condensation out of the fins before it can freeze. If you have a good-running a/c, the cold air it discharges into the coach might be 50-60 degrees, but part of the coil could be below freezing. If frost/ice forms, it blocks air flow and also insulates that are of the coil. That makes it easier for more frost to form - it spreads! After awhile the freeze sensor finds out and shuts your compressor down, allowing time to thaw.
Your a/c could have been OK all along, or the freeze sensor could be bad or installed wrong. But even if it all good, hot humid FL summer requires HIGH FAN.

j-d wrote:
Greetings from a fellow Floridian. As fellow Floridian, I can tell you that RV a/c is VERY likely to frost up/ice up on LOW in our humidity. You need as much air flow across the cooling coil as you can get, to get condensation out of the fins before it can freeze. If you have a good-running a/c, the cold air it discharges into the coach might be 50-60 degrees, but part of the coil could be below freezing. If frost/ice forms, it blocks air flow and also insulates that are of the coil. That makes it easier for more frost to form - it spreads! After awhile the freeze sensor finds out and shuts your compressor down, allowing time to thaw.
Your a/c could have been OK all along, or the freeze sensor could be bad or installed wrong. But even if it all good, hot humid FL summer requires HIGH FAN.

Sorry, but if the freeze sensor is installed in the CORRECT location, the Evap will NEVER ice or freeze on any part of the coil. Regardless of Humidity or Fan Speed. To The OP, Are you stating the FAN and Compressor shuts off or only the COMPRESSOR? Doug

PS, That manual takes into account mechanical controlled AC units that do not have a wall tstat. They WILL Ice/freeze in Lo fan hi humidity conditions.

Doug, Thanks for the clarification on Freeze Sensor. We've had only the mechanically controlled ones, like an old two-knob window shaker, both Coleman Mach.

Let me ask... Does the freeze sensor then put the compressor on a duty cycle, where it takes time out to keep frost from forming? I'd thought the non-ducted a/c units like ours were a little more effective in cooling a coach on a hot day, than ducted ones. If for no other reason that the ducting was small and up in a hot roof area. We can run our Mach 15 full time on high fan all day. Doesn't freeze over, and sometimes it'll actually cycle, but it doesn't time out on frost.

j-d wrote:
Doug, Thanks for the clarification on Freeze Sensor. We've had only the mechanically controlled ones, like an old two-knob window shaker, both Coleman Mach.

Let me ask... Does the freeze sensor then put the compressor on a duty cycle, where it takes time out to keep frost from forming? I'd thought the non-ducted a/c units like ours were a little more effective in cooling a coach on a hot day, than ducted ones. If for no other reason that the ducting was small and up in a hot roof area. We can run our Mach 15 full time on high fan all day. Doesn't freeze over, and sometimes it'll actually cycle, but it doesn't time out on frost.

The reason ducted work better is because you can get cold air more evenly thru out the RV. The freeze sensor when it gets to the freeze part tells the control board to shut down the compressor. Once the Evap warms up enough to close the sensor the compressor comes back on. I believe RVP has a kit to install a freeze sensor on mechanical AC controlled units. Doug