rear ac - Montana Owners Club

bmill · 08-08-2006, 11:49 AM

Hi my name is brad my wife and i where very happy when we bought our montana 2006 3500rl but we have had alot of problems and we are looking for some help. The rear ac keeps freezing up and the dealer says that there is nothing wrong what should i do. also the day night shades seam very stiff we have losened them but they either fall and then we tighten them then they rip we have already had to replace two and we just dont know what to do just looking for some help

thank you
brad

CountryGuy · 08-08-2006, 12:00 PM

Welcome to the forum.

Are you running the fan on HIGH and Automatic?? There are several other hints that you will find on the forum, this has been discussed a number of times, as you read and use the search function you will find them.

Blinds, well, someone has a lot of hints on those, and I am sure they will share with ya! One trick is to run them up and down slowly, with two hands spaced equally from the ends, and to sorta roll the bar (top out, bottom in), and to pull slightly away from the window while you manage all that. IF they pull out of that little side piece, they will come apart and get snarly. Some have glued that piece on, others have used small screw to hold in place.

If you only have these 2 problems, you are looking GOOD! Some of us had a lot more, but Keystone has stood behind their units when it is a real big nasty problem. That A/C, by the way, may have more than a 1 year warranty, get out your paper work and read.

Glad you joined the ranks of the MOC.

Carol

Al & Carol Stevens Tipton, Mi.
Retired - Traveling with 4 Yorkies
Our Camping Rig History
Montana Improvements and Travel Reports
Our take on RV ownership, "Ya better be handy with your hands and handy with your cash."
2004 3295RK
2003 GMC 3500 Allison/8.1
PullRite 15.5K Super 5th
Line-X
JackRabbit tonneau cover
Bilstein shocks
Isolator Pin Box

Every day spent on earth is a blessing, every day spent in our Montana is a day blessed twice.

Montana Sky · 08-08-2006, 12:44 PM

Brad,
Welcome to the MOC!

I had the same problem you are having and have found the following tricks has helped solve the problem.

1. run your a/c in the "on" mode, not "auto"
2. run your fan on "high". Dometic a/c's are known for freezing up on "low fan speed"
3. I had my return airbox resealed. The shop found it was leaking cold air back onto the coils causing them to freeze.
4. Buy a voltage meter and make sure you have the proper voltage, this can cause your compressor to over work tripping the breaker.

Hope these tips help solve the problem. If not Dometic has a 3 year warranty on their a/c's, maybe a call to them is in order.

2004 Chevy Silverado LT 2500HD CrewCab Duramax
2004 Montana 3400RL

richfaa · 08-08-2006, 01:07 PM

As for the freezing A/C different things work for different folks.try all of the suggestions and see what works for you. We run ours on auto and make sure there is proper ventilation.We keep the roof vents cracked a bit and when it is real hot and humid we run the fantastic fan on manual low speed. remember hot air rises and you have got to allow for it to escape the camper. We have had no problems with freezing yet on either of our A/C's .

Rich& Helen N.Ridgeville,Ohio.

F-350SD, Lariat, V-10,4:30 Diff, tow command Long bed, Crew Cab Dually, 06 3400RL
Mor-Ryde Pin Box

Ozz · 08-08-2006, 01:37 PM

Hi Brad,
Are you positive that the evaporator coils are freezing up? The compressor will cycle on a freeze thermostat up in the coils, but sometimes it is hard to hear the compressor cycling with the fan running.
Running the fan on hi speed is sometimes necessary.
What is your unit doing? Is it just not cooling well enough? What temperature are you trying to maintain on the rear A/C? Your rear A/C unit is not ducted, is it? In the A/C industry, we see a 20 degree difference in the supply air from the A/C unit, and the return air to the A/C unit. I have noticed my main 15,000 BTU unit has a 25 to 28 degree difference at times.
If the air is 'Short cycling', it will drop the temperature of the coil and freeze, making the compressor cycle on and off, leaving the fan blowing, even though the space temperature is warm.
Montana Sky's #3 tip is a good one as well as his others.
Good luck.
Ozz

'07 3400RL 2nd RTU
2 Golf Cart batteries 1500 watt inverter
Honda 2000 Generator, 2nd one and twinning kit coming
Maytag's with 220 Dryer
Stationary domed Sat. dish
LCD 12 Volt Amp gauge
LCD Tank Monitor
3 added 120 volt outlets
On Board Air; 12 Volt Viair 450C compressor
2006 Ford PSD 4x4 Off Road Lariat
Hadley Air Horns
Truck inverter with 110 volts for laptop
Color Backup Camera
Awning lock

sreigle · 08-08-2006, 03:18 PM

DuoTherm AC units are notorious for freezing up when the fan is run on low speed in humid conditions. We always run ours on high. Auto has not been a problem for us. If you are already using high, then I'd suggest something else is wrong that requires servicing. If your dealer won't cooperate, call Keystone Customer Service and ask them for an alternate dealer to talk to.
(574) 535.2100 or (866) 425.4369 (Toll Free). Ask for customer service.

Good luck. Please let us know how this turns out. I have no idea on the shades. I thought just turning the spool just a little would fix that. Could it be you're loosening them a bit too much? Again, I'm just guessing on this one.

Welcome aboard MOC, Brad. Feel free to ask questions here. We'll do our best to help.

See another Montana or Mountaineer on the road? Flash lights twice, it might be one of us!
Steve Reigle (pronounced Regal)
Fulltiming since 3/21/03
'03 3295RK
'05 Ford F250 SD Lariat CC SB 6.0L PSD/TS FX4 4x4

Our RV Travels (now Firefox-compatible)

Montana Sky · 08-08-2006, 09:42 PM

Another thing I have found that helps keeping things from freezing up is to have your air "dump" into the living room. I find that when I close the gate and send all the cold air into the duct work, the a/c seems to slow down and eventually quits. Just another idea....

2004 Chevy Silverado LT 2500HD CrewCab Duramax
2004 Montana 3400RL

bmill · 08-09-2006, 02:17 AM

Thank you for all your helpful advice on the rear a/c i really dont know what is freezing but i do know that ice chunks fall into the fan and anybody in the living room gets sprayed it is a ducted a/c it just bothers me that the 13500 unit in the bedroom works better and a lot longer than the rear. i will try that small screw in the shades to help them from coming apart i really thank all of you for helping we have had alot of little things that went wrong with the montana but we just keep trying to fix them as they come hopefully my wife and i will get some pics on so you can see us and our camper also just one more thing on your montana are you able to watch a dvd in the bedroom and watch satelite in the living room

Thank You
Brad Miller

bmill · 08-10-2006, 03:18 AM

Hello just wanted everybody to know that the dealer was finally able to fix the air the anti freeze wire was on the wrong coil it was on the bottom coil when it was ment to be an the top and that fixed the problem so just wanted everybody to know just in case there was anyone else who had that issue
thanks again
Brad

richfaa · 08-10-2006, 04:03 AM

Good to hear of the fix..Glad to hear it was just one of those little things..and not a Keystone issue.

Rich& Helen N.Ridgeville,Ohio.

F-350SD, Lariat, V-10,4:30 Diff, tow command Long bed, Crew Cab Dually, 06 3400RL
Mor-Ryde Pin Box

sreigle · 08-10-2006, 06:14 PM

Any idea what this anti freeze thing looks like?

See another Montana or Mountaineer on the road? Flash lights twice, it might be one of us!
Steve Reigle (pronounced Regal)
Fulltiming since 3/21/03
'03 3295RK
'05 Ford F250 SD Lariat CC SB 6.0L PSD/TS FX4 4x4

Our RV Travels (now Firefox-compatible)

Ozz · 08-11-2006, 01:47 AM

Most freeze 'stats are a cap. tube running from the control to the surface of the evaporator coil, and sometimes clipped to the face of the coil, sometimes inserted into the coil. It's a hollow tube filled with an expandable gas that opens and closes an inexpensive switch. Silver in color.
Ozz

'07 3400RL 2nd RTU
2 Golf Cart batteries 1500 watt inverter
Honda 2000 Generator, 2nd one and twinning kit coming
Maytag's with 220 Dryer
Stationary domed Sat. dish
LCD 12 Volt Amp gauge
LCD Tank Monitor
3 added 120 volt outlets
On Board Air; 12 Volt Viair 450C compressor
2006 Ford PSD 4x4 Off Road Lariat
Hadley Air Horns
Truck inverter with 110 volts for laptop
Color Backup Camera
Awning lock

bmill · 08-11-2006, 03:07 AM

know i dont know but i do know that there are wires going to
the
coils and those are what needed to be moved
Brad

sreigle · 08-11-2006, 08:53 AM

Thank you both. I have saved this page for reference.

See another Montana or Mountaineer on the road? Flash lights twice, it might be one of us!
Steve Reigle (pronounced Regal)
Fulltiming since 3/21/03
'03 3295RK
'05 Ford F250 SD Lariat CC SB 6.0L PSD/TS FX4 4x4

Our RV Travels (now Firefox-compatible)

You may also like: