Sweaty windows....or not? - Montana Owners Club

Ozz · 01-17-2007, 02:45 AM

Here on the Island at South Padre, the humidity is about as high as it gets, the cold front hit us, of course not to the degree that many of the states have experienced. It's 42 outside.
I have noticed the inside of most all of the windows of surrounding RV's, 5ers, TT's, are completely covered with droplets as I gaze out the window, the class A's are not. I saw a Jayco pull out a few minutes ago, every window was covered with water inside.
As I returned from the kitchen with a fresh steaming cup of Hazelnut, I glanced over at the door window, it was dripping with moisture. All of my other, double insulated windows are as clear as ever, now the bottom track on some are wet, goes to the Iced Tea glass example, of a cold surface collecting any moisture in the air. Dew point stuff......
At this temperature overnights, we have a nice 1500 watt thermostatically controlled heater in the bedroom, set at 65 degrees, which cycles on and off nicely. In the living room downstairs, my built in Grainger's 1500 watt heater, set on medium. I run the main overhead ducted A/C fan only, on medium to circulate the entire trailer air. No Propane heat at night, I kick it on for 5 or 6 minutes every morning, then off for 24 or so hours.
If any one's borderline, with the decision of ordering a new Monte with double pane windows, do it.
Just some 'Cabin fever' musings...........

Ozzie · 01-17-2007, 03:02 AM

That 'always on' feature of the furnace fan is something I would be most interested in doing. I'm sure it helps with not only filtering the air, but with cold spots in the rig.
We have our fan running at home for the same reasons.

I would love to be able to run our furnace fan with the same convenience we can run our AC fan. With a Hi/Low switch too...(that fan is rather noisy)...

Cabin fever...now that's another malady running rampant around here.
It forces me into fixit mode since I can't use it. I've got to put those card cards away...

SlickWillie · 01-17-2007, 03:19 AM

We have the single pane windows, and I can assure you, they are sweating bad. I actually having some of those damp rid bags hanging around. I've had one in the closet for a couple weeks and it is half full of water. One question; are the double pane windows sealed well? I know in our stick house, one got broken, and when it was replaced it has always had trapped moisture between the glass. Also a friend has several double pane windows that fog up between the glass (stick house).

Ozz · 01-17-2007, 03:58 AM

Ozzie, I will wire a switch up for the furnace to run that fan continuous, that is an upcoming project.
Will, so far, all the seals are working fine.
You can try running the A/C unit, if it's not too cold outside, above 45 or so for a while, then the furnace, or electric heat, that will dry out the space. On computer room A/C units, we have a reheat coil to drop and control the humidity.

JimF · 01-17-2007, 04:07 AM

Ozz, we noticed the same thing you did on the window frosting a few weeks back. We also have the 07 3400RL with dual panes. We were running the ducted fan and have a 1500w electric heater as suppliment. We did not do the one in the bedroom as it got to warm for me. When the temp got down to the 30's we had to go to the furnace, but the unit stayed very plesant. Sure beat the heck out of the old Terry. We also noticed all the units around us with frosted windows and we personally would never do the single pane windows again.

richfaa · 01-17-2007, 04:07 AM

I do not know what we are doing wrong.We have the single pane windows and have not been troubled with sweating.Right now the outside temp is 39.1 and the inside temp is 71.3 and all the windows are clear.We have not yet seen sweating windows. We do keep the overhead vents cracked for ventilation. This Am I did a little experiment that any of you can do, Using my handy dandy Radio Shack IR Thermometer, the one we use to shoot tire temps. Outside temp 39.1..temp on the single pane window 56.8 temp with the day night shade down 73.1..no sweating. Try it on your single and double pane windows..data does not lie..Also no moisture in the closet???

SlickWillie · 01-17-2007, 04:11 AM

I actually have a dehumidifier unit in storage back at the home base. It is a little bulky for the RV though. Our propane heat runs very minimal, as I run a 1500 watt electric heater on the 20 amp microwave circuit. I looked at your heater mod with interest, but our Mountaineer cabinet is a little different. I think the best solution to the sweating is a return to the tropical weather we enjoyed before this arctic blast.

Parrothead · 01-17-2007, 04:47 AM

We have the same experience as Rich. Single panes, vents open and no sweating. The outside humidity makes a difference. I don't remember if Rich is still at Lake Havasu but that area doesn't have much humidity. Our previous rig had a lot of problems with moisture but we haven't used our Drizit at all in the Monty.
Happy trails.....................

Ozz · 01-17-2007, 04:59 AM

Yes, the Desert with no humidity makes the difference. It's probably 90% here. Maybe 20 or 30 there.
We had a 30' TT with single pane windows here last year, same conditions, we couldn't even sit next to the window in the slide without towels over the blinds, as it was too cold there. All the windows were sweating. We ran two dehumifiers, small ones, designed for just this reason. It helped a little.

rlrich · 01-17-2007, 05:01 AM

Outside - 39.9 with relative humidity of 83% and cloudy, inside 68.7, inside dual pane 59.9 with IR thermometer.

jrgwdenner · 01-17-2007, 05:37 AM

Our single panes don't sweat either but we would definitely consider the dual panes on our next rig. Better insulation and noise control.

crandallbradley · 01-17-2007, 10:43 AM

Sitting in my 319BHD out here on the west cost S.F. bay area,with temps in the night down into the high 20s and only single pane windows,I have only one window that gets sweaty. (The one I sit by so it must be that I'm full of hot air.)I use one oil filled heater on high at night with the bathroom vent cracked and the unit's heater set for 55,my humidity has been mid 30s-40s. I have no complaints about moisture buildup,I thought it would be worse.

Montana Sky · 01-17-2007, 10:51 AM

I also have not had a problem with windows sweating. I keep the vents cracked all the time, and while showering or cooking I run the FF.

On side note. Are the dual pane windows still getting a lighter tint than on the single pane? I noticed that at the rally last fall, all the folks who had dual pane windows had a very light tint. I really like the dark tint on my single panes better...

rak · 01-17-2007, 01:22 PM

We have dual pane windowes and cracked the vents. No moisture on windows or frames. Before we cracked the vents we did have moisture on the windowes and frames. Cracking the vents seems to be the answer. The tempature outside is 36 degrees, humidity 100% and 68 degrees inside. Can set next to the dual pane windowes and not feel a draft. Ozz, when you figure out how to wire the frunace fan to run all the time, please post the solution.
Have a great day. It is finally starting to warm up here at Sam Ryburn Res.

Dick

sreigle · 01-17-2007, 01:53 PM

We had a little sweating awhile back. Vicki then cracked a vent about a quarter inch above its base and end of problem. For immediate relief, running the fantastic fan seems to help but for continuous assistance the cracked vent seems to work. Single panes here but next time will be duals.

SKOOBDO · 01-17-2007, 02:17 PM

I do the same as most of the others, keep a vent crack, run my ceiling fan for circulation and no problems since I moved into this unit.

Wrenchtraveller · 01-18-2007, 02:44 AM

The nicest benefit of dual pane windows is they are not cool to sit next too. I have had to camp in freezing weather for many years because when my kids were young, we did a lot of skiing and used to stay up on the slopes in a slide in Camper. In 33 years I had 4 different slide in campers, the first 3 were single pane windows. My last one was dual pane.
The difference is like night and day. I am sure happy to have the dual panes in my Montana.
Warmer, quieter, no condensation, and in Canada, much higher resale price on a used RV.

sreigle · 01-18-2007, 08:40 AM

Quote:

quote:Originally posted by Wrenchtraveller

The nicest benefit of dual pane windows is they are not cool to sit next too. I have had to camp in freezing weather for many years because when my kids were young, we did a lot of skiing and used to stay up on the slopes in a slide in Camper. In 33 years I had 4 different slide in campers, the first 3 were single pane windows. My last one was dual pane.
The difference is like night and day. I am sure happy to have the dual panes in my Montana.
Warmer, quieter, no condensation, and in Canada, much higher resale price on a used RV.

Exactly the reason we'll go with dual panes next time and I'm kicking myself for not getting them this time. Because we have single panes, we put film over the windows when in winter weather. That gives the same effect but it is a pain to put the film on and take it off later. And, of course, we don't have the noise abatement nor heat reduction in the summer.

Ozz · 01-18-2007, 11:05 AM

It's hard to have all the goodies...I wish I had the Gel Coat, I just love the Montanas with it, GREEN with envy, but I don't have it, and have found no affordable way to get it, so I shall continue to see if I can find someone to rub 20 coats of wax on it...Ok, maybe not.

Montana_6708 · 01-19-2007, 05:57 AM

We are over in Brownsville and I have the problem with the "Dew" on the inside of the windows. I think I will try the fan switch addition. Need to figure out the furnace filter process. I do not know if we have one?
our unit is a 1999 Montana 3555 with 3 slides, and single pane windows. I would like to find replacement double pane windows, as I do have a small star burst ding in one of the small windows on the rear side.
How do I ID the right wire for the furnace fan?
Bob

Quote:

quote:Originally posted by Ozz

Here on the Island at South Padre, the humidity is about as high as it gets, the cold front hit us, of course not to the degree that many of the states have experienced. It's 42 outside.
I have noticed the inside of most all of the windows of surrounding RV's, 5ers, TT's, are completely covered with droplets as I gaze out the window, the class A's are not. I saw a Jayco pull out a few minutes ago, every window was covered with water inside.
As I returned from the kitchen with a fresh steaming cup of Hazelnut, I glanced over at the door window, it was dripping with moisture. All of my other, double insulated windows are as clear as ever, now the bottom track on some are wet, goes to the Iced Tea glass example, of a cold surface collecting any moisture in the air. Dew point stuff......
At this temperature overnights, we have a nice 1500 watt thermostatically controlled heater in the bedroom, set at 65 degrees, which cycles on and off nicely. In the living room downstairs, my built in Grainger's 1500 watt heater, set on medium. I run the main overhead ducted A/C fan only, on medium to circulate the entire trailer air. No Propane heat at night, I kick it on for 5 or 6 minutes every morning, then off for 24 or so hours.
If any one's borderline, with the decision of ordering a new Monte with double pane windows, do it.
Just some 'Cabin fever' musings...........

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