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rickybobby
09-03-2007, 02:46 PM
looking to buy used TM & wondering about the advantages & disadvantages of the placement on the AC. Do the ones ones mounted on top do better than the ones placed inside on the door side or worse?? Any technical info or personal experience is greatly appreciated.

Paul_Heuvelhorst
09-03-2007, 09:32 PM
Our 1998 2619 had the side air. It put out lower BTU's of cool air than did the A/C mounted on the roof of the larger TM's at that time. Ours was 10K BTU if I remember correctly.

In my opinion, the roof air distributes air more evenly throughout the trailer. I made a cardboard shroud to direct our side air to the front of the trailer.

rjohn60
09-05-2007, 01:24 PM
Our 1998 3124K has the roof mount AC. I set it up in near 100 degree temperatures, put the AC on, and set the control on median level. When we came back a few hours later the inside was nice and cool.

wbmiller3
09-05-2007, 07:25 PM
We have the side mount, and it's OK, but I would rather have the top mount. The additional storage would be nice and I think the top mounts are more powerful. But, no plans to replace the current trailer.

We had a problem with water pooling in the bottom of our side mount A/C. This was not a problem with the drain hose but rather a design "feature" of the A/C unit. It was made to keep about a half inch of water in the bottom. I do not know why but speculate that in less humid climates retaining this water may prevent the constant dripping you see from some window a/c units. The trailer drain hose would not start to drip until this 1/2 inch deep receptacle overflowed.

Since we camp often in the humid southeastern summer, at the end of each trip, we would have a 1/2 inch of water in the A/C, unknown to us. On the drive home or to another campsite this water would slosh out into the inside of the trailer where we would find it soaking the carpet and discoloring the cabinet. It took us a long time to figure out where this water was coming from.

Once the clue-bird landed on me, I pulled the unit out of the trailer and carefully drilled many drain holes in its built-in "pan", then re-installed it. Ever since then the drain hose drips constantly and no more water in the trailer. That was about four years ago.

mjlaupp
09-06-2007, 08:27 AM
RickyBobby
Having owned a 2 TMs, a 1998 2720 with a side mount A/C and a 2003 2720SL with a top mount A/C, I can tell you that the top mount 13,500 BTU unit will cool the TM much faster and colder than a 8,000 - 10,000 BTU side mount unit. With the side mount I was never able to keep the inside cool enough in mid summer high humidity days here in the south. The top mount unit can freeze you out on any given day. I keep the temp knob set at 40-45%.

WBMiller3,
The water in the pan is retained for the slinger ring on the condenser fan. It throws the water onto the condenser coils so as to increase the A/C cooling efficiency by water evaporation.

Mike

PopBeavers
09-06-2007, 11:45 AM
On the one trip where I had a reason to use my roof mounted a/c it did not freeze me out. Outside temperature was 110 in the shade and I was parked in full sun.

This was an unusual day, even for Lake Almanor, CA, July 2005.

wbmiller3
09-06-2007, 03:28 PM
Mike,
Thanks for the info! From looking at the unit it was clear that the water retention was designed in. Nice to know what it was for.

I guess I dropped my unit's power a bit, but that's OK...couldn't take the water coming in. Definite mildew potential in our climate if we didn't open the trailer up and dry it out on arriving home.

Bill

race38
09-09-2007, 08:31 AM
I installed a new side unit in my 91 model this year and it does not do a good job of cooling.You have to keep fans going to circulate the air and that takes up space.Seems that the best it can do is 20 dregrees below outside temp. When you are at Myrtlebeach and it hits 103 , the camper can be a little uncomfortable.I always try to find a shady area to set up in. I would go with the roof top mounted unit if I had to do over.

Joe
09-09-2007, 02:43 PM
On side mounted units you need to put a shroud around the unit so that all the hot air coming across the coils is 'piped' to the outside. If you don't do this, the hot air from the coils will be sucked around to the intake on the sides of the unit and just blow hotter air across the coils. It can get so hot that the head pressure on the unit will rise and shut the unit down. The units installed by TM had a piece of sheet metal from one side, over the top, and down the other side. It extended from the unit cabinet to the grille on the side of the trailer.

Paul_Heuvelhorst
09-22-2007, 06:35 PM
On the one trip where I had a reason to use my roof mounted a/c it did not freeze me out. Outside temperature was 110 in the shade and I was parked in full sun.

This was an unusual day, even for Lake Almanor, CA, July 2005.

Aren't you glad you weren't in San Jose on the day? It is still several degrees cooler at Lake Almanor than in the valley on any given day! ;-)

Leslie & Nick
09-22-2007, 07:00 PM
On side mounted units you need to put a shroud around the unit so that all the hot air coming across the coils is 'piped' to the outside. If you don't do this, the hot air from the coils will be sucked around to the intake on the sides of the unit and just blow hotter air across the coils. It can get so hot that the head pressure on the unit will rise and shut the unit down. The units installed by TM had a piece of sheet metal from one side, over the top, and down the other side. It extended from the unit cabinet to the grille on the side of the trailer.

Aha! I wondered what that strip of metal was intended for!

Even with the 'shroud' in place, I think the side mounted AC is only barely adequate, especially when the outside temperature gets over 85-90, with like humidity. It's better than having no AC, but I can see why TrailManor started using roof mounted units in 2002 -2003. You gain a cabinet, and get better air circulation too! Next TM will have roof mounted AC ;)

mike-rm-cd
10-07-2007, 08:31 PM
Nick: Our '02 2720SD didn't have an A/C. It DID have a beautiful laminate floor, thanks to you. That TM has been sold (by the Auburn Dealer) to a couple in Yakima, who had an A/C installed. On the passenger side, I assume.

Our new 3326K, (roof-mounted A/C) is pretty awesome. In 94 degree temps, it brought inside temp down to 72-74 or so. It IS noisy, mostly with the volume of airflow, forward and back into both ends of the new TM.

We're off tomorrow (10/8) for a month-long trip to OR, CA, and return. We'll report back.

Mike - and thanks for all of your tips and suggestions.

Senorsedona
10-08-2007, 01:35 PM
There are advantages to both. In general.....the side mount is quieter and can be run on 20amp. The roof air is more efficent, but is noisier & should be run on 30amp only.
If you can bring the air inside down 20 degrees cooler then the out side, your unit is doing a great job. You really shouldn't expect more.

Have fun.............

Jack

Leslie & Nick
10-08-2007, 02:03 PM
...... It IS noisy, mostly with the volume of airflow, forward and back into both ends of the new TM.

Just my opinion, but I'd put up with the noise, versus the "so so" cooling that my side-mounted unit provides. Guess it depends where you live though, the side mounted units might be OK in a more temperate climate, here in the deep south they don't do the job :)

Nick

larsdennert
10-09-2007, 01:05 AM
I was in UT over the summer and it was 108. The roof AC brought down the temp into the 70's. Gave the kids a cold. :(

mike-rm-cd
12-03-2007, 07:51 PM
We have used our roof-mounted A/C only a few times. When we have, it has performed very well, and noisily.

The folks who bought our traded-in, 2720 SD, had the dealer install a side-mounted A/C.

That dealer (Auburn RV, Karen) called (after our order was in) to suggest that maybe we might want to rethink our (my!) decision to NOT have the factory install the roof A/C. Karen said that the last TM they had (new) sat in the dealership for a year, and that it always looked, "forlorn."

In 94 degree weather in Sept, the A/C paid for itself.

Mike V.S.
12-04-2007, 07:56 AM
One thing nobody has mentioned as a side unit advantage is how easy and cheap it is to replace or upgrade. I pulled my factory unit out and put a bigger one in for about $150. There is alot of extra room inside the cabinet area to go bigger. The air flow from the top does sound like an advantage though.

wbmiller3
12-04-2007, 05:28 PM
I'm glad to hear that. I was wondering how much trouble & expense I would have finding a replacement when that day arrives. What did you get, if you don't mind my asking?

Mike V.S.
12-04-2007, 06:00 PM
Yes Bill, I put an 8500 BTU General Electric in that I bought from Brandsmart. It has the auto thermostat that shuts on/off automaticly as well as a remote control (needless!) My old unit was 7000 BTU I think and it has made it much cooler. The only extra work was replacing the metal shroud that was talked about earlier, conecting the drain ( a little bit of a headache) and redoing the cosmetic wood trim around the front panel. It was actually pretty easy. There was still some room left inside if I wanted to go bigger.

B_and_D
12-04-2007, 07:48 PM
Mike, was your cabinet around the side A/C irregularly shaped? Mine was angled right towards the back where the vent it, and it took up a lot of room from the cabinet on the right. The outlet was mounted to the cabinet wall. I pulled out the A/C when it died, moved the outlet, and took out the cabinet wall. We just don't need a/c here, but it could easily be replaced.

Mike V.S.
12-04-2007, 07:54 PM
B+D...I dont think so, its been about six months since I did it and dont really remember anything like you described.

wbmiller3
12-05-2007, 04:55 PM
Thanks for the info!

Pat Stafford
12-21-2007, 05:37 PM
Our 3124KS has the AC on the roof and it cool great in over 100 degree weather. We also epoxied an aluminum strip on the ceiling to direct the air more evenly. It works great.