TM a/c efficiency?

Gapopper · 08-11-2016, 12:11 PM

How well does a roof mount a/c cool a TM. My popup a/c has to work very hard to cool. It can barely keep up during the day.

rvcycleguy · 08-11-2016, 12:38 PM

Quote:

Originally Posted by Gapopper

How well does a roof mount a/c cool a TM. My popup a/c has to work very hard to cool. It can barely keep up during the day.

Most RV's will only cool 25 degrees below the outside ambient air temp. If it's 95 outside, you may only get close to 70 inside... And that's with no air leaks, door leaks, and possibly more insulation than a TM offers in roofs, walls.

**Bill** · 08-11-2016, 01:09 PM

The TM A/C is rated 13,500 BTU/hr. What was the rating of the A/C in your popup?

Although the TM does have some air leaks, the big expanses of walls and roof are insulated. This is quite different from the large expanse of canvas or uninsulated fiberglass in a pop-up, especially if the canvas is in the sun.

I would expect much better results in a TM compared to a popup. I'm not sure where the estimate of a 25 degree differential comes from. I guess it might be true if the TM is in bright sun - solar loading is a big factor. But I would expect it to do much better in a shaded location.

Bill

LoveToCamp · 08-11-2016, 01:35 PM

I'm with Bill. I don't see why a TrailManor AC would have problem keeping up. I have not seen a post on this forum where someone complained that their properly-working AC was not cooling their TM.

I have only had hookups twice, but the AC kept up fine. Had to turn it to "Low" after a while. It was about 90° when we used it.

Padgett · 08-11-2016, 06:03 PM

At Sun'n'Fun this year I used the AC on every break. At 95F in bright sun it took about an hour at LO COOL to get into the 60s and have the AC set to max cool cycle.

Dunno if mine is unusual but works very well (and all on a 2400W genny)

ps everything cleanable has been cleaned & running on a soft start device.

HIKERZ · 08-13-2016, 06:08 AM

I recently upgraded the original a/c with a Coleman Mach 3. 15k btu with the heat strip. It works well in the FL heat. Gives me about a 25 degree variance between outdoor and indoor. Just cools the unit a little faster. I have not tried the heat strip but I believe it will be about the same. Not really "heating" as opposed to just taking the chill off. An upside is that it is much lighter

oldstick · 08-13-2016, 07:16 AM

Quote:

Originally Posted by Gapopper

How well does a roof mount a/c cool a TM. My popup a/c has to work very hard to cool. It can barely keep up during the day.

From experience, It is many times more efficient than in a pop-up during the daytime hours. We mostly camp in GA and our previous unit was a pop-up and you could hardly tell the AC was on (except for the noise), especially if parked in the summer sun. For the pop-up, that trick of covering the canvas roof areas with the silver reflective sheets did help a little however, if we weren't lucky enough to find a shaded spot.

gonzo628 · 08-13-2016, 12:22 PM

Quote:

Originally Posted by oldstick

From experience, It is many times more efficient than in a pop-up during the daytime hours. We mostly camp in GA and our previous unit was a pop-up and you could hardly tell the AC was on (except for the noise), especially if parked in the summer sun. For the pop-up, that trick of covering the canvas roof areas with the silver reflective sheets did help a little however, if we weren't lucky enough to find a shaded spot.

We did this too (with our Damon CampLite 2408SLE).

My wife sewed velcro strips on 2 short edges and on the opposing long edges of 2 army survival blankets, then we velcro'ed them together. This assembly process was repeated for the other side, and a single blanket had velcro attached on the long side for the pull-out dinette. I stapled velcro on the inside of the roof just over each bunkend and my pull-out dinette.. During setup (after lifting the roof about a foot) i would attach the velcro'ed short end of the combined blanket to the roof over one bunk end, then repeat for the second bunk end. I would also attached the velcro'ed long end of the single blanket over the dinette pullout. After raising the roof completely, I would secure the blankets to the trailer with a combination of binder clips and bungie cords. It did make the bunkends and dinette more tolerable during the day. (wasn't ice cold but wasn't sweltering either). Plus, as they were army blankets, they had a drab green side as well. In colder months, you simply reverse the install (metallic side facing down) to hold the heat in. (To enable this, she sewed vecro on the opposite side, opposite end of each blanket).

Our Popup was by NO MEANS air tight, but to compensate, the a/c we installed was a 15k btu Carrier Air-V. It did great in that popup, plus it had a feature called air shower. There was a large round vent that you could open on the ceiling assembly, which would basically "shower" you in cold air (when standing directly under it). Perfect for the quick cool off.

Shane826 · 08-13-2016, 01:18 PM

Quote:

Originally Posted by gonzo628

...plus it had a feature called air shower. There was a large round vent that you could open on the ceiling assembly, which would basically "shower" you in cold air (when standing directly under it). Perfect for the quick cool off.

i need this!

gonzo628 · 08-13-2016, 04:41 PM

Quote:

Originally Posted by Shane826

i need this!

it was pretty awesome.

I think i need to engineer a way to drop the ceiling unit out of the recess when in use and return it to the recess for closing down the camper.... I am sure some type of flexible duct would be required to span the gap between the roof-mounted unit and the ceiling unit when dropped down....

Perhaps i am over thinking this. Maybe I just need a couple of guides for the vents? (It just seems inefficient to have the vents blow into the ledges of the roof before blowing through the camper).