# Carrier V A/c Fun Facts - Sort Of



## Ghosty (Jan 17, 2005)

Its over a 100 here in South Texas today -- AGAIN.









If your temp does not get past 90 then youre probably wasting your time reading the following whining...

Just spent the last four days camping on the beach at Mustang Island Corpus Christi. Absolutely great â€" temp was over 100 every day and the ocean was only about 50 feet from the trailer during high tide...

Met a fellow Keystoner (2005 Keystone Tail-Gator model) who works for Transport Carrier A/C.â€¦ I was complaining a little that his A/C seemed allot colder then mine...Thirty minutes and several beers later I was an A/C master.â€¦

Some interesting info I gained. The Tail-Gator and Outback have the exact same Carrier Air V A/C. Big difference is: Ours is vented, theirs is not.,

Tail-Gator blows directly from the condenser. Like a window unit at home. No loss of temp and no loss of forced air pressure. At 100 degrees outside his trailer was 68, mine was 84. (Outback air leaves the condenser and gets pushed across almost 24 feet of narrowly formed insulation against a hot ceiling to exit during which it looses some air cooling temperature and air pressure).

Outback A/C is rated to keep the inside air approx 18 degrees cooler then outside air.
Tail-Gator is rated at 35.

So when its 100 outside the best you technically can do inside is 82 in the Outback. (65 in the Tail-Gator)

Difference is caused from insulation, radiated space area, forced air pressure, ambient temp, etc, etc â€" but mainly our air is slowed down and heated as it is pushed across a hot ceiling and thus looses its cooling volume)

So if you donâ€™t think that youâ€™re A/C is acting correctly take the outside temp â€" then subtract (app 18) and thatâ€™s what the coldest your TT temp technically could be. Another quick check is to take the temp of the air coming out of any of the four vents â€" this should be registering right at 50 degrees.

also -- air flow should be about equal out of each of the vents. The A/C is dual ducted meaning that there are two vents each off of two intakes at the A/C -- if you have one side blowing harder then the other then you want to get a mirror and flashlight, remove the circular vents, and see if you have any collapsed ceiling.

If you ever loose your remote the emergency A/C button sets the A/C at 78 degrees constant.

Never let your A/C loose power with it running three times in a row... if this happens you have to reset it at the circuit board...

PS â€" Before anyone jumps on me I know there are allot of other factors as to outside vs inside temp â€"â€" humidity â€" number of folks in the trailer â€" if you open and close the door 100 times, etc etc. All Iâ€™m pointing out is that the Carrier A/C is a good solid A/C, ours is just ducted wrong â€" I am thinking about trying to figure out a better way of getting the air out and still use the vents â€" maybe some sort of solid insulated ductwork or somethingâ€¦


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## Reverie (Aug 9, 2004)

Just my two centavos worth...

The Carrier A/C unit is a good idea but it should have been vented through the floor vents. Don't get me wrong, I think the floor vents arent' that great shakes BUT since they are already there, it would have made more sense. I camp in 90 degree weather with close to 100 percent humidity. The Carrier unit is well built and the remote is simply a great idea. I just hope they tweak the design a little.

Reverie


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## cookie9933 (Feb 26, 2005)

Why do I keep looking at OB posts?















It's because this site has so many capable fellows that glean info and share with the rest of us Outbackers. Ghosty has become our AC "consultant" through much suffering and agravation. He is our AC wise one
































































Thanks for educating us. I hope you get some relief from the heat down in Texas









Jan


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## Ghosty (Jan 17, 2005)

Actually the Carrier guy said that Carrier worked pretty hard Public Relations-wise with Outback NOT to vent this A/C. They were afraid people would do what i did (jump to the conculsion that this A/C sucked) and this would hurt them with their Home and Industrial sales... but Outback won out by threatening to use Coleman and the rest is history...

As for venting under the trailer --- two things...

one -- the hot water pipes are already running along the venting system to help keep the trailer warm in the winter... so you would be cooling off the hot water or hot water warming the cold air... and

second .. hot air rises.. cool air sinks... so you would have to find a much better blower system to us to force the air from the condensor.. around the trailer to the bottom .. and then back up...

If you ever just get bored to death drop the manifold plate (do-hickey that forces the air from the fan into the vents) and fire up the A/C -- holy cow -- its like standing under a cold tornando -- so I know the A/C pumps out -- but you can't run the vents without the manifold present...

I for one -- if my A/C ever goes out again... will be thinking of simply putting in a drop down non vented uint...

I have taken the A/C completely apart -- I mean to the point where there is a giant hole in the roof .. and have taped and fixed my duct system that seemed to have collapsed halfway from the A/C -- but still think that I can design a better system of getting air out -- I just have to figure out how...


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## NDJollyMon (Aug 22, 2003)

Excellent info Ghosty!


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## cookie9933 (Feb 26, 2005)

Ghosty,

The other day I took off the bottom plastic panel, intending to see whether the unused holes were taped off. (Was it your gallery pic that shows this?) Anyway, when I got the plastic piece down I saw the four large bolts that hold the metal frame to the rooftop unit. Looked like the roof is sandwiched between those pieces. But then I thought that if loosened, I might be separating an adhesive bond and that the AC would leak whenever it rains. Am I wrong about that?

Actually, we get good airflow from all four ceiling ducts and cooling doesn't seem inadequate. So maybe I don't really have a reason to look for a problem. It's just that I have found some examples of less-than-wonderful assembly by the boys and girls in Goshen and I wanted to know that they got the AC right.

Bill


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## Ghosty (Jan 17, 2005)

The four bolts bascially sandwich the bottom metal manifold to the top cover...

taking them off should be completely safe and make sure though that when youput them back on that you tighten them down a bit (a bit being the technical word) to insure that water does not leak in...

if you have good airflow out of all four vents and they feel equal in pressure then there is probably no need to take down the A/C... if you notice a reduced flow from one side to another then you probably have air leaking out and heat leaking in and should pull it down to have a look-see....


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## hurricaneplumber (Apr 12, 2004)

Without a ducted system, air distribution would be poor with complaints of stagnant areas mainly towards the camper ends. the directional diffusers allow adjustablility and direction control where to put the air. A system that only dumps in the middle will overcool that area and not provide proper cooling to the ends. Once the stat is satisfied with this system, the ends will even get hotter. A ducted system is absolutely the best for proper air distribution and overall cooling performance in a camper shaped vehicle, long and narrow.

To use the furnace fan and blow through the floor vents will also cause poor air distribution, cold air is more dense and requires a larger fan than does heating. Stagnation at the ceiling level down will cause a uncomfortable situation. AC's main purpose is for occupant comfort.

There are many, many factors, but ultimately, a ducted system provides better occupant comfort and temperature distribution.

I would evaluate your system, I was in darn near 100 degrees and I could get mine down to 72 easily and there was absolutely no shade anywhere on the camper. Have your system serviced to check refrigerant volume and condenser operation. You may also have a air disruption somewhere, something just doesn't sound correct with your system operation.

Good luck

Kevin


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## Ghosty (Jan 17, 2005)

BUT -- the problem is that the Carrier fan is under powered to push the proper amount of air through the ducts.. venting is a great idea -- if it works correctly

also -- consider your A/C blessed since yours is getting 28 degrees colder inside then outside when technically the difference should be more like 18 according to the Carrier Service manual....


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## fixjet (Jan 19, 2004)

I remember last summer on a three day outing it was 95-98 everyday in direct sunlight. Typical high midwest humidity and we had no problem getting the temp down into the low 70's with great airflow. I love the system and the air distribution adjustability.


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## CamperAndy (Aug 26, 2004)

Ghosty said:


> BUT -- the problem is that the Carrier fan is under powered to push the proper amount of air through the ducts.. venting is a great idea -- if it works correctly
> 
> also -- consider your A/C blessed since yours is getting 28 degrees colder inside then outside when technically the difference should be more like 18 according to the Carrier Service manual....
> [snapback]44215[/snapback]​


I have tested mine a couple of times in the driveway, I most always camp without power so the AC is often just extra towed weight but I still want to make sure it works.

I get from 27 to 36 delta temperature from the air inlet to the air outlet. I have not had any icing yet but we dont have much humidity here. I have only tested it when the outside air temp was 85 so maybe I have not stressed it yet. I can't wait for the 3 days in August when it hits the upper 90's!!!! The really big delta was when I had the fan on low to keep the noise down and it still had enough air flow to chill the trailer to 70.

Just so you know AC in houses are an option around here until you get up to the $300,000 plus range, then they just assume you want it.


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## hurricaneplumber (Apr 12, 2004)

As a side note, temperature delta T or difference is based on return air temperature minus supply air temperature. The return air temperature will not be the same as ambient outdoor air temp, it will be less (except at initial start-up when the camper inside is hot and the same as outdoor temp). Assume a return air temperature of 80 degrees and use this 18 degree difference, the supply air temp should be around 62 degrees, which sounds reasonable. And all depending on RH, amount of outside air introduced by door opens, occupant loading, etc. Temperature delta T varies by many components, so just using that to judge performance is not very accurate.

Try measuring the actual supply and return temps for confirmed data.

The condenser is the component that will see the outdoor air temp, not the evaporator which provides the cooling medium for the air distributed to the space.

Just some more thoughts.

Kevin


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## GlenninTexas (Aug 11, 2004)

Not to highjack the thread, but on a similar note I was camping in 100 plus degree weather a few years back out on the good ol' Frio river. The way my TT was positioned exposed the refrigerator to the majority of the days sun. The frig could not keep anything cold during the day until I rigged up a tarp to shade the wall outside of the frig. So just a tip, if your camping in very hot weather try to position your rig to maximize shade on the frig. I would suspect that the AC would also benefit from some shade as well if its possible.

Regards, Glenn


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## tdvffjohn (Mar 10, 2005)

Good point Glenn. Maybe thats why most refridgeraters are facing under the awning?

John


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## CamperAndy (Aug 26, 2004)

hurricaneplumber said:


> As a side note, temperature delta T or difference is based on return air temperature minus supply air temperature. The return air temperature will not be the same as ambient outdoor air temp, it will be less (except at initial start-up when the camper inside is hot and the same as outdoor temp). Assume a return air temperature of 80 degrees and use this 18 degree difference, the supply air temp should be around 62 degrees, which sounds reasonable. And all depending on RH, amount of outside air introduced by door opens, occupant loading, etc. Temperature delta T varies by many components, so just using that to judge performance is not very accurate.
> 
> Try measuring the actual supply and return temps for confirmed data.
> 
> ...


My delta T was measured in the trailer from the filter inlet to the duct work. I actually had temps as low 44 degrees in the duct work when the trailer temp was 80. I only expected 20 to 25 delta and was shocked to see 36.

It should be in the mid 80 again today and I want to run my new generator again so I will do some numbers again today.


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## hatcityhosehauler (Feb 13, 2004)

It's beginning to sound like a mechanical engineer's convention here.....









Tim


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## hurricaneplumber (Apr 12, 2004)

But Tim,
this is more exciting that just turning your fire extinguisher upside down and shaking it.

Mechanical folks are awesome......























How is your bag blowing going?

Kevin


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## cookie9933 (Feb 26, 2005)

Tim,

Right you are. "Delta" is a Greek letter shaped like a triangle and is used in many technical/engineering formulae. Translates roughly as "change in". Could be used with any variable (time, velocity, position, etc.)

Bill


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## camping479 (Aug 27, 2003)

Flew on delta a time or two

Mike


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## hatcityhosehauler (Feb 13, 2004)

> Could be used with any variable (time, velocity, position, etc.)


Bill, we use it in EMS too, to note any patient condition changes on the paitent care report that gets filed with the E.D. chart.

Kevin,

I've actually had the bagpipe now for about 7 weeks, and it is coming along, although you won't be seeing me in a kilt anytime soon.







I do move almost as much air through that bag, then the Carrier A/C moves through Ghostys trailer.









Tim


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## NDJollyMon (Aug 22, 2003)

"I do move almost as much air through that bag, then the Carrier A/C moves through Ghostys trailer. " Tim

Somehow....I believe that.


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## Banjo (Aug 1, 2005)

Ghosty said:


> Its over a 100 here in South Texas today -- AGAIN.
> 
> 
> 
> ...


I have a 2005 30rks with the Carrier 15000. July 4th we burned up at Texoma-couldn't get it below 85 to 90 inside with the kids coming in and out. It spent the next 3 weeks in the shop where they reported that they "sealed some ducts" and it would give them a 22 degree drop which is, "better than expected". I took it home and parked it in the driveway and found that there may be a little more volume out the vents, but in 90 to 100 degree weather it will only drop it 14-15 degrees. Yesterday was 94 outside/ 80 inside. That won't hack it in Dallas. I havent measured the temp at the vents, but I will tomorrow.
This unit only recools the air from within the camper doesn't it? It doesn't pull in hot outside air to cool does it? If you are recooling the air inside, you would think you could really drop teh temps down.
Will


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## toolman (Jul 12, 2005)

Its currently 104 outside. My AC has managed to keep up pretty good. 78 inside the trailer and the AC is keeping up fine.

Toolman


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## aplvlykat (Jan 25, 2004)

I have no issue with our A/C. Today it was 102 outside and very little wind. The A/C dropped the temp to 76 and was cycling on and off all afternoon. I checked the ducts like someone suggested and have very strong flow out of all the vents. The only problems I found was in the return air where they used very little tape. I installed 1/2 inch foam and resealed the return air box. This may have helped a little with my unit and I know it couldn't hurt. Kirk


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## slickaroo (Sep 11, 2005)

Thanks Ghosty for the tip on taking down the air conditioner and checking for air leaks. We took our first trip in or '05 sydney 30rls last weekend and was dissappointed by the air not cooling enough. This is a 15,500 btu and didnt do as well as our last trailer with a 13,500 btu. I read your post and lowered the unit, and sure enough there were two holes where about 25% of the air was blowing into my cieling voids. I put plen







ty of duct tape over the holes and now It blows much harder and cools at least five to ten degrees cooler. I hope it was ok to use the regular gray duct tape, I didnt have the foil looking tape. I have am also planning several other things found on this forum to tweak up my trailer.


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## huntr70 (Jul 8, 2005)

slickaroo said:


> there were two holes where about 25% of the air was blowing into my cieling voids. [snapback]54019[/snapback]​


Maybe that's why there was air blowing out the light holes in my kid's bunk when I moved the reading lights......I had the fan running to move the air in the OB while I was working.









Just kidding...there was air coming out the ceiling, by already knew why, just didn't get to dropping the Ac unit yet.

Steve


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## Thor (Apr 7, 2004)

The best solution is to camp north of your border. I have owned my Outback for 2 years and only haved used the AC a few times and I thought it was too cold. We mainly use the dry mode. I need to trade my AC for a furnance - Now we are talking camping









All kidding aside - Can the air flow be increased by changing out the fan? Or will that effect the AC unit. I know with my home, I changed out my fan to a 2 speed. The fan runs on low until the heating or AC kicks in, then it switches to high speed. I found that with the new fan the temp. is more even throughout the house and the heating or AC actually seems to work less often.

Thor


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## CJ999 (Aug 11, 2005)

Ghosty said:


> If you ever just get bored to death drop the manifold plate (do-hickey that forces the air from the fan into the vents) and fire up the A/C -- holy cow -- its like standing under a cold tornando -- so I know the A/C pumps out -- but you can't run the vents without the manifold present...
> 
> [snapback]43992[/snapback]​


The other thread about A/C that is running right now caused me to go back through the forum and read some older threads....

I'm thinking I may try this end run around the vents this summer, with a fan inside the trailer to circulate the air... just to see how it compares in cooling the trailer down.


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## tdvffjohn (Mar 10, 2005)

I just finished taking down my AC plate held up by those 4 bolts. I figured why not, lets take a look. I was surprised to see that there are 2 ducts that all the cold air is supposed to go in and 1 hole (2 1/2 in x 4 in )on the sheet metal that only the wires run thru and it is directly into the ceiling area. I taped up the opening where there the wires go thru with duct tape.

I was always satisfied with the AC as it kept it cool in Myrtle Beach last year, but sealing off that hole made a difference in air flow at all the vents.

It was easy to do, remove the cover with its 4 screws and then loosen one bolt out an inch and then remove the other 3 completly. This way there is plenty of room to gain access and no strain on it hanging on the wires. It took me 20 min all totaled.

Cleaned my awning also with the water, bleach, simple green mixture, closed it up 1/2 hr.......white again









John


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## Sluggo54 (Jun 15, 2005)

"I'm thinking I may try this end run around the vents this summer, with a fan inside the trailer to circulate the air... just to see how it compares in cooling the trailer down."

Cookie, I have no A/C issues - but then, it is a Coleman 15000







For curiosity, I took a couple of the ceiling vents off and and looked at the ducting. It is round, insulated duct front to back. No crush that I could see, and very even velocity at all vents.

I did buy a small oscillating fan which sits on the floor, doing its thing very quietly. We do notice that temps are more even with the air being blown around a bit. I've never had it above "LOW". Seems to be enough just to move it around a bit. Maybe it's just perception...

Rat now, we are in Yankton, SD at Lewis & Clark SRA. Pretty place, but mighty warm, and it's fixin' to get warmer tomorrow. In order to avoid the increased heat here, we are heading for Samuel R McKelvie National Forest SW of Valentine, NE tomorrow. It will likely be 10* warmer there than here, but by golly, "here" won't overheat us tomorrow!

Sioux Falls is a very attractive city, butlike the man said - I'm not much of a city type guy. Visited Madison today, our new legal residence. About 6,500, nice clean town, friendly people. I think I would like it there. Oh, yeah - it takes one day and ten bucks to get a carry permit.

Slug


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## Dark Green Dmax (Aug 2, 2005)

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