Adding Auxillary A/C System

[Wingate]

Has anyone added an auxillary A/C system to their TT.

I have a Jayco 298 RES with factory 15K ducted air and would like to add a 12K air unit to the bedroom.

Has anyone done this themselves? What unit did you use? Where did you purchase it? Time/Costs involved?



Thanks...

 

[EricBu12]

Does your trailer have it pre-wired? Mine did. just remove the vent and install the A/C per instructions. . I have a 15K unit as well ducted... I went with a regular 13. 5 A/C auxiliary... . if your trailer is not pre-wired, then you will have to run a wire to it. just price a unit and thats it. . Took a couple hours to put it up. . one thing is, the unit is pretty heavy. . . . The unit is connected to a wood platform. I hooked a rope to it to try to lift it from the roof... but it took someone else climbing the ladder from underneath, using his head to help lift it... . lol. . pretty funny but it worked. .

once I installed it and wired it, fired right up

 

[mwilson]

I think that the pre-wired/pre framed for 2nd unit trailers have a 50 amp entrance to carry the two units???



Your trailer probably has a 30 amp like mine.



Two units starting up takes some juice.



Mike.

 

[Bill Stockard]

I added a 13,500 BTU Dometic Penguin (low profile) to the bedroom of our '97 Hitchhiker we had at the time. The trailer already ahd a 15K BTU ducted A/C unit from the factory. It wasn't wired for a second A/C so I wired it in with a separate 20 amp hookup through a 20-amp circuit breaker. I took a 50 amp RV pigtail and split it between a 30 amp receptacle and a 20 amp receptacle. I used the 30 amp side for the trailer main electric cord and used the 20 amp for the additional A/C unit. It worked great in the hot 100 degree plus summer weather.



Bill

 

[HBarlow]

Wingate,

Check with Jayco or the selling dealer before you get too far into this project to find out if the bedroom roof was framed adequately for a second a/c unit.

A 30 amp trailer was often not framed for a second a/c. An a/c is too heavy to be bouncing around up there on a rough road unless the trailer roof was framed for it.

PPL in Houston is a good source for RV parts. There is another one in San Antonio - Tweetys.com - RV Parts & Accessories - 5th Wheel Hitches, RV Parts and Accessories .

 

[Bill Stockard]

Wingate,



Check with Jayco or the selling dealer before you get too far into this project to find out if the bedroom roof was framed adequately for a second a/c unit.



A 30 amp trailer was often not framed for a second a/c. An a/c is too heavy to be bouncing around up there on a rough road unless the trailer roof was framed for it.



PPL in Houston is a good source for RV parts. There is another one in San Antonio - Tweetys.com - RV Parts & Accessories - 5th Wheel Hitches, RV Parts and Accessories .

Before I added the second A/C unit to the bedroom of our Hitchhiker, I contacted NuWa, the manufacturer, about sufficient framing over the bedroom to support the second A/C. They assured me they frame all their trailers for supporting the weight of a second A/C unit in the bedroom whether or not they are factory pre-wired.



Bill

 

[MelvinPierce]

Before I added the second A/C unit to the bedroom of our Hitchhiker, I contacted NuWa, the manufacturer, about sufficient framing over the bedroom to support the second A/C. They assured me they frame all their trailers for supporting the weight of a second A/C unit in the bedroom whether or not they are factory pre-wired.



Bill

Most probably are, but I would check with the manufacturer. I would hate to get to my campsite, and find the AC laying on the bed, with the roof caved down on it! LOL

 

[TLane]

I checked with the mfg on mine, they said the roof would hold just fine - it has stamped steel trusses. I removed the vent (actually, hail removed the vent, I just removed the remaining frame). The longest time was removing the "goo" that sealed the vent, I didn't want to tear up the rubber roof. I added some wood and sheet metal around the vent opening to seal it off from the A/C; otherwise the A/C could suck hot air out of the "attic". I ran a new electrical inlet from the side of the trailer forward to the front storage compartment, up through the "shirt closet" beside the bed, and then through the roof over to where the A/C would be. I got my A/C from a local dealer, only about $10 more than online plus no shipping. In addition, I went back to them for 4 new bolts that go through the opening to hold down the A/C, apparently my roof is slightly thicker than standard (they exchanged them no charge).

When I want to use the front A/C, I run an extra 12 AWG extension cord that I carry from the 20AMP AC connection in the campground to the front inlet. I also added an additional outlet in the bedroom to run an extra heater in the winter. The camper plugs into the 30A outlet in the campground. This gives me plenty of power to run both A/C units in the summer.

I used ropes up over pulleys in my barn rafters to hoist the unit up (two boat winches mounted to the wall). I then backed the camper underneath the unit and lowered it down. Be careful with hoisting it up, don't let anyone walk underneath it, etc. I didn't record the actual time, probably spent a few hours over a couple of different weekends. I had removed the trim inside the vent and ran the electrical prior to getting the unit, so it was ready to go.

Before I bought mine I went to the mfg's web site and downloaded the installation instructions and read them. Yea, I know, I actually read the instructions!

 

[Bill Stockard]

Most probably are, but I would check with the manufacturer. I would hate to get to my campsite, and find the AC laying on the bed, with the roof caved down on it! LOL

It probably wouldn't fall in without sufficient bracing, but the roof would sag from the weight and hold rain water in a big pool on the roof around the opening which would eventually leak on to the bed.



Bill

 

[MelvinPierce]

It probably wouldn't fall in without sufficient bracing, but the roof would sag from the weight and hold rain water in a big pool on the roof around the opening which would eventually leak on to the bed.



Bill

That is what the "LOL" is for!

 

[Wingate]

wow... lots of good idas and suggestions already... this site is great!. .

I will check with my local dealer and verify whether its capable of holding another unit before buying. .

I wonder if one could add another breaker to the existing breaker box, check/replace the cord to ensure its capable of 50A service, and wire it all in to the factory system??

Although the auxillary cord idea is also great.

Another ??? how would I determine whether the unit is pre-wired for the second A/C unit without contacting the dealer?

FWIW, the service manager that gave us our walkthru made mention that we could add an auxillary a/c unit if we wanted to... not sure if that was just a general statement since it was about 105 degrees when we bought it, or if he was talking about that specific unit. . ??

 

[Wingate]

Wingate,



Check with Jayco or the selling dealer before you get too far into this project to find out if the bedroom roof was framed adequately for a second a/c unit.



A 30 amp trailer was often not framed for a second a/c. An a/c is too heavy to be bouncing around up there on a rough road unless the trailer roof was framed for it.



PPL in Houston is a good source for RV parts. There is another one in San Antonio - Tweetys.com - RV Parts & Accessories - 5th Wheel Hitches, RV Parts and Accessories .

I forgot about Tweetys... . I bought my B&W GN hitch from them. . Like keeping the $$$ in Texas. .

 

[TLane]

Take a look at the plug on the end of your shore power cord:
If it looks like a standard household plug, it's good for 15A.
If it's bigger and has 3 prongs, it probably is 30A, 120V.
If it's bigger and 4 prongs, it probably is 50A, 240V.
There should be a sticker on the RV as well.
You should also take a look at the wire, it should be printed or embossed with "10AWG" (30Amp) or "6AWG" (50Amp).

If it's pre-wired for a 2nd AC unit, you should be able to pull the trim out of the inside of the vent (something like 4 screws) and find the end of the wire. I'd look with the unit unplugged, just to be sure. Take a look in your breaker box, is there a second breaker labelled A/C 2 or something like that (I know, I'm dreaming). An A/C unit should have a dedicated breaker (so does the water heater, if it has the 120V heating element).

A 30A service won't run 2 A/C units, you either need 50A service or a second power line. I don't trust most of what dealers tell me. Call the mfg rather than the dealer.

 

[AClayton]

wow... lots of good idas and suggestions already... this site is great!. .

I will check with my local dealer and verify whether its capable of holding another unit before buying. .

I wonder if one could add another breaker to the existing breaker box, check/replace the cord to ensure its capable of 50A service, and wire it all in to the factory system??

Although the auxillary cord idea is also great.

Another ??? how would I determine whether the unit is pre-wired for the second A/C unit without contacting the dealer?

FWIW, the service manager that gave us our walkthru made mention that we could add an auxillary a/c unit if we wanted to... not sure if that was just a general statement since it was about 105 degrees when we bought it, or if he was talking about that specific unit. . ??

My recommendations:



With a TT with a 30A service I would NOT tie into existing panel. You CAN run two A/C's and still run your fridge on electric but won't leave any power left over. A Coleman A/C will run off of 11 amps with a 90* ambient and 75* indoor temperature. A fridge will draw about 4amps on avg. So you can do the math and safely assume that a warmer day and/or starting the unit off at 90 plus interior temp will add significantly to the amp draw of the A/C.



The part about contacting the dealer about structural integrity can be a mistake..... they will want to be the seller of the A/C so they are motivated by potentially getting the job of installing it. As previously discussed, contact the manufacturer! If the unit was pre-wired, there will be a single-gang electrical box in the ceiling with a blank cover plate concealing a 12awg romex suitable for running a unit. As a sidenote, most RV roofs are more than up to the task of supporting the weight of a typical RV A/C.



When you consider the 2nd unit, opt for the smaller capacity ... ... 7k, 9. 2k or even an 11k model to prevent short-cycling of the compressor. A unit that is over-sized for a traditionally sized RV bedroom will be annoying at best with the compressor short-cycling off and on repeatedly throughout the night. A smaller capacity unit will also offer increased humidity removal which may or may not be an issue down south in TX.



And don't forget to oder your ADP... . air distribution box... . with your new A/C. You will need the one for non-ducted use and has its own t-stat and fan control on the box itself. If you do not have power available there already, then you will simply fish the wire however you need to get it from the ceiling to the bottom of the trailer or outside storage compartment. Add the necessary electrical box to transform the interior romex cable to an exterior cord complete with the proper plug for standard 120v 20amp service. When you get to the campsite, you have your coiled cord prepped for service and ready t0 plug into the handy campsite power supply. Again, most campgrounds today have 30a or 50a plug while also sporting a standard 20a convenience plug.



Alan

 

[Bill Stockard]

I wonder if one could add another breaker to the existing breaker box, check/replace the cord to ensure its capable of 50A service, and wire it all in to the factory system??

No, without replacing the circuit breaker box and re-wiring parts of the trailer. 50-amp service is actually utilizing two 120-volt "legs" of a 240-volt circuit. Since no appliances in an RV are 240-volt the 50-amp 240-volt service into the trailer is kept split into two 120-volt legs. One A/C unit is on one 120-volt leg and the second is on the other 120-volt leg.



A separate 20-amp service cord wired through a separate 20-amp circuit breaker box for the second A/C is a much easier and simpler solution for a trailer that doesn't have 50-amp service and hasn't been pre-wired at the factory for a second A/C.



Most government sponsored/constructed parks and many modern RV parks that have been wired to code will have separate 30 amp and 20 amp circuits in the electric hookup box. Older parks and parks that have been put in on the cheap and not wired to code will have their 30 and 20 amp outlets wired together on a single 30 amp circuit breaker. In those parks running a second A/C unit won't work since starting/running the second A/C will probably trip the 30 amp circuit breaker.



Bill