Try this first before you buy 2nd AC unit or bring your unit in for AC service.

[Tupelo Kid]

Originally Posted by halfprice

yes. I added the second ac like you described. I bought a 50 to two 30 adaptor for when I'm on shore power. With both acs on the temp drops fast. Then I only use the new rear ac. Keeps the mh cold and the noise level in the living room is much lower.

With no shore power and using the gen it's the living room ac only

Jerry

Jerry,
Did you install yourself or have it installed?
I'm asking to ensure there is indeed space in the roof and side walls to run the wire.
I have opened the fan unit in the bedroom and do not see a heavy wire for
a 2nd ac unit so I guess it would connect to the present 110 wire and run out.
Thanks for your update.

[halfprice]

Originally Posted by Tupelo Kid

Jerry,
Did you install yourself or have it installed?
I'm asking to ensure there is indeed space in the roof and side walls to run the wire.
I have opened the fan unit in the bedroom and do not see a heavy wire for
a 2nd ac unit so I guess it would connect to the present 110 wire and run out.
Thanks for your update.

Yes I did the install myself or I should say with a friend. In the vent opening there are 12 volt wires for a fan. I used these wires to fish the 10 gauge wires to the cabinet over the bed. Made a left turn and ran the wires through the cabinet towards the bathroom wall. Drilled a hole in the cabinet wall, whichi s also the bathroom/shower wall in my mh, so I could fish the wires down the wall then ran them under the bed to where all the other electrical components are located. Then out through the floor to where I mounted the new 30 amp plug The romex outside the coach I put in flexible conduit for protection.

It took about 8 hours to do which included several trips to home depot, a couple of do overs, due to no experience doing this mod before. But overall it wasnt very difficult. Just time consuming for lack of experience.


Jerry

[Tupelo Kid]

Originally Posted by Long & Winding road

Well the whole point of this tread was to improve our exsisting AC were we DONT have to run a 2nd AC.

Mine is much improved not to mention im saving like $800+ bucks over 2nd AC. I only have 30 amp service so that would only complecate things.

But If my RV was any larger I would have to go with 2nd AC.

Thanks. I know it is and understand.
Sorry for hijacking your post.
Your post is most helpful and I will be trying your mod once I dive into it.
However, I still want the 2nd ac unit regardless.
It will be used when needed in very hot situations and as backup should the orig fails.
I plan to run both at medium setting when we are out to protect the pups in case the
orig breaks the other unit will keep them safe until I return.
Along with setting up a warning unit for temp change to my cell. :-)
Thanks again.

[Pete'sMH]

Originally Posted by halfprice

Yes I did the install myself or I should say with a friend. In the vent opening there are 12 volt wires for a fan. I used these wires to fish the 10 gauge wires to the cabinet over the bed. Made a left turn and ran the wires through the cabinet towards the bathroom wall. Drilled a hole in the cabinet wall, whichi s also the bathroom/shower wall in my mh, so I could fish the wires down the wall then ran them under the bed to where all the other electrical components are located. Then out through the floor to where I mounted the new 30 amp plug The romex outside the coach I put in flexible conduit for protection.



It took about 8 hours to do which included several trips to home depot, a couple of do overs, due to no experience doing this mod before. But overall it wasnt very difficult. Just time consuming for lack of experience.





Jerry

Jerry, did you provide a new circuit breaker for the second AC? I’m considering an install and mostly wondering about pulling wires through the ceiling.

[halfprice]

Originally Posted by Pete'sMH

Jerry, did you provide a new circuit breaker for the second AC? I’m considering an install and mostly wondering about pulling wires through the ceiling.

Yes I added a breaker. Got it at Home Depot.

The wires through the ceiling was easy because of the 12 volt wires already there,

Jerry

[Tupelo Kid]

Originally Posted by halfprice

Yes I added a breaker. Got it at Home Depot.

The wires through the ceiling was easy because of the 12 volt wires already there,

Jerry

Decided to add a little update:
I had to take the MH into CW yesterday for them to replace slide seals or rubber flaps at the top and bottom of the slide.
While there I requested an estimate for installing the 2nd AC unit with a 110 plug. I also asked for an estimate to install the Gen Auto start.
They refused to install either.

Said they had never installed an auto gen start on a MH.
Also said they would not install the AC unit for 110 due to "some" AC's have a 2nd & 3rd start cycle to ensure the unit will start if it fails the 1st time.
Because of this they said most 110 GF plugs in the MH parks would trip and I would not be happy not being able to run the unit.

OH, and they didn't replace the slide seals after I've been waiting for them since Aug 2017 when we took delivery.

I took a detour from the service dept to the GM's office and inquired about this. He was in question about all of this as well.
On the Auto Gen start he said they had installed 2 of these in the past 2 weeks. He said they were both toy haulers but if they can install that they should be able to install in the MH.
He said he would call me in a day or 2.


I didn't know it was this difficult to spend my money.

Sure was easy to spend it for the MH but....

[Pete'sMH]

Originally Posted by Tupelo Kid

Decided to add a little update:

I had to take the MH into CW yesterday for them to replace slide seals or rubber flaps at the top and bottom of the slide.

While there I requested an estimate for installing the 2nd AC unit with a 110 plug. I also asked for an estimate to install the Gen Auto start.

They refused to install either.



Said they had never installed an auto gen start on a MH.

Also said they would not install the AC unit for 110 due to "some" AC's have a 2nd & 3rd start cycle to ensure the unit will start if it fails the 1st time.

Because of this they said most 110 GF plugs in the MH parks would trip and I would not be happy not being able to run the unit.



OH, and they didn't replace the slide seals after I've been waiting for them since Aug 2017 when we took delivery.



I took a detour from the service dept to the GM's office and inquired about this. He was in question about all of this as well.

On the Auto Gen start he said they had installed 2 of these in the past 2 weeks. He said they were both toy haulers but if they can install that they should be able to install in the MH.

He said he would call me in a day or 2.





I didn't know it was this difficult to spend my money.



Sure was easy to spend it for the MH but....

It’s always puzzled me why service people refuse work. Can’t remember how many times I’ve been told (mostly on cars) “that’s normal” or “they all do that” when it’s obvious that something is amiss! I make a mental note and go elsewhere. Good luck.

[thor293]

Originally Posted by Tupelo Kid

Decided to add a little update:
I had to take the MH into CW yesterday for them to replace slide seals or rubber flaps at the top and bottom of the slide.
While there I requested an estimate for installing the 2nd AC unit with a 110 plug. I also asked for an estimate to install the Gen Auto start.
They refused to install either.

Said they had never installed an auto gen start on a MH.
Also said they would not install the AC unit for 110 due to "some" AC's have a 2nd & 3rd start cycle to ensure the unit will start if it fails the 1st time.
Because of this they said most 110 GF plugs in the MH parks would trip and I would not be happy not being able to run the unit.

OH, and they didn't replace the slide seals after I've been waiting for them since Aug 2017 when we took delivery.

I took a detour from the service dept to the GM's office and inquired about this. He was in question about all of this as well.
On the Auto Gen start he said they had installed 2 of these in the past 2 weeks. He said they were both toy haulers but if they can install that they should be able to install in the MH.
He said he would call me in a day or 2.


I didn't know it was this difficult to spend my money.

Sure was easy to spend it for the MH but....

Unfortunately that is the response that seems to be typical for CW. I wont ever spend another dime with them they are absolutely useless. If we were closer I would help you install the unit. Of if you are ever coming to Ohio hit me up!

[Tupelo Kid]

Originally Posted by thor293

Unfortunately that is the response that seems to be typical for CW. I wont ever spend another dime with them they are absolutely useless. If we were closer I would help you install the unit. Of if you are ever coming to Ohio hit me up!

Thanks for the offer.
I appreciate it.
Hopefully I'll find someone within 300 miles (OR a LOT less) and have the 2nd air condition unit installed and the auto generator start unit too.

It's tough to be ignorant but I just can't know everything. (GRIN)

[bgpeters]

Wonderful Thread!

Except for rebuilding my AC units (yes two), I can't wait to apply the ducting and insulating tips!! I'll try to find a way into the front & back end cap too that has nothing... should help sound and heat. Great ideas! Thanks!

For the airflow problem while driving:

Has anyone tried adding a scoop or deflector to each side of the A/C cover? This would help drive air into the case as much as extra fans inside. It wouldn't help gas mileage of course. Has this been tried?

Way way back in this thread there was one guy who pulled his unit at a rest stop and put it back in reversed (since airflow while driving is backwards, see http://www.thorforums.com/forums/sho...0&postcount=72). He reported great success. Has anyone else given this a go? Feels like there must be a good reason RVs are not built this way, since this would be so simple for them with no added cost. Any thoughts on this?

Barry

[bgpeters]

I'll try posting again... (don't know what happened to my 1st try).

This is a WONDERFUL thread. Thank you so much for all the great tips. I have 2 AC units in my Windsport 29M, so I'm already in pretty good shape. Yet, I have a hard time keeping my hands off if I find a way to 'fix' things to work a little better. So, I'm definitely going to take a close look at my duct work and apply the tips here to make it more efficient. Insulating the low pressure portion of the AC is on my list too.

To help with airflow while driving, how about a scoop/deflector on each side of the cover to pull air in and help the condenser cool? Anyone tried that? I know some here have added fans.

Way way back a guy (post #72 in this thread by gmtech16450yz) had pulled & remounted his AC unit backwards to deal with the airflow problem while driving. I wonder why RV manufacturers don't do this as a standard practice? It would not cost more.

[Laco]

As far as icing, we have two Dometic AC's installed in our Gemini, and yes they can and occasionally do ice, but they seen to have their own recovery cycles when that does happen. If I set the thermostats at 77 or 78 they virtually never ice, if I set them for 70 or 71, they tend to ice more often. They also can and do ice when run in the heat pump mode, under the right, or wrong, circumstances.

[Long & Winding road]

Originally Posted by bgpeters

I'll try posting again... (don't know what happened to my 1st try).

This is a WONDERFUL thread. Thank you so much for all the great tips. I have 2 AC units in my Windsport 29M, so I'm already in pretty good shape. Yet, I have a hard time keeping my hands off if I find a way to 'fix' things to work a little better. So, I'm definitely going to take a close look at my duct work and apply the tips here to make it more efficient. Insulating the low pressure portion of the AC is on my list too.

To help with airflow while driving, how about a scoop/deflector on each side of the cover to pull air in and help the condenser cool? Anyone tried that? I know some here have added fans.

Way way back a guy (post #72 in this thread by gmtech16450yz) had pulled & remounted his AC unit backwards to deal with the airflow problem while driving. I wonder why RV manufacturers don't do this as a standard practice? It would not cost more.

Thats, Im glad its helping folks.

I dont think mounting backwards would do any good unless you change the rotation on the fan (The Fan under the roof cover). Its blowing out (on the condenser) to remove heat so the would be fighting each other. But the scoops might help.

I though about changing the plastic cover on mine.... the louvers restrict the outbound air on the back of the cover. Might see a small inpovement there.

IMO, I think with all of the "easy" mods listed here there is no need to add fans or reverse the AC on the roof.

Im happy with my results - No need for 2nd AC on my short 27 foot RV.

[Long & Winding road]

Originally Posted by Laco

As far as icing, we have two Dometic AC's installed in our Gemini, and yes they can and occasionally do ice, but they seen to have their own recovery cycles when that does happen. If I set the thermostats at 77 or 78 they virtually never ice, if I set them for 70 or 71, they tend to ice more often. They also can and do ice when run in the heat pump mode, under the right, or wrong, circumstances.

Good to know. I have not experenced and iceing on my Colman unit. I leave set at 72 deg most of the time. Sometimes I will bump it down to 68 if we are outside then when we come in at night I will turn it up to 74 - 76 so I dont hear it cycle so much when sleeping.

[Laco]

Icing is also very dependent on humidity conditions, virtually never see it happen when conditions are very dry, far more often in humid weather, which is not surprising. I believe you could probably avoid most of it, by continuously running the fan on hi speed, but I dislike the noise associated with that, so live with occasional icing.


I would not suggest changing airflow directions, either for the condenser or the evaporator. Increasing airflow might help, but I certainly would not reverse it.


As far as getting by with a single AC, yes we can, most of the time, but heat build up inside, is dependent, not only on outside temperatures, but sun exposure and the direction of the sun exposure. With ours, even with temps in the 80's, if the front cab area is being blasted by sun, we use the front AC to bleed out that intense heat. If the exposure is from a different direction, even with temps in the high 90's one AC holds it satisfactorily. Its nice to have that second AC available at the touch of a button.

[thor293]

A thought on placing scoops on the AC cover, rather than a scoop look at a racing equipment page for NACA Ducts, less drag, not sure if there is room but as I recall there is. NACA Ducts come in assorted sizes.

[gmtech16450yz]

I'm the guy who turned his AC unit around at a rest stop 30 something years ago. It worked then, and it the theory and physics still hold true today with current AC units.

Guys the "reversing" of the airflow by turning the entire unit around isn't something that's really debatable. And no, you don't have to reverse the fan or anything crazy.

The airflow through the condenser comes IN the back, and OUT the sides. Turn the entire AC unit around and the air now comes IN the front, and again, OUT the sides. Last time I checked there's more air hitting the front of a moving vehicle than hitting the back. haha.

Try this... Stick your head out the window of your RV when it's on the freeway. Look forward with your mouth open. You get a mouthful of air don't you? Now turn your head and look backwards with your mouth open. How much air is going in your mouth now? lol. Same principle.

I have the rear Mach 8 heat pump mounted backwards on my Vegas. I can watch the amperage draw drop when the coach starts moving. I don't care if anyone else turns their AC around, I'm just telling you the facts and results of the idea. It seems most of you are having cooling issues when parked anyway. Turning the AC around does nothing when stopped.

[Long & Winding road]

OH so the fan sucks in and blows out the sides of the AC cover? I thought it was the other way around. SO yeah if it sucks in then reverse mount would works great. I wonder if they install them like they do for two reason: A - areo dynamics (well slightly) and B - so a bird, rocks or bugs dont accumulate in condenser (but bust it up)??

[Long & Winding road]

I thought I would revive this thread since its getting hot outside plus update you on my RV.

Its still cooling great just like it reported last year.

I would do the exact same thing again on ANY RV that I purchased.

Plus the ceramic window tint helps to keep it cool inside ....and you not sitting in the dark with all the windows covered with the ceramic bubble to reject the heat.

But I leave the bubble in the bedroom windows all the time since we like it dark at night (or even for daytime naps).

[mstng]

Learned a lot from this thread. Timely reminder of days when I couldn’t get the temp below 80.
For me the biggest difference came from adding the vent right below the primary blower. I’m convinced the air going through the ducts mix with very warm air because it’s uninsulated. Taping the baffle to separate the cold and warm also made a huge difference. I usually just leave the 1 LR vent open and 2 in the back. I hit the 60’s frequently in the heat of the day in Florida. May not be possible without the bubble film in the front as when I don’t have it it’s very warm at the very front.
Great idea the bubble in the back for room darkening.