Air Conditioning / Heating

Uncle Rog

Well-known member
All RV units need to be equipped according to size.........
This is an obsevation, not a gripe, after 3 seasons of owning our rig................
We love or rig, I mean we really like the BH.
This is our fourth RV and hands down the horn is head and shoulders above the rest.....................by far.
I have tried Timk's "tent in a vent", and just about every other fix you can imagine, and have come to the conclusion that, realistically, above 85F the 13.5BTU AC unit, in the ducted ceiling, is not sufficient for the 3600RL.........Period.
We do have a second unit in the bedroom but I only installed a 30A, RV type, electric supply for the unit(s) at the compund where we re-supply. It is only 96F today and it is 90F in the horn, momma is not real excited about getting things set up, no bueno. We will not be taking an imprompto trip for firecracker day.
The heater works really well when it is not cold, not sufficient for any thing less than 40F.......................
I have gone back through some of our old paperwork and all of the rigs we have owned have had the same size AC and heater units...........
The first 24', the horn 36'+................
Our plan is to abandon the suburban heater for a wall type of vented catalytic unit and convert the AC to an internal ducted system that is not
subject to the super heating of the roof surface..........
I have compared insulation, construction, fit and finish, good looks, ease of appliance access, and even drinkability and the BH wins on all accounts..............................
We just need to tool up the unit to our environment..............

HAPPY 4TH OF JULY!!!!!!!!!!!!!!!!
 

fhollan

Well-known member
Vents!

Uncle Rog: Before I implemented timk's invention, I inspected all the vents by taking off the covers. What I found was that just about all of them weren't sealed right. A majority of the air was going between the ceiling and the roof. So I sealed them. I then implemented timk's idea. After that I installed a digital thermostat. Now I've got quite a bit of cool air coming out of those vents. Earlier last month the temperature creeped up in the low nineties with high humidities. It kept the rig very comfortable inside. If you haven't inspected the vents yet, you might do so and make sure there aren't any kinks holding back air flow. I do not have a A/C unit for the bedroom. I hope this helps!
 

TXBobcat

Fulltime
I have a 2008 3400RE Bighorn. It will keep about a 20* differential. I don't have timk's mod installed. I may do it later, but one thing... It does keep the toilet room COLD. We have a 13.5 in the bedroom and it will take it down to 65* at night, which is its limit.

We lived in Texas and it has worked well for us..

BC
 

Uncle Rog

Well-known member
Thanks guys, Frans might have a point about the ducting, another good project for me. We did experiment yesterday by firing up the BR unit and opening the main unit to blow straight into the rig. With the ceiling fan on both units ran off the 30A circuit and it did keep things pretty comfortable. The outside temp was 95* and the horn was right at 80*, much better than Thursday.......................
 

yondering

Retired-Full Timer
We have a 2009 3580RL Bighorn with 15,000 main and 13,500 in bed room. Here in Texas, temp right now is upper 90's, and with both units running the inside temp is 78, a little warm, but comfortable. I checked vents and found all sealed well. plenty of air flow through out coach. hope you find a working solution to your heat up problem. God Bless ya, Al
 

busted2341

Well-known member
Hey guys...Just woundering how to check for seal in the ducting. I did not do the tent in vent mainly because I am not qualified to figure that one out! Anyway, I have now realized my grand idea of saving money with just the one A/C was.....not correct, sorry ladies just won't say it, and will be adding the other in the bedroom this week before heading back to the Texas Coast. Was woundering how to make sure ducting is sealed and should I have a force air A/C in the bedroom or have it run into the ductwork already there?
 

jbeletti

Well-known member
Busted,

You won't be able to connect the bedroom AC into the exiting duct system. So it will have to be "down draft" only.

I think the duct sealing most people are doing are in two areas. The air box and the duct openings. They use metal foil flashing tape. You can get it at any hardware store, building center or Camping World.

The air box is an area under the large square white grill at the ceiling. Here are some tips on flashing the air box a little better if needed. This pertains to the Dometic brand of AC. Not sure if the Carrier can be done the same way.

  1. Turn the air conditioner off
  2. Remove the filter/grill
  3. Remove 2 screws in that area
  4. Then on two outer corners, look for small round plastic caps, pry them off and remove 2 more screws. The entire white plastic assembly will come off then
  5. Note that there are 2 chambers in the air box. One is for return air and one for cooled air. Whatever is used to separate these two chambers, is usually stuck in place with double-sided tape. You need to flash around the seams of this divider so air cannot flow between the two sections
  6. Also, look up into the output side. To each side, you will see a rectangular box end that is the duct system that goes down each side of the RV. Look at the edges of these ducts where they come into the chamber. Flash around the edges tightly to smooth things out
  7. Replace grill, filter, screws and caps
  8. Okay to turn air conditioner back on now :)

The duct openings in the ceiling is another area some customers focus on. I have never done this but my sense is that you approach it as follows:

  1. Remove screws that hold the round plastic ceiling grills in place
  2. Carefully pull down on the grill to remove it
  3. Observe the round hole cut in the ceiling panel and then into the duct box. This joint between these two materials is what I believe most people are flashing. Using the flashing tape again, seal this joint well
  4. Replace grills and screws

My input above is from my experience and from what I have read. It is not to be construed as any official Heartland response. I know others will weigh in here with their own experiences. Take what you can from it and tackle it.

Jim
 

SmokeyBare

Well-known member
Jim,

As always... your information is very good ! I have done both tasks you mentioned. I felt that I eliminated some areas where my valuable A/C Cooled air from reaching places it did no good... such as above the ceiling. It also in my view increased the volume of air flowing through the A/C Grills and into the living space of our BigHorn.

I have also taken it one step further by placing a block at the end of each A/C Duct Run, just past the last Ceiling Vent. I did this only to prevent any air from escaping the end of the duct work... although I couldn't really tell if there were any leaks there... but it did give me a little peace of mind.

The most recent job I have tackled started out by cleaning the Screen in the bathroom Ceiling Fan/Vent opening. To do this I needed to remove the inside cover... doing so I seen where the duct work on the door side of the RV ends. The A/C duct was right behind the plastic trim of the ceiling fan/vent. I noticed the tape sealing the end of the A/C Duct was lose... allowing air to escape into the bathroom... which is always very cool when the A/C is running. I sealed this area with the foil tape... and I believe this will once again reduce any cool A/C air from leaking into un wanted areas.
 

busted2341

Well-known member
ok....thanx for the info...I will once again attempt to correct some of my lost air. The rear two vents in the living room just don't seem to be putting out much air. Hope it's simple for "me" to fix....thanx again
 
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