2008 Journey basement a/c

[Amy1918]

Should my basement A/C be able to keep my coach cool when it’s 90 outside? This past week the temps were high and my system couldn’t cool down past 84 until the evening.

[wahoonc]

From my understanding the hotter it gets the less effective they are. Several people with basement units have added a roof or portable unit to help cool things off. Mine has 2 13.5k BTU rooftop units and if I can hold 10-15 degrees below outside temps in full sunlight I consider it a win.

I would think you should be able to get 10 degrees below outside temps.

Aaron

[Morich]

RV are something that often require some "tricks" in operation to get past high temps.
One problem is that they are built lightweight and that means thin walls, floor, etc.
with lots of glass and many air leaks!

Some ways to cut heat load is to get as much shade as practical, cut heat producing actions like cooking and showers during the hottest parts of the day.
Looking the RV over and asking where heat is likely to get in is another item. Vents can be helped by adding pillows of insulation of most any type. Covering the windows which radiate so much is a big one, too.
Location is also a big thing that many experienced RV folks consider when they travel.
Go North and higher is a common one for summer.

But all of that aside, we may be reaching a point in history when we have really let things get way out of control!
We are working a science problem with politics!
First we have to admit there IS a problem when the weather gets this extreme but we will likely handle it like we do many large problems!

The English had a saying about our response to WWII?
The Americans always do the right thing. But only after they try everything else first!

[creativepart]

We have two rooftop A/Cs and when temps surpass 93 degrees the RV will eventually heat up to ~80 inside.

The key things to help are to have a good shade on the front window ALL THE TIME the sun is coming in. The window shades are down, and any fan openings are blocked with insulation or fan pillows.

Start the day with it dark and cold as possible and make sure to not park with the RV pointed into the sun especially in the afternoon. Put the awnings out if possible too.

Your RV is very poorly insulated for hot or cold. And your A/C can only do so much. Especially if it's 16 years old.

[Ray,IN]

Yes when both compressors are operating it will keep your MH cool all day. First, look at the amperage draw on the EMS display, you must be on 30A shore power to do this.
When both compressors are operating, plus the fans, you should see the display show 23-26A. If only #1 compressor is running it will read 11-14A.
If only #1 is running, you can shut off the breakers for both compressors and switch the wires in the electrical box to switch their positions; #1 and $2 swap positions.
Then if #1 compressor fails to run you know the Actual #2 compressor has failed.

Your units data sticker is on the left end of the cabinet, you might have to get creative to read the sticker with the model#. Most likely it's a model 6535 A/C/heat pump.
Once you tell us the model# we can supply further help.
I hope that is clear and easy to understand.

[creativepart]

Originally Posted by Ray,IN

Yes when both compressors are operating it will keep your MH cool all day. First, look at the amperage draw on the EMS display, you must be on 30A shore power to do this.

Ray, did you mean “you must be on 50 amp shore power” for both compressors to operate??

[be happy]

My 07 Meridian with basement air will keep it cool. The last few days I have been in Iowa with the temps in the high 90.s and the coach was around 75ish.

I will say that hooked up to 50 amp I get better proformance than at 30. I am not smart enough to say why.

Now with all of that being said there are a couple things you can do to help keep the coach cool. One is to get reflective material for the big magnifying glass we call a windshield. The DW went to a fabric store and purchased some very reflective material and made curtain for the front. The front door window also is a big source of heat that should be covered. I have found that putting the awning out will help keep the side of the coach cooler thus help with the inside temp. Get or make inserts for the roof vents, not so much the bathroom one but the one in the main part of the coach. And last for me is get some floor fans to help with the movement of air. I did the fan thing this trip and was amazed at how will it help.

Good Luck

[Ray,IN]

Originally Posted by creativepart

Ray, did you mean “you must be on 50 amp shore power” for both compressors to operate??

No, the EMS display will not display current amp-draw when on 50A power, you must use 30A to see the amps displayed..
If you have any other electrical draw besides the basement 2-ton/both compressors running on 30A service, the EMS may turn off #2 compressor, if that happens you will see the small light beside the #2 compressor listing is off.
If you want to view the amp-draw of each compressor when on 50A service you must use a clamp-on ammeter at each of the main legs entering the basement unit electrical box..

[Oldchinahand]

As much as it pains this knuckle dragging old flange head to say so , I think Army's assessment of the 30A vs 50A diagnosis is on the mark.

Our basement air is well maintained and recently overhauled. There's not a straight cooling curve , but, generally, below 100 we see in the high 70's. Above 100, it tracks about 20 degrees below ambient.

There are steps we take to mitigate the heat. Several mentioned already.
We travel spring and fall. We just observe the snow birds, and go the other way.
When it's hot, we bring in the slides -- less volume to cool -- less surface area to heat. (The same helps us stay warm while watching the snow fall.)
We rig sunshades on the OUTSIDE (google "how is heat transferred") of that big 16ft picture window in the front. All other windows are tinted to the max of Arizona law. We also have the standard inside window shades.
Wind permitting we rig all awnings.
All cooking done outside.
We try to avoid those sterile parks with six foot wannabe trees.
We try to park facing east. Cooler mornings when its hot, warmer when its cold.
Finally, we endeavor to be home by early June. Heavily coat our noses with zinc oxide and have that be the only body part above pool water line until mid Sept.

Fair Winds and Following Seas

[Ray,IN]

Originally Posted by Oldchinahand

As much as it pains this knuckle dragging old flange head to say so , I think Army's assessment of the 30A vs 50A diagnosis is on the mark.

Our basement air is well maintained and recently overhauled. There's not a straight cooling curve , but, generally, below 100 we see in the high 70's. Above 100, it tracks about 20 degrees below ambient.

There are steps we take to mitigate the heat. Several mentioned already.
We travel spring and fall. We just observe the snow birds, and go the other way.
When it's hot, we bring in the slides -- less volume to cool -- less surface area to heat. (The same helps us stay warm while watching the snow fall.)
We rig sunshades on the OUTSIDE (google "how is heat transferred") of that big 16ft picture window in the front. All other windows are tinted to the max of Arizona law. We also have the standard inside window shades.
Wind permitting we rig all awnings.
All cooking done outside.
We try to avoid those sterile parks with six foot wannabe trees.
We try to park facing east. Cooler mornings when its hot, warmer when its cold.
Finally, we endeavor to be home by early June. Heavily coat our noses with zinc oxide and have that be the only body part above pool water line until mid Sept.

Fair Winds and Following Seas

[Scotty B]

Love all of the replies and agree with the sage advice, though sometimes the suggestions might not be practical. I suppose if you went the same places most of the time during the same time of year, you can ensure that your home when it's too hot and your facing the correct compass location.
However, you're not going to see some beautiful locations only during the winter...Glacier, Great Sand Dunes, Eastern portion of Yosemite, and Great Basin come to mind, let alone Canada.
I've always wondered if the big Diesels cooled better - does not sound like it.
It's 100 degrees here and all of the sites face north west so sun is off our front left quarter in the afternoon.
The ac's are pumping out air in the mid-50's, but the coach thermostats are at 80. No real shade and now out of the Sierras so no mountains to ensure an earlier goodbye to the sun.
We always check average temps when we plan travel. Average temps and conditions are pretty much meaningless any more. It's supposed to be 90 and 60. It's 103 and 75.
We do pretty much everything suggested that we can control in the coach, but basically from 3:00 to 8:00 your just baking waiting for sunset.
The world is on fire and radiant heat is so powerful.
Here are a couple examples. We ran the generator and ACs on the way here yesterday. Arrived around 2 and temp in the coach was 75 in front and 74 in the back. By the time we checked in, parked, leveled, and plugged in it was in the mid-80's.
The water hose and conditioner get so hot you don't need any hot water. In fact, you have to run the cold for a while before it's cool enough to use.
We almost got one of those outside covers you can see through two years ago after late August in Moab, but never needed it or anything close as we traveled across Canada last year. We might look again.
I did buy one of those cheap windshield shades today that you see in cars. I'll let you know if it helps.
Safe travels and good luck staying cool or in the pool!

[Scotty B]

We're so used to being able to control our environment! Really hard when we can't! I mean really, I have to deal with 80 degree temps for a little while??? I guess the bigger anxiety is "is something broken or will something break?"
Travel is transformational...

[Ray,IN]

At most RV walls have 2" insulation.
A small well-placed fan pointed up at about 45° really helps with cooling and heating in extreme temperatures.
FWIW, my RVP model 6535 can maintain 72° inside our MH in 100° outside air temperature.
The "trick" is to never open windows in extreme weather heat, this allows ambient humidity to permeate everything fabric and/or stuffed inside the RV. Then when you turn on the A/C, which must de-humidify the interior while cooling the air, it's already behind the curve for cooling.
This has become so commonplace, some new RV's are made with windows that don't open and are smaller is size.