Newbie Question: Motorhome in the Heat

[nwood488]

Hello,

We just bought a 2016 Thor Majestic 23A recently and will be driving across country with our family as we move from the West Coast back to the South. One of our stops is going to be in the Phoenix area for a couple days.

Obviously, we have a working AC in the coach. I am just concerned with the 100-102 heat and what that is going to be like if we don't have any other source of air conditioning.

What should we expect? Should we get a portable AC?

Any suggestions are appreciated!

[paulhead]

The AC in my unit cranked fine in 90* weather the other day, you should be ok with yours.

[Grumpy Grampa]

Keep the coach cool 76-78 inside .Don’t let it get to hot inside harder to cool down.

[MJC62]

If it gets too hot in the coach during the heat of the day you can also start the truck and run the cab air as well. The V10 at an idle with the A/C running will use around 1/2 gallon of gas an hour.

[Pillbox]

Remember you can run the generator for the a/c while driving. This should help keep things a little cooler. Once it gets hot inside……well its hot.
Terry

[Lt Keefer]

When it is over 100 degrees outside the inside of your RV will be hot, even with the A/C running full speed. It is an RV and has minimal insulation. The best you can do is find the shadiest camp site and set the thermostat so that it runs 24 hours a day.

[Elite Washington]

Living on the west coast you know it’s always hot during the summer you should be fine at a 102. Just leave the AC on but don’t crank it way down so it freezes up. Leave the AC on all day running the generator. Use the cab AC to help keep it cool. Last summer we were camping in central Washington when it was 110 out and had molding melting but inside was nice and cool. Phx will still be cool at night this time of year it’s not miserable until summer at night.

[nwood488]

Would you all recommend a portable AC in this kind of weather or just keep the AC in the RV going the entire time?

[saddlesore]

Personally I would just use the AC 's you have,

[Elite Washington]

Originally Posted by saddlesore

Personally I would just use the AC 's you have,

We have been fine with just one AC. If you have a portable AC that you can bring then that won’t hurt. But I wouldn’t go out and buy one just for a couple of days in Phx.

[ducksface]

An Arizonan's input:
Don't plan on it shutting off until maybe midnight if you're parked in a pavement bound rv park or on a paved road. You might hit a cool week and I'll be wrong. I wouldn't bet on it.

10 minutes turned off during the day will negate the gains you made/heat you staved off in the past 10 hours.

105° is a temp taken in open air, in shade, at 5ft off the ground. That 105° is what they'll tell you officially. 10 iches off of pavement and 11ft off the pavement in full sun...that's you.

Your roof and the pavement will be ssssooooo much higher. Untouchably higher.
The low temps are now mid 70's .
Mid 70's air temp can only pull a measured amount of the 160° roof temp away.
If it's windless your rv will form a heat barrier around itself.
If the nightly low temp pulls 90% of your heat away, can you live with 80° without ac at 4 am?

Do not park facing west.


Run your dash air too.
.67 gallons an hour for our v10.
That's 14ish gallons in 24 hours.
It might be a consideration to buy that portable ac unit...

Pessimists are almost always pleasantly surprised but sometimes only break even.
Optimists are disappointed as often as they break even.

I'm a bit pessimistic about Phoenix wrather(Phoenix doesn't have weather. It has wrather)being forgiving.

And
That portable ac can be used in your new home for years to come. We have one for the spousal units 24x20 shop. It's one cash outlay to ensure comfort for many many years. Err for you and yours. Don't bet against yourself.
And
Texas and New Mexico can be just as miserable as phoenix.

[Elite Washington]

Originally Posted by ducksface

An Arizonan's input:
Don't plan on it shutting off until maybe midnight if you're parked in a pavement bound rv park or on a paved road. You might hit a cool week and I'll be wrong. I wouldn't bet on it.

10 minutes turned off during the day will negate the gains you made/heat you staved off in the past 10 hours.

105° is a temp taken in open air, in shade, at 5ft off the ground. That 105° is what they'll tell you officially. 10 iches off of pavement and 11ft off the pavement in full sun...that's you.

Your roof and the pavement will be ssssooooo much higher. Untouchably higher.
The low temps are now mid 70's .
Mid 70's air temp can only pull a measured amount of the 160° roof temp away.
If it's windless your rv will form a heat barrier around itself.
If the nightly low temp pulls 90% of your heat away, can you live with 80° without ac at 4 am?

Do not park facing west.


Run your dash air too.
.67 gallons an hour for our v10.
That's 14ish gallons in 24 hours.
It might be a consideration to buy that portable ac unit...

Pessimists are almost always pleasantly surprised but sometimes only break even.
Optimists are disappointed as often as they break even.

I'm a bit pessimistic about Phoenix wrather(Phoenix doesn't have weather. It has wrather)being forgiving.

And
That portable ac can be used in your new home for years to come. We have one for the spousal units 24x20 shop. It's one cash outlay to ensure comfort for many many years. Err for you and yours. Don't bet against yourself.
And
Texas and New Mexico can be just as miserable as phoenix.

Having lived in Texas and Arizona, I can say for certain a 90 day in Dallas is always worse then a 117 day in Phx.

[LarryD]

This is a topic dear to me as I am sensitive to heat having had a heat stroke in the Army. I'd follow the advice of others running both house a/c's and the coach a/c all during the day. When stopped and in the sun keep all the shades down and your windshield covered. You will be astonished at how much heat comes thru your windshield. It's likely not possible now but inspecting your a/c duct work for open ends is one of the best solutions for making sure your a/cs are not just pushing cold air out into the body of the r/v instead of inside the cabin. We use our 2021 Thor Magnitude mostly at the beach and it can still get warm in there during the hottest part of the day. So much so that I'm considering upgrading both roof top units and or buying an Ecoflow portable unit to supplement. Good luck.

[The Gritz Carlton]

Originally Posted by LarryD

This is a topic dear to me as I am sensitive to heat having had a heat stroke in the Army. I'd follow the advice of others running both house a/c's and the coach a/c all during the day. When stopped and in the sun keep all the shades down and your windshield covered. You will be astonished at how much heat comes thru your windshield. It's likely not possible now but inspecting your a/c duct work for open ends is one of the best solutions for making sure your a/cs are not just pushing cold air out into the body of the r/v instead of inside the cabin. We use our 2021 Thor Magnitude mostly at the beach and it can still get warm in there during the hottest part of the day. So much so that I'm considering upgrading both roof top units and or buying an Ecoflow portable unit to supplement. Good luck.

What would the upgrade be? Both units are 15K BTU, right? I've had no issues being frozen out in any situation we've been in so far. Frying eggs on the hood but wife wearing light sweaters inside. Agree with a previous comment...stay ahead of it...crank them up early and keep them going. The dash unit keeps the coach comfortable while underway. If its really hot, I'll fire up the generator and run both rooftops about 30 minutes before we get to campground that evening but, never have really suffered from heat. Regarding the Phoenix stop...I'd keep moving a few hundred more miles. I've placed towels along the floor at the base of the big slide occasionally...a lot of cold air seeps out there.

[Scubawise]

Amazon has a roll of material similar to car window sun screens. We cut for all windows and do issues keeping cool

Reasonable price per roll and get A/C Tape to do all edges

[LarryD]

Originally Posted by The Gritz Carlton

What would the upgrade be? Both units are 15K BTU, right? I've had no issues being frozen out in any situation we've been in so far. Frying eggs on the hood but wife wearing light sweaters inside. Agree with a previous comment...stay ahead of it...crank them up early and keep them going. The dash unit keeps the coach comfortable while underway. If its really hot, I'll fire up the generator and run both rooftops about 30 minutes before we get to campground that evening but, never have really suffered from heat. Regarding the Phoenix stop...I'd keep moving a few hundred more miles. I've placed towels along the floor at the base of the big slide occasionally...a lot of cold air seeps out there.

Not positive but I thought they were 13k. I'd "upgrade" to the largest possible without having to cut or modify. From the very little research I've done the stock units are neither the largest nor "best" in class that would seem to fit with nearly zero effort. I'll do another summer with them before making a decision.

[Scubawise]

Originally Posted by LarryD

Not positive but I thought they were 13k. I'd "upgrade" to the largest possible without having to cut or modify. From the very little research I've done the stock units are neither the largest nor "best" in class that would seem to fit with nearly zero effort. I'll do another summer with them before making a decision.

This really helps in winter and summer..
Tested on the road 7 months in 23 states ..I think

Regarding the Phoenix stop...I'd keep moving a few hundred more miles. I've placed towels along the floor at the base of the big slide occasionally...a lot of cold air seeps out there.

[txc2936@yahoo.com]

Only expect to have the cabin about 20 deg lower than outside temp. So at 102 deg outside, you are going to get maybe 80. As above, start the AC early in morning and keep it running thru the heat of the day. Waiting for all the furniture, etc to get to 100 and then trying to cool, isn't the method. To start the cycle, i start engine AC full blast and run generator with both AC units running. I have the 50 AMP service on this AC, with the big ONAN 5500 Gen. That helps alot, also, run floor fans to circulate airflow in RV. Think about it as trying to extract the heat out of everything in the RV.

[Scubawise]

We open all windows and vents early morning..run maxair to pull cool air..then A/C UP

[txc2936@yahoo.com]

Only thing i noticed stepping up to the THOR ACE and FORD 53 chassis,. We owned the Chevy Freedom Elite and the Chevy blew ice cubes. Seems like the F53 doesn't have the cooling output the Chevy does. i can put a thermometer at outlet see if its close to 57Deg F.