Using coach air instead of dash air when traveling?

[Jstarwal]

When buying our new to us 1999 Coachmen leprechaun, from a private party, they told us that they use the generator and coach air instead of the dash air because it was cheaper.
What's your thoughts?

 

[ArdraF]

Yes, most of us who live and/or travel in the desert southwest, often use our roof air for cooling.  Most of the dash air conditioners are inadequate and can't begin to keep up with cooling something with the interior space of an RV.  Also, have you ever seen a highway sign at the start of a long upgrade warning people to turn off their air conditioners?  That's because the a/c puts an extra load on the engine and you want to avoid the engine overheating.  By using the roof air, you don't have to worry about the engine working too hard.  Finally, you'll be using the generator to run the a/c which is good for the generator because it needs to be used frequently with a load on it, in this case the a/c.

ArdraF

 

[Wizard46]

ArdraF is correct but I will add that if it gets hot enough, we will use both at the same time. That way Patsy can set hers for the back and I can set mine up front. She usually sits in on the couch with Taz and Jake sits up front with me.

Jerry

 

[Jeff Brown]

We live in the southwestern desert and manage to get by pretty well with just our dash air, but I dont hesitate to fire up the Genny if the dash unit is having a hard time keeping up.  As far a fuel consumption I dont know how much extra strain the AC belt adds to the motor but the Gen running costs us just under 10% in fuel mileage consumption.  I personally didnt pay all that money to travel comforably to be foolish and not be comfortable for what amounts to just over a buck an hour for roof air.  (That math assumes $5 per gallon and .75 gal per hour consumption, YMMV quite literally!)

Jeff

 

[Jstarwal]

Thanks for all the info. I guess that answers my question.

Jack

 

[Gary RV_Wizard]

A single a/c puts a load of about 1kw per hour on the genset. For most generators, that amounts to less than 0.5 gal/hr and perhaps as little as 0.2 gal/hr. That's around $1.00-$1.50/hr at todays fuel prices.

It's harder to see the effect of the dash air on the big engine and mpg, but its there. A dash a/c compressor uses  5-10 hp and may run only part time on a mild day but full time when its hot. That's an extra load that takes extra fuel,  even though it seems "free".

 

[Campfire RV]

I'm glad I came across this thread. I was wondering about the same thing since we are going to the dealer in the LA area to pickup our new MH then drive it back home in the desert.

Also, have you ever seen a highway sign at the start of a long upgrade warning people to turn off their air conditioners?  That's because the a/c puts an extra load on the engine and you want to avoid the engine overheating.
ArdraF

I have seen my share of those signs living in the Mojave desert, especially traveling to Death Valley.

 

[vsheetz]

It's been many years since the dash air on our MH stopped working - big dollars to fix, so we just use the genny and roof air.  Added a undercounter fan in the kitchen to help push the cool air to the front of the coach - also handy for when cooking and the kitchen area gets warm.

 

[AndyinLexington]

Personally I use whatever air conditioning I need to in order to get comfortable.  With all the expenses of RVing taken into account, we're spending between $250 and $300 per day to be out there RVing.  I'm not going to be hot and miserable because I don't want to spend a few more $$ running the generator or the engine driven a/c compressor.  I know that cost is a consideration in everything that we do, and if/when I can't afford it anymore I'll quit RVing.

 

[scottydl]

It's been many years since the dash air on our MH stopped working

Same here, genny + both roof A/C's while driving work GREAT to keep the entire coach cool.  When we bought our coach, the previous owner said the dash air was a little weak and "needed a recharge" ... I've never bothered.  The front dash vents are tiny and I can't imagine that it would cool much even if it did work.

The key to a cool interior while driving (especially in a Class A on a sunny day with all those big windows) is PRE-COOL ... we start our A/C running at least an hour before shoving off, so it's plenty cool when starting.  If you wait until the interior is already hot from engine heat and greenhouse-effect radiant heat... the A/C will never be able to keep up.