Forum Discussion
JaxDad
Apr 07, 2017Explorer III
dougrainer wrote:JaxDad wrote:ArchHoagland wrote:
Always close the roof vents and windows when you are running the air conditioning whether it be parked or moving down the highway.
The air conditioners bring their air in from the interior of the coach. If you leave the vents open then you are drawing in hot air.
Actually that's wrong.
Unless the dash a/c is set to 'max' or 'recirculate' the system cools outside air and vents stale air. All vehicles operate this way.
As for cooling efficiency, if you leave the rearmost roof vent open (hot air rises) and set the dash a/c to highest fan and set to blow down the back the hotest air will be drawn out the roof and the cooled air will be drawn towards the back to cool the rest of the coach.
I've been doing this for years and have proven how well it works to many non-believers over the years.
On a typical dash unit the blower fan is the weak part and it usually can't keep up with the cooling capacity of the rest of the system. This method dramatically increases air flow and really helps.
Maybe in Toronto you can use the Dash AC to cool a 30 foot plus Motorhome. BUT IT WILL NOT in the rest of the world.
Doug
No, on a 40'er it probably won't keep up, but on a 30'er, especially a C on. Ford chassis it sure will.
The Ford dash unit is far more powerful than a rooftop unit is.
It's also a LOT more fuel efficient than running the genset to run a rooftop unit is.
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