Motor home ac problem

[Candhill]

We have a 2002 gulfstream motorhome. Ac works great when sitting still and generator is running. Traveling down the road the temperature inside the coach climbs to about 85. The units have been cleaned, the air coming out stays about 20 degrees lower than the return air. But the middle of the coach is hot! We don't know what else to try. Any ideas?

[Hank_MI]

wa8yxm wrote:
I was telling folks her there are Some problmes that Rachael (THE RV GIRL) can not fix.. Oh she can fix most anything between the ROOF (and what's on it) and the Chassis other than engine and drive train, but there is one part she can not fix.

NOW. for the record the OP is not ... Quite.. There yet.. But read this one

Poster says it's 110 out. A/C is holding 85 in but when he turned on teh Fantastic Fan it went UP To 90... Think about it folks no matter which mode the FF is in is sucks in outside (110) air.

Now the problem here is you think your house is all sealed (unlike his) but the fact is there are many small air leaks,, Under slides. Holes that let pipes and wires in/out and so on.. When driving the RV is sucking inside air and getting warmer.

I have absolutely no idea what you just said. Which poster said it's 110. Who mentioned a fan? Who is Rachael? You totally lost me.

[wa8yxm]

I was telling folks her there are Some problmes that Rachael (THE RV GIRL) can not fix.. Oh she can fix most anything between the ROOF (and what's on it) and the Chassis other than engine and drive train, but there is one part she can not fix.

NOW. for the record the OP is not ... Quite.. There yet.. But read this one

Poster says it's 110 out. A/C is holding 85 in but when he turned on teh Fantastic Fan it went UP To 90... Think about it folks no matter which mode the FF is in is sucks in outside (110) air.

Now the problem here is you think your house is all sealed (unlike his) but the fact is there are many small air leaks,, Under slides. Holes that let pipes and wires in/out and so on.. When driving the RV is sucking inside air and getting warmer.

[mph_medic]

We have the same problem ,, dash a/c doesn't work so when we travel we run the generator and the front A/Cand we bought a blower/fan from sams it looks like a carpet blower with a rotating head and really puts out air.. we place it in the middle of the coach and it works,, hope this helps..

[dougrainer]

Motorhomes have inherent vacuum leaks in transit. That means they will suck in outside air. You have a major source of outside air gaps somewhere in your motorhome. You need to open up cabinet doors and cabinet floor panels to find the source. A usual source is the area where the fresh water/Black Water tank system is located. They sometimes do not seal off the holes cut thru the floors for the plumbing. Another source if rear engine Diesel is the back wall area and the hot engine heat is drawn in thru the various gaps that were not correctly sealed. One way to determine where you have the gaps is to find a Service Center that has a smoke machine to fill the interior with pressurized smoke and then find the areas where the smoke comes out. Doug

[turbojimmy]

Candhill wrote:
We have a 2002 gulfstream motorhome. Ac works great when sitting still and generator is running. Traveling down the road the temperature inside the coach climbs to about 85. The units have been cleaned, the air coming out stays about 20 degrees lower than the return air. But the middle of the coach is hot! We don't know what else to try. Any ideas?

When you say the air coming out stays 20 degrees lower than the return air, is that while you're in motion? You have good, strong air out of the vents while moving? If so, that's an odd issue. My '84 Allegro has more air leaks than water leaks (and it has a lot of water leaks) but the one thing is does well is stay cool while in motion. I don't have chassis A/C but the 2 roof units keep it fridge-like cold while moving. It sounds like you're losing a lot of air somewhere, or somehow the air flow is changing somehow while you're in motion.

[want-a-be]

Sorry read the post wrong

[MrWizard]

dash a/c on max air {recirculate} no outside fresh air ?

all roof vents closed ?

what about brake and gas pedals, any outside hot air comming in there

any opening to the outside that allows hot outside air in while driving will pressurize the RV and push your cool air out thru any vents or windows that do not close tightly

two roof top a/c or just one
for (2) close front vent of roof a/c vent let it blow cool air back toward the middle
dash a/c can cool the front seats

its possible you might have to seal the roof a/c with some alu duct tape

[MountainAir05]

Ensure you don't have a vent open/crack in the bath, if that is the area that is getting hot. I would think that hot spot is where air is leaving the Rv when you are going down the road. Are the outside air vents closed in the dash system.