Attic Vent in 5er for Full time?

Searching_Ut wrote:
The need for a roof vent can be misleading. My bighorn doesn't have a roof vent because the roof, like the walls are more or less laminated Styrofoam. The air conditioner vents are simply slots cut in the foam. I suppose if and when the foam starts decaying it will start snowing when I turn on the AC.

Thanks for the response, how do you like the Bighorn? This is one of the other models we like but have been wary of because of the roof vent issue? Pros Cons? do you Full time in it? I appreciate your help!

waterboy909 wrote:

Searching_Ut wrote:
The need for a roof vent can be misleading. My bighorn doesn't have a roof vent because the roof, like the walls are more or less laminated Styrofoam. The air conditioner vents are simply slots cut in the foam. I suppose if and when the foam starts decaying it will start snowing when I turn on the AC.

Thanks for the response, how do you like the Bighorn? This is one of the other models we like but have been wary of because of the roof vent issue? Pros Cons? do you Full time in it? I appreciate your help!

Love the floorplan, size a little bigger than I would like, perfect for the wife. Frame, some of the wiring leaves a little to be desired, but that applied to everything we looked at other than the arctic Fox, Outdoors RV line, and they didn't fit us in other ways. Mostly good quality components, fantastic furnace heats fast, very quiet but uses a fair bit of gas. Had to baffle the 18cf gas/elec fridge but works good now. About 5k miles being towed so far and not showing any signs of wear from that yet. We retire in May, and won't be full time but plan extended trips such as Alaska, east coast, Florida etc. Haven't decided what I think of the fully ducted AC yet. Much quieter than any other rig I've owned, but even with two 15k units it struggles a little more than I think it should. Temps were topping 100 when it was struggling though which is tough for any RV. Fair bit of early issues dealer took care of, but seems to be doing good now. Can't wait to get some trips in longer than two weeks at a time

Searching_Ut wrote:
Haven't decided what I think of the fully ducted AC yet. Much quieter than any other rig I've owned, but even with two 15k units it struggles a little more than I think it should. Temps were topping 100 when it was struggling though which is tough for any RV. Fair bit of early issues dealer took care of, but seems to be doing good now.

How is the airflow out of ceiling registers?

Have you measured temps of air return vs cold air discharge?
Should be 18*-20* difference if functioning properly.


Our 34' 5th wheel just ONE 15K ducted A/C maintained 70*F in 100*F high humidity temps but would struggle as temps went above 100*F

TWO 15K A/C Units should be chilling.

Unless they are passing (leaking) air between return/discharge or issues with duct work restricting air flow

My 2012 and my newer 2015 Montana is vented I would go up on the roof and tell ya where the vents are but it is Raining hard right now (on the Wash Coast) SHOCKER!:B and yes they help I am a fulltimer for 6 years now in both of them and the only mold I get is the a little in the Bedroom closet and I use a little Dri-Eze and all is good

Old-Biscuit wrote:

Searching_Ut wrote:
Haven't decided what I think of the fully ducted AC yet. Much quieter than any other rig I've owned, but even with two 15k units it struggles a little more than I think it should. Temps were topping 100 when it was struggling though which is tough for any RV. Fair bit of early issues dealer took care of, but seems to be doing good now.

How is the airflow out of ceiling registers?

Have you measured temps of air return vs cold air discharge?
Should be 18*-20* difference if functioning properly.


Our 34' 5th wheel just ONE 15K ducted A/C maintained 70*F in 100*F high humidity temps but would struggle as temps went above 100*F

TWO 15K A/C Units should be chilling.

Unless they are passing (leaking) air between return/discharge or issues with duct work restricting air flow

The air cools down good as indicated by the IR gun, while air flow seems like it could be higher considering only 3 cold air vents and 3 return vents in living room area. As mentioned, I'm still undecided on how good it works. Most camping we've done so far with this rig has been boondock or 30 amp service where it was only getting up to 90's in day. We were camping longer term in these areas and AC had no trouble holding it's own. When we hit the hot areas we were traveling in the day, no hookups till afternoon. Seemed to struggle to get it cooled down even with two AC units. Only thing I can compare with though is much smaller TT's with considerably smaller air volume and surface area to cool down.

Searching_Ut wrote:

Old-Biscuit wrote:

Searching_Ut wrote:
Haven't decided what I think of the fully ducted AC yet. Much quieter than any other rig I've owned, but even with two 15k units it struggles a little more than I think it should. Temps were topping 100 when it was struggling though which is tough for any RV. Fair bit of early issues dealer took care of, but seems to be doing good now.

How is the airflow out of ceiling registers?

Have you measured temps of air return vs cold air discharge?
Should be 18*-20* difference if functioning properly.


Our 34' 5th wheel just ONE 15K ducted A/C maintained 70*F in 100*F high humidity temps but would struggle as temps went above 100*F

TWO 15K A/C Units should be chilling.

Unless they are passing (leaking) air between return/discharge or issues with duct work restricting air flow

The air cools down good as indicated by the IR gun, while air flow seems like it could be higher considering only 3 cold air vents and 3 return vents in living room area. As mentioned, I'm still undecided on how good it works. Most camping we've done so far with this rig has been boondock or 30 amp service where it was only getting up to 90's in day. We were camping longer term in these areas and AC had no trouble holding it's own. When we hit the hot areas we were traveling in the day, no hookups till afternoon. Seemed to struggle to get it cooled down even with two AC units. Only thing I can compare with though is much smaller TT's with considerably smaller air volume and surface area to cool down.

Can't get accurate air temps using an IR Gun.

Need a regular thermometer, stick it in discharge duct (closest one or even better right in discharge plenum if you have 'chill grill') and leave it in for a few minutes.

Do same for return air side.

What is the difference between the two?
18-20* A/C is working great

Lower differences......then check if discharge air and return air are mixing -----plenum not properly sealed off