Alpine 3712KB AC issues

[Troy965]

I'm in Louisiana and I run both of my 15,000 btu ac's on high and RV will not stay cool during the day

[chuckster57]

When do you start the Ac’s? Sometimes you need to start them early on. Exterior color and how much shade your parked under will have an affect.

[Troy965]

My home was list in Hurricane Ida . I've been living in my RV for 6 months while rebuilding so the units have been running. I have a relative who has same floorpan in a forest river sandpiper and his RV stays cool

[chuckster57]

Originally Posted by Troy965

My home was list in Hurricane Ida . I've been living in my RV for 6 months while rebuilding so the units have been running. I have a relative who has same floorpan in a forest river sandpiper and his RV stays cool

Sorry you lost your home. Are the exterior colors the same? Are both units AC ductwork set up the same?

[Troy965]

Yes RV is all off white color . Both AC's are working and run on high I believe they run through the same ductwork

[chuckster57]

Is your relatives AC ducted the same?
Do you have the “whisper quiet” with the returns on the sides of the ceiling?

[Troy965]

Yes all the same. Only difference is the Sandpiper has 4 ducts in the front living area and my alpine only has 2 . On a hot day my thermostat will read 80 /84 degrees even though I have it cranked down to 68 on high setting

[wiredgeorge]

Troy, gets warm down here in South Texas as well. First thing you need to consider is why your camper is too warm.

Have you taken metal hvac tape and sealed inside all the outlets and made sure that the seal between intake and exhaust part of the lower unit are all sealed well?

Next, your windows get smoking hot from the sun. I put very very dark tint on mine but others have put stuff over the outside to block the sun. I would be careful putting stuff over the inside especially if it is reflective as it might cause the windows to heat and get damaged. Parking in shade helps, if possible.

Try not to open the door and leave it open often. Clean the coils on your A/C units. Not sure what kind of ducting you have but on my camper, the end outlets were just open to the void under the roof. I stuffed pool noodles there so cold air isn't going into the void between roof and ceiling.

I also bought an RV Airflow gizmo I put in my lower unit. A lot of folks say it is just a piece of styrafoam but it really works, especially if you don't use the "quick cool" feature which shouldn't needed if you full time. It causes a lot more volume of air coming out of the outlets.

Your RV is poorly insulated and the ductwork was poorly installed and these things help. I have ONE 15K BTU Dometic A/C in my 28" Cougar and also use a portable A/C I vent out the window and the temps stay in the mid-70s in triple digit sun. Oh yeah, I use a good fan to distribute the air.

[Troy965]

I would like to seal the return under the ac unit but with the duct work I'm not sure how to do it . There is no access directly underneath both units I'd have to get on roof to see how the units could be lifted up .

[chuckster57]

Originally Posted by Troy965

I would like to seal the return under the ac unit but with the duct work I'm not sure how to do it . There is no access directly underneath both units I'd have to get on roof to see how the units could be lifted up .

The unit is screwed down to the roof from the top. Your better off inspecting as much ductwork as you can by removing interior vents/grills.

[Troy965]

Thanks for the info Chuck

[ChuckS]

The newer Alpines.. and I mean everyone built since 2020 all have terrible duct work underneath the roof AC units.

You must remove the four lag bolts and lift the AC up and sit it aside to see what you will see in this video of a 2021 Alpine..

You can do this yourself and fix the low airflow and lousy cooling you are experiencing

Watch this video filmed on an Alpine, what your problem is and what you can easily do yourself to correct the issue and be much much happier..

Until you do this you WILL NEVER have good cooling from those two roof units … period

https://youtu.be/-QJTxSDZRWE

[Alpine]

For a bit of help cooling your RV...

Go to a Big box store pick up Magnetic Floor Vent Covers. No sense filling your floor duct tracks with cold air. Keep it in the living space.

Make (foam-board) covers for your cold air return vents ( I have two grates intigrated in the stairs). No sense filling your basement area with cold air! Keep it in the living space.

Give it a go!

[Roper46]

Originally Posted by Alpine

For a bit of help cooling your RV...

Go to a Big box store pick up Magnetic Floor Vent Covers. No sense filling your floor duct tracks with cold air. Keep it in the living space.

Make (foam-board) covers for your cold air return vents ( I have two grates intigrated in the stairs). No sense filling your basement area with cold air! Keep it in the living space.

Give it a go!

Very good idea ! Never even thought about all the cool air loss in those places. Thanks.

[flybouy]

Originally Posted by Alpine

For a bit of help cooling your RV...

Go to a Big box store pick up Magnetic Floor Vent Covers. No sense filling your floor duct tracks with cold air. Keep it in the living space.

Make (foam-board) covers for your cold air return vents ( I have two grates intigrated in the stairs). No sense filling your basement area with cold air! Keep it in the living space.

Give it a go!

We have a travel trailer so no return grill to the pass thru. The floor registers get covered with rugs. A floor runner for the vinyl floor and "carpet samples" (those small bound pieces of carpet) go over the registers in the carpeted areas.

[Roper46]

I might also look into replacing the floor registers with the closeable type. I think I read this either in this thread or another ref the same issue.

So reference the return area under my steps, do you just cut some styrofoam to fit behind the step?

[Alpine]

Originally Posted by Roper46

I might also look into replacing the floor registers with the closeable type. I think I read this either in this thread or another ref the same issue.

So reference the return area under my steps, do you just cut some styrofoam to fit behind the step?

I just custom cut to fit tight in front of the grill! And to clear up confusion... the foam board I use is the stuff you get at the "Dollar-25 store" or Walmart, that is very thin. Not the 1" or 2" heavy boards.

[Roper46]

Originally Posted by Alpine

I just custom cut to fit tight in front of the grill! And to clear up confusion... the foam board I use is the stuff you get at the "Dollar-25 store" or Walmart, that is very thin. Not the 1" or 2" heavy boards.

Thanks for the update.

[travelin texans]

Just be sure to remove all those vent covers & open areas to the storage areas you've blocked, they are the return air for your furnace & help heat the storage areas as well.

[ChuckS]

If you take the time to watch the FIRST video I put up this will correct about 95% of your poor cooling issues on that Alpine.. Until you remove those roof AC units and correct whats wrong underneath you will NEVER have sufficient cold air flow...

Four bolts, no wires to disconnect.. lay a blanket on the roof and pull the four lag bolts out and lift the AC and sit on the blanket ( to prevent TPO damage ).

Use a roll or two of aluminum HVAC tape from walmart, etc and clean up the blocked passages and mess you find and properly tape and seal the duct work.

Reinstall AC making sure the original gasket seal is good

You CANNOT DO ANY of this work from inside the Alpine...

Blocking off the floor heater registers will help and blocking off the stairwell Furnace returns is HUGE...

The returns are a joke and do nothing for furnace return air.. They "Might" help exchange air but the furnace ... if mounted underneath like my Alpine is draws 99% of its air from under the belly

This video shows you clearly what those furnace return ducts don't do.. We just came back from a 16 day trip. The furnace was operated every morning and evening and the stairwell returns stayed BLOCKED

IN nine years of use I have never had a furnace over temp issue nor have we had any operating issues...

The basement area has its own dedicated heat duct and the under belly has two ducts laying in the belly to heat up the tanks, etc..

Video of furnace return ducts and what they don't do in my 2014 Alpine...

https://youtu.be/lfY5-egoLz0