Crusader Inadequate AC or poor insulation

nailzscott · 08-25-2018, 05:33 PM

I just did some testing on the coach - since it won't get below 78 inside when it's 90 outside. I used a laser pointing thermal temperature gauge to point toward various places around the coach. Since it was only a 76 degree day outside, I did not expect to see much of a problem. What I found was that the coach's inside wall of the sun facing side had temperatures of around 104 degrees. Inside of a cabinet on that side's slide, the inside surface temperature was 118 degrees. This Crusader 297 RSK is supposed to have the "Extreme Thermal Package.

If it ever gets back to 90 degrees and sunny, I'm going to do the test again - but it's no wonder the AC doesn't get it cool on hot days.

Anyone else ever done any wall temperature testing?

Thanks

rracer5 · 08-25-2018, 07:23 PM

Quote:

Originally Posted by nailzscott

I just did some testing on the coach - since it won't get below 78 inside when it's 90 outside. I used a laser pointing thermal temperature gauge to point toward various places around the coach. Since it was only a 76 degree day outside, I did not expect to see much of a problem. What I found was that the coach's inside wall of the sun facing side had temperatures of around 104 degrees. Inside of a cabinet on that side's slide, the inside surface temperature was 118 degrees. This Crusader 297 RSK is supposed to have the "Extreme Thermal Package.

If it ever gets back to 90 degrees and sunny, I'm going to do the test again - but it's no wonder the AC doesn't get it cool on hot days.

Anyone else ever done any wall temperature testing?

Thanks

What was the temp. of the air coming out of the A/C ducts?

nailzscott · 08-25-2018, 07:46 PM

The air from the vent was plenty cold - I believe it was around 59

valleyduo · 08-25-2018, 08:08 PM

I'd like to do a similar test on our ceilings some time. Had to perform a minor surgery on the roof recently due to a spotter that was spotting girls instead of tree limbs I was near. Ended up with a minor structural repair when we got home. From just the small area I worked there were a lot of uninsulated voids along the roofline. Our ac actually works pretty well so I was a little surprised how poorly insulated it was.

rracer5 · 08-25-2018, 08:08 PM

Quote:

Originally Posted by nailzscott

The air from the vent was plenty cold - I believe it was around 59

If you haven't tried already, I've found that I have to chase the sun by closing the shades anyplace the sun shines in. The heat through the windows is hotter than the walls.

nailzscott · 08-26-2018, 05:40 AM

Yes, closing the shades was the first step. I’d hate to see how bad it would be if they were open.

nailzscott · 08-26-2018, 05:48 AM

Valleyduo,

The ceiling on mine did not have the same problem as the walls.

According to Primetime, the coach should have R52 insulation value. I have trouble believing that.

Team Poopy · 08-26-2018, 08:59 AM

Are you getting good sirflow from all the vents? Originally I could hang meat in the back of our trailer where the unit is and it would be 80 in the front bedroom. Followed an old post here and sealed all the vents internally to the duct work and it cured our issues. Blew sawdust and other debris from forward vents once we had good air flow.

wshelton1 · 08-26-2018, 12:59 PM

The fix that works for sure is to add AC ON THE BEDROOM VENT. It was prewired on mine. It cost me $600 installed. I assume you have 50 Amp Service.

ben31 · 08-26-2018, 01:14 PM

First step. Put the fan on high from the time you get up, until the sun goes down. Don't let the AC decide for you. It will never keep up.
Second, do you have the bedroom AC? If so, leave it on auto and keep the blinds in there closed. If not, you might want to think about getting it. Those 5ers are way too big to rely on a single AC.
Third, get slide toppers. They keep the sun off of the top of the slides. That helps a great deal.

We also put one of those vent insulation pillows in the LR roof vent. It helped a lot. I don't remember if your model has that vent, or not.

Tiggerdad · 08-26-2018, 02:21 PM

You will never get R54 insulation in any rv. Walls,ceilings, side, slideouts and bottom are not deep enough. R11 on the sides is also a joke because it requires 3 1/2 inches of fiberglass for r-11. Never seen much insulation in the underbelly but it is difficult to keep dry because of road spray. 4" of foam on the bottom would only give you R-4 All of the manufacturers use questionable R factors. Look at your wall thicknesses at your entrance door to determine your wall thickness.

I believe your AC is functioning properly. We have almost the same size rig but need 2 AC's to maintain upper 70's low 80's during 100-104 degree days in Austin and San Antonio. Best way to cool after adding a second AC is to turn that AC down as low as possible at night to help with the heat buildup coming and the outside temps come up. The use blankets at night.

rracer5 · 08-26-2018, 03:37 PM

Quote:

Originally Posted by Team Poopy

Are you getting good sirflow from all the vents? Originally I could hang meat in the back of our trailer where the unit is and it would be 80 in the front bedroom. Followed an old post here and sealed all the vents internally to the duct work and it cured our issues. Blew sawdust and other debris from forward vents once we had good air flow.

Quote:

Originally Posted by wshelton1

The fix that works for sure is to add AC ON THE BEDROOM VENT. It was prewired on mine. It cost me $600 installed. I assume you have 50 Amp Service.

X2 These 2 post were going to be my next suggestions. Sealing the vent outlets to the internal duct work & making sure there are no blockages or duct collapses would go a long way.

FORKLIFMAN · 08-26-2018, 03:43 PM

If you follow what Ben said, you will have the same problem I have, when its 110 degrees outside. DW complains it's too cold inside here!

Casey r · 08-26-2018, 05:56 PM

Quote:

Originally Posted by rracer5

X2 These 2 post were going to be my next suggestions. Sealing the vent outlets to the internal duct work & making sure there are no blockages or duct collapses would go a long way.

Primetime 29RS did all the above plus taped up the baffle between the air return and the cold air discharge. Also blocked duct work just past last roof register to keep cold air from cooling the front end cap and rear wall. Ended up adding second A/C to make it comfortable.

nailzscott · 08-26-2018, 10:01 PM

Team Poopy, This is a 15K AC. Frankly, the airflow from all vents seems similar; but this is a Dometic Quiet Cool. They are more quiet, but I'm wondering if they have as much air flow as the old style.

wshelton1, I spent a fortune on this rig and yes, I could buy the 2nd AC (since it is wired and has the 50 amp service), but I shouldn't have to. I think it would cool fine if so much heat wasn't coming through the walls. Or if the current AC would push more air through it.

ben31, I do what you said, fan on high, all blinds down, and start super cooling it first thing in the morning (against the wife's wishes). My last 5er was a foot shorter and 10 years older, but it stayed cooler - even with 1 AC. I thought about those roof vent pillows (I have 3 vents) but it's starting to look like a dungeon in there - not really what I'm wanting. I was questioning the R54, but Primetime shouldn't say they have it - if they can't back it up. Regarding the Slide toppers, I haven't checked the temps on the slide roofs, but I will.

rracer5 & Casey r: I'll check out the vent outlets, but the air flow seems similar in all 5 vents - and temperatures similar too.

The coach is supposed to go back to the dealer so for a whole list of issues; but they are currently not sure what they are going to do on the AC. They were quite surprised by the wall temperature readings I was getting. The AC works fine on half cloudy days and when parking mostly where the sun is blocked by trees. It's just that sun on the side wall that the AC can't overcome.

Thanks for the suggestions and help.

esmoglo · 08-26-2018, 10:01 PM

We camped in TX this summer during June & July and it was hot as hot can be outside temps were very high. Our Crusader has two AC’s main unit is ducted 2nd unit in the bedroom is not

(will not buy another RV like this).

What we did to keep it 78 inside when it was 104 out, run two small fans, use reflectix on the windows, and Camco vent insulators on all three vents. Now at night, the RV was super cold but in the daytime when it was 104 out no better than 78, and that’s pretty good all things considering.

We have also camped with the Crusader at 32 degrees out and kept the camper warm with the electric fireplace & a small ceramic space heater.

heavynlori · 08-27-2018, 06:33 AM

The vent pillows work wonders for blocking heat but yes, it does darken the inside

Darker means cooler [emoji1303]

tomkatb · 08-27-2018, 07:22 AM

If the air coming out of the register closest to the ac unit is near 20 degrees cooler than the air in the rv you have a good ac unit. Well installed likely.

Therefor you do not have a big enough ac unit. Or the rv needs more insulation.

I remember when I began researching for our fiver purchase on utube video of recommendations is that if available, always take the second unit. Salesmen are not good advisers. A properly installed home unit should struggle and perhaps not be cool enough in record setting temperatures! Too big of a single unit in a house causes humidity issues. Less efficient as well. Test your house temps.

On a 95 degree day in the middle of an open area a single ac unit will not cool an Rv over 30’ long for the most part.

Exactly our case. Our unit is well insulated. Seldom does our second unit run. But, in Kansas on a 100 degree day in the middle of a big treeless rv park our two ac units struggled several hours to reach 76 degrees. About 3 hours it was pretty warm in the rv. In central Missouri on a 95 degree day we had a 100% shaded site with 30 amp service. A single unit was enough. Barely.

Get a second unit or stay north of the Mason Dixon line.

nailzscott · 08-27-2018, 08:55 AM

We have the largest AC unit available for our rig - 15K, so that leaves wall insulation, based upon my wall temperature readings.

I agree that the AC generally doing what it should - output 20 degrees less than input.

I have not tried reflectix on the windows, nor the camco vent insulator pillows.

What about the Air Vent Covers on the roof. Seems that those would help to minimize sun affects coming in there. Would black be best - to absorb the heat before it gets in - or white to reflect the sun's rays.

tomkatb - we live and camp mostly in NW Ohio and Indiana - so if all else fails, while under warranty, we may push the dealer to help on the expense of a second AC. I know - it's dreaming, but I'm tired of seeing them and they are definitely tired of me on this inadequate AC issue. They do acknowledge that they do not understand why the wall temps would be so high; so we'll see where that leads.

JohnD10 · 08-27-2018, 09:09 AM

Quote:

Originally Posted by nailzscott

What about the Air Vent Covers on the roof. Seems that those would help to minimize sun affects coming in there. Would black be best - to absorb the heat before it gets in - or white to reflect the sun's rays.

Get the white ones...

I put black MaxxAir vent covers on all three of the vents on my 5'ver for looks (matched the roof AC), and have switched the bathroom one to white as I wanted more light to add to the skylight in the shower.

The black ones hold in so much heat they really were a waste of money...except for looks, of course!

I have a Fantastic fan that will soon be mounted in the bathroom and will replace the other two black covers with white ones.

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