Official statement from Scott Hubble concerning the Air8 air conditioner

AirBoss

@Sharon_is_SAM
Thanks much! Good info and good look at the structure. As with any manufacturing operation while there is room for improvements in materials and process, those must be weighed against impacts to production, viability, and most importantly, cost. 

I don't know much about how other RV's are constructed but I've spent enough time in everything from a tent-trailer to 36' Class A's to know nuCamp does a very nice job of controlling costs while offering a well made rig using quality materials.

Full stop...

Sharon_is_SAM

Ok, this is from Creed at the factory:  aluminum outside, Reflectix next, then aluminum struts with styrofoam insulation, then plywood inside. No Azdel in roof.

Denny16

Thanks, that is nice to know info.  They Ply and foam are the installation, interesting while reading the preceding discussion, I was thinking Reflectix on the inside of the roof might help, then learned nuCamp has done just that, Cool...

I wonder if adding a second layer of Reflectix on the inside between the foam and inside plywood panel might add some extra benefit, at least in winter it would reflect heat back down in the cabin, not sure if it would help cool in the winter.  😎
cheers

TNOutback

This recent discussion is getting off-track from the OP, but having said that, . . .  I wonder if they use plywood in the ceiling because it can flex along the curvature of the roof and Azdel is too rigid to use there?  I understand Azdel is more expensive, and at least for me, is a huge selling point.  Still wondering why ply?  (Rhyme intended

simonseyz

My late model 2018 400 does not have foam insulation in the ceiling. It's a white fiber type of insulation.

Denny16

Ply may give a better underlayment for the headliner material that is covering it?
cheers

Sharon_is_SAM

Found this regarding the insulation:

How are your trailers insulated 

Created by: Michael Skidmore 

Modified on: Thu, 24 Oct, 2019 at 8:47 AM

---

How are your trailers insulated

For the Tab/Tag/Cirrus- The R-value of the cut insulation we place between the rafters is rated as a 3.6. We use a foiled double bubble, which lays on top. Unlike traditional insulation this product is not rated by an R-value. Bubble insulation is rated by it's reflectivity and emissivity. R-values are based on thermal resistance (how long heat takes to pass through the product), the thicker it is the higher the R-value. Bubble insulation is very thin, 1/8", but has a high reflectivity, 96%, and a low emissivity, 4%. Only 4% of radiant heat passes through the insulation, we are not trying to slow the way heat passes through the insulation but trying to slow the way heat passes through the insulation but trying to eliminate heat from passing through it. The R-value of the Azdel and block insulation combination is rated as a 4.5.

AirBoss

@Sharon_is_SAM
As always...a fountain of information. Thank you. 

TabberJohn

Sharon_is_SAM said:

Found this regarding the insulation:

How are your trailers insulated 

Created by: Michael Skidmore 

Modified on: Thu, 24 Oct, 2019 at 8:47 AM

---

How are your trailers insulated

For the Tab/Tag/Cirrus- The R-value of the cut insulation we place between the rafters is rated as a 3.6. We use a foiled double bubble, which lays on top. Unlike traditional insulation this product is not rated by an R-value. Bubble insulation is rated by it's reflectivity and emissivity. R-values are based on thermal resistance (how long heat takes to pass through the product), the thicker it is the higher the R-value. Bubble insulation is very thin, 1/8", but has a high reflectivity, 96%, and a low emissivity, 4%. Only 4% of radiant heat passes through the insulation, we are not trying to slow the way heat passes through the insulation but trying to slow the way heat passes through the insulation but trying to eliminate heat from passing through it. The R-value of the Azdel and block insulation combination is rated as a 4.5.

Great info!
I guess that is a typo in there. I crossed through it -- I think.
It would be nice to know the different construction/insulation specs for each section since it appears they differ to various degrees.  
Floor: X + X + X = R-value of Y
Walls: X + X + X = R-value of Y
Roof: X + X + X = R-value of Y

Based on the CS and S shell photo posted I gather there is more heat gain/loss through the aluminum struts since the foam insulation is only between the struts, right?

Tampakayaker

Based on previous posts it seems like people have had good luck reducing interior temps on all models by using an EZ Up type canopy over their camper, especially the lighter colored or reflective ones. Maybe Nu Camp needs to include something similar to this with every purchase?    

Sharon_is_SAM

https://youtu.be/YvzuQUGto-g 

Go to 4:20 to see the Reflectix/bubble insulation use on the roof during construction.

RFraer

A couple of weeks ago I was contacted by Elwell.  They offered to install the upgraded Elwell AIR8 AC that we have been hearing about. I live in the Charleston SC area and they wanted to see how the new Air8 performs in a high humidity enviroment. The technician from Elwell indicated that the new unit had approximately 20% increase in performance.  The new unit was installed yesterday at my residence. The install took approximately 3 hours. The team from elbow were very courteous and professional. The new unit has the same footprint and to me it looks identical to the older unit, The install team also relocated the temperature sensor. Unfortunately, my 400 with the three way fridge does not have a convenient location for the new sensor. The technician ultimately Located the sensor at the right side of the Radio. The location may need to be changed because the radio itself puts out a significant amount of heat which may affect the reading of the thermostat, depending if the radio is on or off. The technician did show me how to reroute the wiring if relocation is necessary.  This morning at I connected the 400 to a 20 amp 110v outlet. The outside temperature at 9 am was 80F and 91% Humidity.  During the install the technician told me he cut the 3 vent hoses so they were as short as possible, this was done to reduce noise and increase cooling efficiency. I did notice a decrease in the noise level not only on the interior but also the exterior.  I set the thermostat to 73F so the compressor has not cycled and has been running constantly since 9am.  Today in Charleston we have had overcast skies in the morning and partly sunny in the afternoon. The camper is pointed north and is on a cement driveway with no shade. The radio is off, refrigerator off, fans off, a USB portable fan is on and pointed at the roof to circulate air (this was suggested by Elwell).  Below are some or the temperature measurements I took. I did close the shade on the rear widow at noon because of the sun heating the bed area, this is something I would have done if I were camping.

 Though it may not be apparent by the temperature measurements I took I did feel an improvement with the new unit. I felt very comfortable until noon. It was a bit warn from noon till 3pm but I never started to sweat as I would have with the older unit. A front came through with rain at 3pm and cooled things down. In my unprofessional preliminary opinion this new AIR8 makes the camper feel about 5 degrees cooler. I will be taking the 400 to a local state campground next week were I have been before in high temperatures, this will give me a better opportunity to assess the performance and I will give an update when I return. I appreciate NuCamp and Elwell’s effort in resolving this issue.

ChrisFix

While it is admirable what NuCamp and Elwell are doing to try and rectify the inadequate T@B 400 cooling situation...I can not be happier to have a Dometic Cool Cat. In central NC, 95 degrees, 80%+ humidity and full sun, it is no problem having a 72 degree interior. I believe all of this is largely a matter of sheer BTUs - end of story. 
Hopefully the new Air8+ and the installation mods will make it a liveable solution, but I'd be surprised if NuCamp goes back to the Air8 for the T@B 400 anytime soon.

Dutch061

ChrisFix said:

While it is admirable what NuCamp and Elwell are doing to try and rectify the inadequate T@B 400 cooling situation...I can not be happier to have a Dometic Cool Cat. In central NC, 95 degrees, 80%+ humidity and full sun, it is no problem having a 72 degree interior. I believe all of this is largely a matter of sheer BTUs - end of story. 
Hopefully the new Air8+ and the installation mods will make it a liveable solution, but I'd be surprised if NuCamp goes back to the Air8 for the T@B 400 anytime soon.

Chris,

You are 100% correct on the issue being BTU's, I have tried everything possible on our 2020 400 BDL and the bottom line is that the original Air8 air conditioner just doesn't have enough BTU's. We typically don't camp much in the heat of the summer but went this weekend and only to about 1600 Ft elevation. Overnight temperatures were in the mid to upper 60's so I could get by at night without AC.

However, this morning I fired up the generator and the air conditioning while it was still cool outside. At 9:00 AM it was 72 outside, Air set at 72 inside and the temperature was 76 according to the AC Control  (sure wish I would have looked at the Alde)  and it was losing the battle already. I was in full sun and the thermal load is just to much for a 6K (+/-) unit to contend with. I am hopeful that the additional 2K (+/-) BTU will push it over the hump, time will tell the rest of the story. I have some private chats going with a couple of others who have the Beta Test Unit and I am looking forward to their results.

All of this said, even if we do camp in the heat of the summer, we are typically not in the camper during the heat of the day anyway but it still needs to be capable of maintaining a livable temperature!

Brad

Denny16

Brad, make sure you get your name on the Air8 replacement list.
cheers

Dutch061

Denny16 said:

Brad, make sure you get your name on the Air8 replacement list.
cheers

Added weeks ago, but thanks for the reminder!

Brad

AirBoss

I am one of those who had the Air 8 Plus installed but unfortunately I've not been able to run any significant tests to speak of and won't be able to until 22-29Aug trip with temps in low 90's. 

Fingers crossed there is a noticeable improvement. 

johnfconway

At 67 I hope the T@B 400 is with us for all remaining RVing years. There is a potential valuation issue. Like many we are at high elevation (6100 ft.) and low humidity with reliable night cooling. We tend to camp at higher elevations. The upgrade will be a plus, but not something that keeps us from going anywhere. When the time comes to sell, be it us or through estate, I hope no one takes a hit because it's a 2020.

RFraer

I was able to tryout the upgraded AIR8 again today. This time i let the camper heat soak in the sun on my driveway. I took some temperature measurements starting at noon this time. The AIR8 had almost no effect. The interior cabin temperature started at 100F, after running  the AIR8 for  1 1/2 hours the cabin temperature dropped to 94F. The outside temperature was 94F, I could have stayed outside and then Just as cool. Clouds came in around 2 pm and the temperature dropped to 89F. The cabin temperature reached to 82F after 3 hours. This is not no different than what I experienced with the original AIR8. 

Dutch061

RFraer said:

I was able to tryout the upgraded AIR8 again today. This time i let the camper heat soak in the sun on my driveway. I took some temperature measurements starting at noon this time. The AIR8 had almost no effect. The interior cabin temperature started at 100F, after running  the AIR8 for  1 1/2 hours the cabin temperature dropped to 94F. The outside temperature was 94F, I could have stayed outside and then Just as cool. Clouds came in around 2 pm and the temperature dropped to 89F. The cabin temperature reached to 82F after 3 hours. This is not no different than what I experienced with the original AIR8. 

I am sorry to hear this update.

Brad

AirBoss

Indeed. Most unfortunate if that's what we can expect. I was hopeful that the addtional 20-25% BTU would offer a more impressive result. 

While I understand it is likely difficult for a unit of the size of Air 8 Plus to recover from a heat soak and staring temps of over 100, fact is if one is on the road for 6-7 hours in higher temps that pretty much what you can expect to start with when you arrive at the CG. 

It's one thing to maintain a range of 72-78 degrees all day if you start at an ambient temperature that's within 5-7 degrees of that. Most any A/C unit worth it's salt can manage that. Given that the Air 8 operates on 100% recirculated air and the vent temps when running on high seem to hover in the mid to upper 60's range, it's a bit baffling that after runing for 4 hours it cannot overcome those temps to a much greater degree. 

One question I have is if it was possible to reengineer the unit to produce 20% more BTU's, what's the barrier to reengineering it produce 50% more? Is the delta in BTU's between Air 8 and Cool Cat the only factor in the difference in performance under similar circumstances? I'm no HVAC guy and the question may be simplistic, but one I'm curious about nonetheless. 

 

rh5555

I have a question on how our wonderful contributors are measuring the cabin temperature in their tests.  When using the AIR8, I have noticed it takes forever to cool down the hot walls, cabinets, table and other massive items when starting with a hot trailer, but the air temperature feels quite comfortable long before those surfaces cool down.  It feels acceptable long before the ALDE temperature sensor says it should be.  I fully agree that a more powerful unit would cool those hot surfaces faster, but if the cabin temperature feels OK, isn't that good enough?

1968Healey

Thankfully we use out 2020 T@B 400 in the PNW where AC isn’t a hard requirement like it can be in the southern part of the US - however when we need it, we need it.

Watching the developments here is concerning as we do plan on taking our T@B to AZ for some extended stays with family.  We’ll need the AC then.  

I do want to point out one very annoying part of this whole AC saga.

We pre-ordered our 2020 T@B 400 in ~March of 2019.  We knew about the different floor material and wanted that.  2020 models weren’t out yet, so contacted nuCamp directly for a full list of all changes.

We were assured that the 2019 -> 2020 changes were a short list; the sink, the new p-trap on the kitchen sink and a few other things.  The factory made no mention of a new AC unit, which is a pretty substantial change.

Now, if they told us about this new AC change I wouldn’t have objected.  Being in the PNW I’m not a BTU to size expert and wouldn’t have picked up on this potential problem.  However, it’s still unsettling that the factory didn’t know or wasn’t communicating such a large change only 2 months out to production.

AirBoss

rh5555 said:

I have a question on how our wonderful contributors are measuring the cabin temperature in their tests.  When using the AIR8, I have noticed it takes forever to cool down the hot walls, cabinets, table and other massive items when starting with a hot trailer, but the air temperature feels quite comfortable long before those surfaces cool down.  It feels acceptable long before the ALDE temperature sensor says it should be.  I fully agree that a more powerful unit would cool those hot surfaces faster, but if the cabin temperature feels OK, isn't that good enough?

In theory, yes. If it "feels" more comfortable then that's a good thing. Yes, 76 feels better than 82. But so does 88 feel better than 94. It's a relative thing and to some degree the actual numerical figure is a gauge on performance, not necessarily comfort. I don't have an infrared sensor. I was using an ambient thermometer and...wait for it...a Brookstone meat thermometer, which I trust completely with my filet mignon! But for the record, the Brookstone is within 1-1.5 degrees of live NWS and AccuWeather temps so it's within a reasonable margin of error for my purposes. 

Anyway, yes. To your point I'm not living on or in my cabinets or ceiling. Having said that, I don't believe it's asking too much to expect an a/c unit to perform at an acceptable level. And by acceptable I'd say given the relatively small cubic footage of the 400, one might expect a more robust reduction in ambient temps over a period of 5-7 runtime. 

Looking at @RFraer S/S from yesterday he started the unit at an outside temp of 80 and interior (ambient I presume) at 75. Totally comfortable. Over the span of 6 hours runtime the outside air temp rose 15 degrees. The interior not only did not maintain 75 degrees it lost ground by 5 degrees. That's the issue...even staring from a relatively cool point. And as I mentioned above, those trends don't bode well if you're on the road for 6 hours in higher temps and set up in your CG at say 300pm. It would seem based on these samples that one cannot expect the rig to cool down significantly much before lights out. 

It also indicates the unit will incur much higher "Hobbs" meter hours if it has to run pretty much consistently day in and day out trying to maintain "comfortable" temps. Is it a show stopper, no. Is it worth looking to another rig, no. But it does reflect a situation that at least to this point, assuming all the feedback we're seeing to date are accurate, is cause for some concern.     

Dutch061

AirBoss said:

One question I have is if it was possible to reengineer the unit to produce 20% more BTU's, what's the barrier to reengineering it produce 50% more? Is the delta in BTU's between Air 8 and Cool Cat the only factor in the difference in performance under similar circumstances? I'm no HVAC guy and the question may be simplistic, but one I'm curious about nonetheless. 

 rh5555 said:

I fully agree that a more powerful unit would cool those hot surfaces faster, but if the cabin temperature feels OK, isn't that good enough?

@Air@AirBoss

I think the issue is size, meaning that there is a limited amount of space for the Air8 to fit into and it is probably a major rebuild to either redesign that space or to move to the left front (IE Cool Cat). Short of a miracle refrigerant that has more efficient properties I don't now of a way to get more BTU from a smaller unit. Going back to the days of my 5th wheel that had Coleman Polar Mach Units, if I remember correctly the 13.5K BTU unit could deliver a delta temperature of 15 to 17 degrees and a 15K BTU unit would deliver 19 to 21 degrees delta. With the original 13.5K if it was hot and humid, it was 85 or hotter inside. I ended up with 2 x 13.5K BTU for a 36 foot fifth wheel and it was still marginal (Low to mid70's) on a really hot and humid day in SC.

@rh5555

In my experience this morning, I started with a fairly cool cabin temperature (probably 74ish) and definitely a cool enough outside temperature that it should have not had an issue controlling the inside temperature. But the simple fact is that it can't. I was in full sun, the door side, roof, and front, (the street side was in the shade) and with an outside temperature of 72 there should not be an issue with holding temperature. I was at 76 and climbing inside and the outside temperature was still 75 or less when I shut it off to head for home. Unfortunately, this isn't what I would call "feels OK" either. I don't expect ice cubes, but I expect it to work better than this and better than what we have seen people post for results AFTER the larger unit was installed.

Brad

gulfarea

After owing 4 rv's I have found that the best A/C units are the roof mounted OR the split systems full timers put in their trailers. Art

AirBoss

Agreed. But there are alternatives given the cubic foot dynamics. Seems perhaps those were not fully vetted. 

Tampakayaker

AirBoss said:

Indeed. Most unfortunate if that's what we can expect. I was hopeful that the addtional 20-25% BTU would offer a more impressive result. 

While I understand it is likely difficult for a unit of the size of Air 8 Plus to recover from a heat soak and staring temps of over 100, fact is if one is on the road for 6-7 hours in higher temps that pretty much what you can expect to start with when you arrive at the CG. 

It's one thing to maintain a range of 72-78 degrees all day if you start at an ambient temperature that's within 5-7 degrees of that. Most any A/C unit worth it's salt can manage that. Given that the Air 8 operates on 100% recirculated air and the vent temps when running on high seem to hover in the mid to upper 60's range, it's a bit baffling that after runing for 4 hours it cannot overcome those temps to a much greater degree. 

One question I have is if it was possible to reengineer the unit to produce 20% more BTU's, what's the barrier to reengineering it produce 50% more? Is the delta in BTU's between Air 8 and Cool Cat the only factor in the difference in performance under similar circumstances? I'm no HVAC guy and the question may be simplistic, but one I'm curious about nonetheless. 

 

We don't have a 400, so this isn't based on any experiences like you all are having.

But since T@Bs are closed systems similar to cars, would it help to open the windows or turn on the overhead fans to get the hot air out while the AC is blowing out the cool air?

I know most of the auto manufacturers recommend turning on the fan speed higher and open windows slightly at the rear of the vehicle to help force the hot air out and the temps to drop quicker.

I know that helps with my dark blue truck that's been sitting in the FL sun all day long.

AirBoss

@Tampakayaker
Seems there's two schools of thought on this. Yes, I've heard that philosophy as well. I've been "exhausting" the warm air throught the roof fan first, before firing up the A/C and leaving the roof vent open (fan off) a bit for the fist little while. And on a few ocassions when I had the original Air 8 did just as you indicated. 

When the Elwell folks installed the Air 8 Plus they said it's best to seal it up after exhausting the warmer air. Windows closed, vents closed. Run a small fan pointed toward the ceiling to move the warmer air down to mix with cooler air. 

I'll give both a try in a month when we're staying in CA wine country for a week in low 90 temps. That'll be the first real opportunity for me to test the new unit. 

I'll post results when I can. It's a first world problem to be sure. Hopefully the my results will be a bit more "comfortable" than what I've seen from the few other folks here who had the Plus unit installed...time will tell. 

RFraer

0n Monday and Tuesday of this week I took my 2020 TAB 400  with the AIR8+ on a fishing trip To Santee State Park here in South Carolina. I camped in a site that had 40-60% shade. The sky was partly sunny most of the day.  I took temperature readings when I was at the camper.  When I arrived Monday at 12:30 the camper was close to being fully heat soaked. The AC compressor ran all day and finally turned off around 7:15 PM.  The AIR8 thermostat was set to 83F but the cabin temperature was 77F when the compressor stopped. The discrepancy between the thermostat and the actual temperature I believe is due to the placement of the temperature sensor near the roof.  My sensor was placed above the 3-way refrigerator on the right side of the radio. The Aldi was showing 78F cabin temperature.  On Monday the AIR8+ could not start to stabilize the cabin temperature until 6:30 PM. On Tuesday, the hotter day the AIR8+ started to lose the battle at around 3:00 pm and regained it at around 7:00pm.