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bsheet2

77095

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Posted: 08/16/19 08:12am Link  |  Quote  |  Print  |  Notify Moderator

Groover wrote:

I had the same struggle recently with my Thor Palazzo about the same size. My AC's are ducted and I used an infrared thermometer to measure the temps inside the ductwork. I was actually getting 25 to 30 degree temperature drop so I came to the same conclusion as you, the unit just isn't very well sealed/insulated. At least with ducted AC's I could have both units working on the kitchen/living areas and managed to keep them comfortable. I don't know what type of stove that your camper has but mine is a little bit older unit and came with a gas stove. In expectation of heat being an issue I bought a 2 burner induction cooktop for the trip and believe that cooking on it instead of the gas cooktop helped a lot. The cooktop was $180 and I found a surprisingly good set of induction cookware for another $80 so altogether $260. It really did reduce the amount of heat put into the coach and is much easier to clean up.

About the only other easy things would be to make sure that you have double layer covers on your Fantastic roof fans and to pull in a slide during the day if that doesn't cause too much discomfort.

One final thing but it would be a bit expensive. I have heard claims that the Atwood AC's have more real capacity than the other brands and are quieter. I can't vouch for that so take it with a grain of salt. I have been trying to figure out how to compare brands myself but haven't come up with a good way yet.


Thanks for the responses.

I have arrived at the conclusion that I need to focus on improving insulation before I take any drastic steps.

Something I did discover. There are two AC vents from the ducted vent system that are under the drop down bed when it is raised. I dropped the bed down yesterday to put sheets on it and found it there was a large volume of nice cold air coming out of those vents. Suddenly that
whole forward area started getting nice and cool. I started checking other vents and found there are two that hardly have anything coming out of them. We ran the AC for a while longer and with the drop down bunk lowered about a foot or so. The AC performed much much better. Seems a quarter of the air was not making it into the cabin.

THat unit was just installed. I wonder if they messed up the tie in to the duct system??? Anyone know how to check it??? Can I drop down the inside ceiling panel as see ??

Anyway, at least we know what to do now to keep things comfortable.

Groover

Pulaski, TN

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Posted: 08/16/19 08:41am Link  |  Quote  |  Print  |  Notify Moderator

bsheet2 wrote:

Groover wrote:

I had the same struggle recently with my Thor Palazzo about the same size. My AC's are ducted and I used an infrared thermometer to measure the temps inside the ductwork. I was actually getting 25 to 30 degree temperature drop so I came to the same conclusion as you, the unit just isn't very well sealed/insulated. At least with ducted AC's I could have both units working on the kitchen/living areas and managed to keep them comfortable. I don't know what type of stove that your camper has but mine is a little bit older unit and came with a gas stove. In expectation of heat being an issue I bought a 2 burner induction cooktop for the trip and believe that cooking on it instead of the gas cooktop helped a lot. The cooktop was $180 and I found a surprisingly good set of induction cookware for another $80 so altogether $260. It really did reduce the amount of heat put into the coach and is much easier to clean up.

About the only other easy things would be to make sure that you have double layer covers on your Fantastic roof fans and to pull in a slide during the day if that doesn't cause too much discomfort.

One final thing but it would be a bit expensive. I have heard claims that the Atwood AC's have more real capacity than the other brands and are quieter. I can't vouch for that so take it with a grain of salt. I have been trying to figure out how to compare brands myself but haven't come up with a good way yet.


Thanks for the responses.

I have arrived at the conclusion that I need to focus on improving insulation before I take any drastic steps.

Something I did discover. There are two AC vents from the ducted vent system that are under the drop down bed when it is raised. I dropped the bed down yesterday to put sheets on it and found it there was a large volume of nice cold air coming out of those vents. Suddenly that
whole forward area started getting nice and cool. I started checking other vents and found there are two that hardly have anything coming out of them. We ran the AC for a while longer and with the drop down bunk lowered about a foot or so. The AC performed much much better. Seems a quarter of the air was not making it into the cabin.

THat unit was just installed. I wonder if they messed up the tie in to the duct system??? Anyone know how to check it??? Can I drop down the inside ceiling panel as see ??

Anyway, at least we know what to do now to keep things comfortable.


Since your coach was made by the same company that made mine they may have similar ductwork. Mine has a duct on either side of the AC units about 10" wide and 3" high running the full length of the coach. The distribution from the factory was very poor since the vents were evenly spaced with total disregard for where the heat was generated so I bought 4 more vents and the correct size hole saw and put some more in where I thought that they were needed. Much better now.

As for the comment that you have to live with the noise I bought some covers for the return that really quieted them down. Everyone agrees that it was a huge improvement. We can actually have conversations at the kitchen table now. I have Dometic AC's but I think that they have versions for Coleman AC's as well.

Wacko AC silencer

My Dometics had a big discharge grill for "concentrated quick cooling" that I was afraid that I would miss. After adding vents straight out from where the cold air enters the ductwork I don't miss that at all and it is still quiet. I was also concerned that the flow would be reduced without that large noisy vent so I bought a vane type wind speed gauge and convinced myself that when I shut the noisy vent the air simply went somewhere else with very little loss so I haven't lost any significant capacity. Shutting off air vents in the over-cooled bedroom also mostly just routs the air to the front areas. The Wacko's are a bit pricey but they are still chump change in the total cost of owning the RV and made the family much happier.

Good luck!

Groover

Pulaski, TN

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Posted: 08/16/19 08:51am Link  |  Quote  |  Print  |  Notify Moderator

dougrainer wrote:

Groover wrote:

I had the same struggle recently with my Thor Palazzo about the same size. My AC's are ducted and I used an infrared thermometer to measure the temps inside the ductwork. I was actually getting 25 to 30 degree temperature drop so I came to the same conclusion as you, the unit just isn't very well sealed/insulated. At least with ducted AC's I could have both units working on the kitchen/living areas and managed to keep them comfortable. I don't know what type of stove that your camper has but mine is a little bit older unit and came with a gas stove. In expectation of heat being an issue I bought a 2 burner induction cooktop for the trip and believe that cooking on it instead of the gas cooktop helped a lot. The cooktop was $180 and I found a surprisingly good set of induction cookware for another $80 so altogether $260. It really did reduce the amount of heat put into the coach and is much easier to clean up.

About the only other easy things would be to make sure that you have double layer covers on your Fantastic roof fans and to pull in a slide during the day if that doesn't cause too much discomfort.

One final thing but it would be a bit expensive. I have heard claims that the Atwood AC's have more real capacity than the other brands and are quieter. I can't vouch for that so take it with a grain of salt. I have been trying to figure out how to compare brands myself but haven't come up with a good way yet.


1. You CANNOT use a IR Thermometer to performance test a AC unit--Home or RV
2. BTU's are BTU's. Regardless of Brand, they will put out the BTU's they are designed and built for. Atwood is trying to get into the RV market. I find noise complaints funny. You are putting a large AC on top your roof of your RV and then you complain about any noise???????
Ever Had a Residential house with a AC unit outside your Master Bedroom area? I HAVE. When we purchased our last 2 houses, the criteria was NO AC unit outside the Master Bedroom area. Noise is Noise. While some state Atwoods have a quieter signature, I will go with the 2 brands that have been around for almost 50 years--Dometic and Coleman. There have been a few companies that have tried to enter the RV market in the past 10 years and they quietly walked away leaving customers with no parts or support. That is why I would not advise going to any AC unit other than Dometic or Coleman. They are here and will still be here in the future. Doug



Very entertaining. Atwood is owned by Dometic and the claim of more cooling for less power with less noise is on their joint web site:

Atwood AC

As for measuring temps with an IR thermomete, I can and I did. As with all measuring devices you need to be aware of their accuracy and limitations but that was the best data I had so I used it.

oldave

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Posted: 08/16/19 09:46am Link  |  Quote  |  Print  |  Notify Moderator

I keep a couple of small fans in the RV . I us them inside and out
Sometime I need to blow the cool bedroom air up front

While I don't think you will put to large of an A/C in your RV this
reminded me of a man I worked with yrs ago .
He had an A/C in his home that was way to large for the home .
It would get really cold but they were still uncomfortable .
Finally an air cond man explained to them that the unit should be
properly matched to the area and heat load otherwise it will not
run long enough to remove the nasty Texas humidity .

That was it they were cold but clammy feeling .

On the other hand if the unit is to small you may never get cool .

dougrainer

Carrolton, Texas

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Posted: 08/16/19 10:08am Link  |  Quote  |  Print  |  Notify Moderator

Groover wrote:

dougrainer wrote:

Groover wrote:

I had the same struggle recently with my Thor Palazzo about the same size. My AC's are ducted and I used an infrared thermometer to measure the temps inside the ductwork. I was actually getting 25 to 30 degree temperature drop so I came to the same conclusion as you, the unit just isn't very well sealed/insulated. At least with ducted AC's I could have both units working on the kitchen/living areas and managed to keep them comfortable. I don't know what type of stove that your camper has but mine is a little bit older unit and came with a gas stove. In expectation of heat being an issue I bought a 2 burner induction cooktop for the trip and believe that cooking on it instead of the gas cooktop helped a lot. The cooktop was $180 and I found a surprisingly good set of induction cookware for another $80 so altogether $260. It really did reduce the amount of heat put into the coach and is much easier to clean up.

About the only other easy things would be to make sure that you have double layer covers on your Fantastic roof fans and to pull in a slide during the day if that doesn't cause too much discomfort.

One final thing but it would be a bit expensive. I have heard claims that the Atwood AC's have more real capacity than the other brands and are quieter. I can't vouch for that so take it with a grain of salt. I have been trying to figure out how to compare brands myself but haven't come up with a good way yet.


1. You CANNOT use a IR Thermometer to performance test a AC unit--Home or RV
2. BTU's are BTU's. Regardless of Brand, they will put out the BTU's they are designed and built for. Atwood is trying to get into the RV market. I find noise complaints funny. You are putting a large AC on top your roof of your RV and then you complain about any noise???????
Ever Had a Residential house with a AC unit outside your Master Bedroom area? I HAVE. When we purchased our last 2 houses, the criteria was NO AC unit outside the Master Bedroom area. Noise is Noise. While some state Atwoods have a quieter signature, I will go with the 2 brands that have been around for almost 50 years--Dometic and Coleman. There have been a few companies that have tried to enter the RV market in the past 10 years and they quietly walked away leaving customers with no parts or support. That is why I would not advise going to any AC unit other than Dometic or Coleman. They are here and will still be here in the future. Doug



Very entertaining. Atwood is owned by Dometic and the claim of more cooling for less power with less noise is on their joint web site:

Atwood AC

As for measuring temps with an IR thermomete, I can and I did. As with all measuring devices you need to be aware of their accuracy and limitations but that was the best data I had so I used it.


ANY qualified AC Technician(I am one) will tell you IR thermometers are NOT for taking air output/input temps. IR cannot sense AIR. Now, it will sense the solid objects like ductwork or louvers. Dometic purchased Atwood and if Dometic follows past procedures and purchases will probably drop the Atwood line. Of course they have to advertise perceived better features. What? Advertise, we have another 13.5 or 15k AC brand that works just like our original brand? Dometic also purchased the Atwood Refer brand also and I believe they have dropped the Atwood production and are just selling what little they have left.
It is very hard to find Atwood info on Dometic's website. Doug

time2roll

Southern California

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Posted: 08/16/19 10:10am Link  |  Quote  |  Print  |  Notify Moderator

bsheet2 wrote:

Actually the AC did better today. I started everything early in the morning and we minimized going in and out. It stayed decent in the heat of the afternoon.
I would never shut it off in TX heat. Let it cycle overnight and as the sun comes up it will run continuous all day.


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bsheet2

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Posted: 08/16/19 11:48am Link  |  Quote  |  Print  |  Notify Moderator

Groover wrote:



Since your coach was made by the same company that made mine they may have similar ductwork. Mine has a duct on either side of the AC units about 10" wide and 3" high running the full length of the coach. The distribution from the factory was very poor since the vents were evenly spaced with total disregard for where the heat was generated so I bought 4 more vents and the correct size hole saw and put some more in where I thought that they were needed. Much better now.

As for the comment that you have to live with the noise I bought some covers for the return that really quieted them down. Everyone agrees that it was a huge improvement. We can actually have conversations at the kitchen table now. I have Dometic AC's but I think that they have versions for Coleman AC's as well.

Wacko AC silencer

My Dometics had a big discharge grill for "concentrated quick cooling" that I was afraid that I would miss. After adding vents straight out from where the cold air enters the ductwork I don't miss that at all and it is still quiet. I was also concerned that the flow would be reduced without that large noisy vent so I bought a vane type wind speed gauge and convinced myself that when I shut the noisy vent the air simply went somewhere else with very little loss so I haven't lost any significant capacity. Shutting off air vents in the over-cooled bedroom also mostly just routs the air to the front areas. The Wacko's are a bit pricey but they are still chump change in the total cost of owning the RV and made the family much happier.

Good luck!



Thanks for that info. I will have to open things up and see if I can figure out the ducting. Will check out the noise dampener as well.

bsheet2

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Posted: 08/16/19 11:52am Link  |  Quote  |  Print  |  Notify Moderator

time2roll wrote:

bsheet2 wrote:

Actually the AC did better today. I started everything early in the morning and we minimized going in and out. It stayed decent in the heat of the afternoon.
I would never shut it off in TX heat. Let it cycle overnight and as the sun comes up it will run continuous all day.


Running on the genny. Don't have a 30 amp to plug in to. Prefer not to run the genny all night.

oldave

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Posted: 08/16/19 12:19pm Link  |  Quote  |  Print  |  Notify Moderator

We have run our gen day and night for as long as we needed it .
That's what its for . I'm not going to try to sleep when its
hot while all I have to do is start the gen .
Diesel is currently cheap so spend some dollars and sleep well .

Actually the Onan likes to run .
Low hours on one is not always a good thing .

bsheet2

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Posted: 08/16/19 05:02pm Link  |  Quote  |  Print  |  Notify Moderator

oldave wrote:

We have run our gen day and night for as long as we needed it .
That's what its for . I'm not going to try to sleep when its
hot while all I have to do is start the gen .
Diesel is currently cheap so spend some dollars and sleep well .

Actually the Onan likes to run .
Low hours on one is not always a good thing .


Well if we were camping , for sure the genny would run at night!
But we are just here at the house packing it and learning how to use the thing. On a gas genny, supposed to oil change every 150 hours. That comes up quick if you run it 24x7.

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