Dreiha Atmos 4.4 Home Install

[Ty J]

Wow I did take picture of Serial and specs. Looking through my pics. R32 Softstart was recommended by Tosot support

[Ronbrink]

Here’s an interesting fact: In further researching the origin of the Atmos 4.4, I learned that Dreiha also offers 2.5 and 3.5 models, 7.5K and 11K, respectively. However, these units are primarily manufactured for European markets and are 220-240v with R410A refrigerant, but still have the same ‘SANZ’ connections as the Atmos 4.4; German designed and foreign made at one of the aforementioned SANZ Clima facilities. I’m even more convinced there is no China connection with these Dreiha products!

 

[Geronimo John]

On 3/29/2025 at 10:48 PM, Ty J said:

Tosot A/C installed

Ty J:  Is this a drain tube?  If so it would be simple to penetrate the hull on both sides and pipe them down via the existing Dometic drain tube.

GJ

[jd1923]

On 3/31/2025 at 6:24 PM, Ty J said:

Wow I did take picture of Serial and specs. Looking through my pics. R32 Softstart was recommended by Tosot support.

Thank you and please verify. When I zoom in on the label, it gets too blurry to see. Does the label state: "Refrigerant R32?"

[Ty J]

Thats my Cell phone booster. I can try to penetrate the gasket if I can find some capture device for the water. Thanks!

[Geronimo John]

34 minutes ago, Ty J said:

Thats my Cell phone booster. I can try to penetrate the gasket if I can find some capture device for the water.

Roger.  Thanks.  

Edited April 6 by Geronimo John

[Ronbrink]

I read this post in SDG’s FB on general humidity control measures and thought these tips may be of interest:

 

 

[Ronbrink]

On 3/31/2025 at 8:54 AM, CRM said:

I'm more concerned with how low the CFM's can go at it's lowest setting for controlling humidity and I couldn't get that info on the Atmos when I was researching it. 

Just an observation. I went to the Cow Barn last Friday to check on the Oliver and run the Atmos on the LFPs in order to drop the SOC below 75%. I do this routinely when in storage for lengthy periods to cycle the batteries and exercise the charging system, which has dual chargers kicking in at that specified level of charge. As the Atmos was running to cool the interior, I referenced the User’s Manual and learned how to operate the Sleep Mode. The unit was whisper quiet and I could only tell when the compressor was running by watching the VictronConnect app as it kicked in. During the interim however, I was also watching the humidity levels as the Atmos cycled in this mode. I observed a 5% fluctuation in the humidity between compressor cycles, which remained steady for the duration of this Sleep Mode test. As it may relate, the interior temperature inside the Oliver was 87° upon arrival (stored inside a totally enclosed storage facility), outside temp was 85°. Because the dehumidifier had shut off due to a full reservoir, a reading of 58% was observed, outside relative humidity was high (>70). During initial operation in Cool Mode, the interior temp dropped to 76° and humidity to 50% in 20 minutes. For the remainder of operational time in Sleep Mode the compressor cycled with a 3° fluctuation in temp and humidity range of 49-54%. 

[Ronbrink]

I came across the following post by a member of the iRV2.com community, by CC220 and dated April 2024, which may be of interest to some. Yes it is very lengthy but interesting, so if so inclined give it a read. As an owner, I concur with this author’s overall assessment of the Drieha Atmos 4.4 and look forward to furthering my personal experiences this coming summer.

 

I just returned from SDG in Elkhart, IN ...after having the Dreiha Atmos 4.4 rooftop AC installed in place of the Dometic Penguin II our Coach House Platinum 220TB had been equipped with. Floridians and others living in the southeast, know full well the sweltering heat and oppressive humidity these climate zones generate in the summer, and their demand for consideration when scheduling outdoor activities and travel plans. Reducing the palpable humidity and creating a light breeze, immensely improves the air quality and comfort coefficient ...even when the temperature is lowered by just 2 or 3 degrees. The prospective ability to mitigate the steamy southeastern summertime 'misery index'...is what originally captivated my interest when reading about the Atmos 4.4 on the LTV FB owner-enthusiast forum. The unit is amazingly quiet, and I could envision an owner mistakenly leaving the unit powered on ...believing it had been turned off. Apparently, there is an 'LED light function' but appears available only when the unit is installed in a ductless configuration. (No part of the actual unit is exposed in our rig's ducted system mounting ...just a flush mounted filter cover. Admittedly, there are some 'unknowns' pertaining to the Dreiha corporation and their products, but obviously not of the type that dissuaded me from purchasing. Dreiha isn't (yet) a household name in this country, and in like fashion; Truma, required several years to attain brand recognition within the RV industry and amongst RV shoppers. Possibly adding to consumer name recognition challenges, is my understanding that the Atmos 4.4 is marketed and sold under another name ...as a virtual twin.  We don't yet have access to sufficient user feedback in this country to evaluate long term reliability, but SDG owner; Kevin Searer's commendable reputation and the very favorable impression I received from him, leaves me confident that product warranty support won't be a problem. I'm glad to see Kevin and his great crew receiving well deserved recognition from the LTV community, and seeing more partnerships developing through which Dreiha brand HVAC products can be distributed, installed and serviced.  To my knowledge SDG has expanded their dealership distribution network into Florida (CTM Customs) and if I recall correctly, a Solar-RV systems company in Texas. I thought it worthwhile to share some test results which compares operational efficiency of the Dometic Penguin II against the Atmos 4.4 AC. When using the Atmos AC function in either 'Dehumidifier' or 'Auto' mode ...its compressor and fan will alternatively cycle on and off during preset work intervals, greatly reducing an otherwise, constant high amperage power draw. The alternating compressor/fan cycle, seems in principal ...somewhat similar to variable speed compressors used in mini-split HVAC systems. That work/rest interval also explains the mind-boggling 'time remaining' estimates (shown in screenshots) produced by my Victron Multi-plus II inverter-charger, when the Atmos 4.4 is operating it's fan cycle in 'Dehumidifier Mode' on battery power. (I only tested using the Dehumidifier Mode, as that is most relevant to my climate zone, while also rendering the longest operational off-grid run times) 28 July 2024, 12:00pm  Elkhart, IN (SDG HVAC parking lot) Ambient temp: 80 degrees, partly cloudy. Battery bank State of Charge: 100% Dometic Penguin II, Set point: 75 degrees  151 amps: High setting, 130 amps: Low setting Time remaining on battery @ present rate: 3 hrs 52 minutes  1 August 2024 8:48 am Columbus, GA  Ambient temp: 77 degrees (With humidity: "Feels like 84 degrees" Weather Channel) Battery bank State of Charge: 100%  Atmos 4.4, Set point: 75 degrees ** Dehumidifier mode Between 77 - 111 amps (compressor cycle) Between 4 - 7+ amps (fan cycle) Time remaining on battery @ present rate: (compressor/fan) Between 6 hrs 27 minutes - 3 DAYS 10 hrs!! Testing initiated with a 4-5 minute compressor cycle, followed by a fan only cycle. ** When compressor kicked off, and circulation fan was activated, amps decreased from 8.55 to 5.21. Just over half an hour into the test, the projected 'battery discharge time remaining' topped out at over 3 DAYS ... while the battery bank State of Charge REMAINED at 97 percent. I documented an unbelievable 35 minutes of AC cooling, with only 28.3 amps used. That current rate of efficiency would extrapolate to over 90 minutes of AC operation ...for less than 90 amps expended. INSANE! At 1:42 pm. Temperature was 94 degrees (With humidity: "Feels like 108" Weather channel) At 4:40 pm. Temperature was 97 degrees  (With humidity: "Feels like 111" Weather channel) Mid-test number crunching & predictions: If the theoretical efficiency deviates little from operational expectations ...my 600ah battery bank would provide 9 hours of CONTINUOUS dehumidifier mode AC run time. The increased ambient temperature clearly altered the rate of energy expenditure, with compressor operation rising to a peak of 111 amps (40a less than the Dometic on 'High' setting) and fan cycle amps at 7+ ... with the alternating cycles appearing to occur in shorter intervals. ** Batteries finally died at 7:15 pm TOTAL run time was approximately 10 hours 15 minutes ** Cost vs performance analysis: The conclusion of testing revealed that the Atmos impressively exceeded the projected run time by more than one hour ...with the battery bank finally signing off after approximately 10 hours 15 minutes. A commonly cited 'AC on battery' energy formula, suggests that a 100ah lithium battery will yield approximately 45 minutes of AC operation. Thus, my 6 x 100ah battery bank would only be expected to provide 4.5 hours of continuous AC runtime.  Consequently, the 10 hours 15 minutes of Atmos 4.4 AC run time ...appears roughly equivalent to having added SEVEN more 100ah lithium batteries. At a cost of $970 each ($6790 for 7 x 100ah Battle Born units) ... OR Installation of the Atmos 4.4 AC, for approximately 1/3 of the cost. I'm no electrical engineer, and therefore unqualified to say with certainty how much impact the three 200w rooftop solar panels may have had on the Atmos' operational longevity, however ...since the 'fan only' cycles of several minutes duration usually required less than 80 watts, I'm led to believe that the solar panels did contribute to the run time. Bearing in mind that the 3 hour 52 minutes of Dometic Penguin II run time was attained while connected to the same 600w rooftop solar array augmenting the 600ah powerbank ...clearly, no advantage was ceded to the Atmos. The Dometic's 'always on compressor' state, imposed significantly HIGHER power demand penalities of between 20-40 ADDITIONAL amps (versus the Atmos') while switching itself from 'low' and 'high' compressor settings.  ** It's vital to consider that the Dometic AC did in fact, have the benefit of operating with the SAME SoftRVstart module (that greatly reduces the inrushing power spike imposed upon the battery bank) as did the Atmos, when demonstrating its superior energy efficient design, by operating in excess of 6 hours longer. The heat pump function on the Atmos not only operates to lower temperatures, and is quieter ...it also reaches set temperature much faster. The bonus feature from my perspective, is the Atmos' remote control interface, providing the ability to function independently from the problematic Firefly system that Coach House has discontinued use of.   True, the wall mounted remotes and bluetooth phone app are viable workarounds for the Firefly's tempermental touch-insensitive main screen interface ...but I prefer the stability of decentralized, direct control of Coach systems. Truma's Aventa and Houghton rooftop AC units offer better performance than the Dometic, but I determined the Dreiha Atmos 4.4 to be the better value. SDG does also sell and install 12v HVAC units and mini-split systems, however ...their increased complexity/mounting space required and lack of a dehumidifier mode, were reasons for me to disregard consideration. Last Saturday, I was surprised to find HVAC technicians at SDG working on the weekend ...they were installing 12v mini-split HVAC systems in 3 Ram ProMaster vans that would soon be serving as ambulances. Beyond installation of a lithium battery bank/3K inverter-charger/optimized DC DC charging system, I now believe that fitment of a substantially more efficient HVAC system (mini-split or next-generation rooftop unit, like the Atmos) ...to be the next most significant systems upgrade one can make for conservation of their rig's vital battery bank power.

 

[Tideline77]

Thanks for posting this information !

we appreciate it very much 

[Teaney Hull 292]

On 3/8/2025 at 7:01 PM, Steve Morris said:

My house, built in 1976 with apparently no building codes observed, is severely under-powered and under-wired. It is an all-electric home with a heat pump for heating/cooling, and only has 150A service. The entire garage is on one 20A breaker, with two wall outlets, one ceiling outlet, and two ceiling light sockets (one of which has a screw-in outlet for four LED shop lamps.)

There are way too many continuous and/or intermittent loads on that one 20A breaker: the aforementioned LED shop lights, garage door opener, 40 year old chest freezer, dorm fridge, stationary air compressor, 3-4 Battery Tender Juniors, the Oliver, an extension cord to my truck to run the fridge/freezer at home, a buried extension cord to an outdoor weather station and security camera, occasional woodworking tools, two Makita 2-slot battery chargers, a Bose Wave radio w/Raspberry Pi attached, cable TV signal booster, and probably more that I'm forgetting.

So, I keep the Xantrax set low to limit how much it draws from the house. The only loads are the fridge, battery charger, parasitic loads, and occasionally the AC. The vast majority of the time the trailer isn't plugged in to the house at all. The batteries can handle any typical loads, and even AC if I'm not using it continuously.

Steve you got it going on in your Garage!

[Teaney Hull 292]

On 3/30/2025 at 12:50 PM, jd1923 said:

Can you please confirm if the Tosot you have runs on R410A or R32 refrigerant? With R32 it means it is equal to the Atmos today. The Gree last year was advertising R410A and it's hard to know what you're getting since this Amazon ad and other sources often do not specify. See this article for the superiority of R32:
https://aircondlounge.com/types-of-refrigerant-in-air-conditioning/

Still a good "Spring Deal" on Amazon now at $1, 020 + tax, delivery included. Wish we lived in one of your no sales tax states! With the high AZ sales tax, this comes to $1,105. The Atmos is $1,350 + $150 shipping + tax (both numbers without StartStart).
https://www.amazon.com/TOSOT-Conditioner-Non-Ducted-Rooftop-High-Efficiency/dp/B0CDWR5RP9/?th=1

The Turbro soft start you show in the picture is $84 plus tax, also on Spring Sale today:
https://www.amazon.com/TURBRO-Installation-Compressor-S15-Plus/dp/B0DK8BXHWH/

OUCH! Just followed the link, not $1,299.99 for Tosot

[CRM]

1 hour ago, Teaney Hull 292 said:

OUCH! Just followed the link, not $1,299.99 for Tosot

Gary-  looks like the tariffs are hitting all of them. Was getting reading to order a Greenland Inverter AC unit and the price jumped $300 overnight. On top of that, now they're out of stock at the moment too. Think I'll wait until the tariff situation is resolved and hope my 16 year old Coleman holds out a little longer... 

[jd1923]

5 hours ago, Teaney Hull 292 said:

OUCH! Just followed the link, not $1,299.99 for Tosot

I'm seeing $1200 with shipping.
https://www.amazon.com/TOSOT-Conditioner-Non-Ducted-Rooftop-High-Efficiency/dp/B0CDWR5RP9/

Still less than $1500 total on the Atmos (with $150 shipping, no SoftStart on either).
https://www.sdgelkhart.com/product-page/atmos-4-4

I witnessed @Ronbrink's installed Atmos and it was excellent. Still not sure the Tosot is of the same quality. Right now, maybe $300 more on the Atmos to be sure with reputable US rep in SDG.

I would love the Greenland inverter A/C that @CRM is also interested in. If I was to learn it is quieter than some reviews show. And I too am waiting another year.

[dewdev]

1 hour ago, jd1923 said:

I'm seeing $1200 with shipping.
https://www.amazon.com/TOSOT-Conditioner-Non-Ducted-Rooftop-High-Efficiency/dp/B0CDWR5RP9/

 

The TOSOT AC is manufactured in China.

Hopefully not at the same factory where the OTT springs are made.

[Teaney Hull 292]

4 hours ago, jd1923 said:

I'm seeing $1200 with shipping.
https://www.amazon.com/TOSOT-Conditioner-Non-Ducted-Rooftop-High-Efficiency/dp/B0CDWR5RP9/

Still less than $1500 total on the Atmos (with $150 shipping, no SoftStart on either).
https://www.sdgelkhart.com/product-page/atmos-4-4

I witnessed @Ronbrink's installed Atmos and it was excellent. Still not sure the Tosot is of the same quality. Right now, maybe $300 more on the Atmos to be sure with reputable US rep in SDG.

I would love the Greenland inverter A/C that @CRM is also interested in. If I was to learn it is quieter than some reviews show. And I too am waiting another year.

Hopefully when my Dometic dies the tariff’s will have settled down. 

[jd1923]

36 minutes ago, Teaney Hull 292 said:

Hopefully when my Dometic dies the tariff’s will have settled down. 

Issue is bearing the noise until then! If I lived in Florida I would have already installed one.

[jd1923]

3 hours ago, dewdev said:

The TOSOT AC is manufactured in China.

I believe they all are, except for the Aussie Houghton A/C (unless they off-shore their manufacturing like the rest). Atmos German designed, China built.