SDG air conditioner installation

[mountainoliver]

After 8 years of use it was time to retire the Dometic air conditioner. I have looked at several brands and for one reason or another I decided on the Tosot brand which is the same as the Atmos brand and probably others as well. Since last summer the Dometic has been making fan bearing noises off and on and I’ve grown tired of climbing on the roof to oil the motor. After eight years I really didn’t want to replace the motor only to have something else fail so this was an excellent excuse to replace it with a higher efficiency quiet unit. We’ve been traveling out west for the past three and a half months and were passing “close” to Elkhart Indiana so decided to drop in and visit the SDG folks. The entire replacement process was perfectly coordinated and our installer Joe knew exactly what needed to be done. We’ve camped out in their parking lot the night before with 30 amp shore power available. The next morning at 8:00 AM I backed our trailer into their shop and about two hours later the job was done. They even printed a custom cover plate to cover up the holes from the old Dometic thermostat. We were able to sleep through the night with the air conditioner running for the first time in 8 years without having to use earplugs, and to watch television at half volume instead of full volume! The air registers force air towards the front of the trailer instead of most all of the cold air being forced onto the bed area. We’re parked in central Ohio for a few days and it’s very hot and humid but the air conditioner is keeping the Oliver very dry and comfortable. On low fan the unit draws about 9 ac amps. Running from the inverter the inverter draws 94 dc amps.  The Dometic on inverter would draw between 130 - 140 dc amps under similar conditions. We are extremely pleased with the work that SDG provided and with the comfort and efficiency of the Tosot unit. I strongly recommend the folks at SDG for the air conditioner replacement. They have done several Oliver air conditioner replacements and have experience in replacing/installing air conditioners on many different rv types. 

[dhaig]

Thanks for sharing your A/C replacement experience.  The Tosot unit looks very attractive compared to the Dometic.  Would you care to share the cost of the new unit plus installation?  Thanks.

Don

[mountainoliver]

Because of tariffs on imported goods and other variables it would be best to contact SDG in Elkhart directly for a quote. The Tosot air conditioners that I have seen online lately range from just under 2,000 to just over 2,000 plus shipping. There may be some dealers that offer the units for well below the above listed prices. 

[Ronbrink]

On 8/9/2025 at 11:52 AM, mountainoliver said:

We are extremely pleased with the work that SDG provided and with the comfort and efficiency of the Tosot unit.

I am still amazed at the efficiency and cooling power of the Atmos and glad that SDG adopted the Tosot as an in-kind replacement unit due to tariff-related issues. I did not opt for the Cielo Max Breez thermostat being offered at the time of my purchase, even though it was widely used by SDG in their typical Class B RV installs. I have since added this device and find it extremely beneficial in energy savings, comfort and humidity control. If you didn’t opt for the Cielo with this a/c upgrade I would highly recommend adding one, you won’t be disappointed! I think it is also worth mentioning that these 15K units are far superior to the DPll 11K formerly in my OLEll, which was often found marginal at times during extreme heat conditions here in Texas. I was really disappointed to learn after initial purchase that Oliver began putting this smaller unit in the 2020 year model and thus, always my intent to upgrade to a bigger and better unit. No regrets in my choice and certain you will feel the same! 

[mountainoliver]

I really like the unit so far. A little disappointed with the owners manual however. They tell us about certain features but they don’t describe exactly what they do. Curious about Xfan function and I can’t tell the difference between air conditioning and the dehumidifier function. The Cielo thermostat was not mentioned to me but I did notice that SDG had one on the wall in the office area! After using the new unit for about a week now in high humidity I’m really thinking about adding the Cielo thermostat. 

[mountainoliver]

The old Dometic unit was 13,500 BTU, still last year for example, in the southern Arizona desert we were camped in 115 degree weather. The Dometic ran continuously all day from mid morning until late afternoon. If the temperature dropped to the upper 90’s the unit seemed to be able to cycle off and on but close to and over 100 it would not cycle off while maintaining about 75 degrees in the camper. I question buying an air conditioner smaller than 13,000 BTU unless you never plan on camping in the summer or later on selling it to someone who never wants to camp in the summer. Maybe my old unit was having other issues as well, who knows. 

[mossemi]

@mountainoliver  Was SDG able to utilize the Oliver’s internal condensate drain system?

Mossey

[mountainoliver]

No, the internal drain system was abandoned. The condensation now just runs off of the roof. 

[Ronbrink]

21 hours ago, mountainoliver said:

Curious about Xfan function and I can’t tell the difference between air conditioning and the dehumidifier function.

Agree, but understand the owner manuals are universal and state that some units may not have all of the features described. For example: “X-FAN function is only available on some models.” Furthermore, typical air conditioning is the Cool Mode setting wherein the compressor will regularly cycle to maintain a desired temperature and the supply fan runs continuously, which causes humidity spikes when the compressor shuts down periodically. In Dry Mode the compressor runs continuously for the sole purpose of condensing moisture-laden air to reduce humidity. Yes, this mode will chill the air much like Cool Mode, but since the compressor is set to run for a prolonged period the temp and humidity will continue to drop to such a point that it exceeds its function and thus, should then be turned off and the unit switched back to Cool Mode. Before Cielo, I had to use the Dry Mode to buffer occasional humidity spikes during the day, but when asleep at night I would often wakeup to extreme humidity levels at morning. The Cileo’s ‘Comfy Mode’ solved these dreaded humidity occurrences, both day and night! 

 

Edited yesterday at 01:25 PM by Ronbrink

[Ronbrink]

2 hours ago, mountainoliver said:

No, the internal drain system was abandoned. The condensation now just runs off of the roof. 

This may be of concern to some, but we no longer have to worry about clogged condensate drain lines or drip pans causing leaks inside our units, which both Dometic and Truma owners have experienced. After a year of use, I find no issue with the roof runoff.

[Patriot]

8 minutes ago, Ronbrink said:

This may be of concern to some, but we no longer have to worry about clogged condensate drain lines or drip pans causing leaks inside our units, which both Dometic and Truma owners have experienced. After a year of use, I find no issue with the roof runoff.

3 years in and zero issues with the Truma Aventa condensate lines clogging here. We just make sure that our trailer is dead level and all is good. 😊 As I recall I never had issues with the “Demonic AC” either. 🤔 

[Ronbrink]

2 minutes ago, Patriot said:

3 years in and zero issues with the Truma Aventa condensate lines clogging here. We just make sure that our trailer is dead level and all is good. 😊 As I recall I never had issues with the “Demonic AC” either. 🤔 

Understood, I never had a leak issue with my Dometic either nor too concerned about being “dead level”. Some however, have not been as lucky! 

[Patriot]

2 minutes ago, Ronbrink said:

Understood, I never had a leak issue with my Dometic either nor too concerned about being “dead level”. Some however, have not been as lucky! 

Ron, you mean Demonic Penguin? 😄 That’s what I use to call that loud jet engine…lol. Sold my old Demonic to a guy with a food truck for $600 after hauling it back from Oliver post Truma install.  

Edited yesterday at 01:56 PM by Patriot

[Ronbrink]

5 minutes ago, Patriot said:

Ron, you mean Demonic Penguin? 😄 That’s what I use to call that loud jet engine…lol. Sold my old Demonic to a guy with a food truck for $600 after hauling it back from Oliver post Truma install.  

I like your play on words, “Demonic” indeed! Sold my DPll 11K for $600 as well on FB Marketplace in short order.