Air conditioning on Omni/Magnitude

TrankTheFank · 12-11-2021, 05:02 PM

Hi all, I'm new to this forum. We are picking up our Thor Magnitude RB34 next week.

I see a number of folks mentioning that the AC units don't work very well. Someone said that the AC will only work to 15 degrees below ambient temperature. I assume thats in F. Is that true? Have others had that issue? Our current RV can turn into an ice box if we want.

If that is an issue, has anyone upgraded the AC units with any luck?

Thanks all!

DavidEM · 12-11-2021, 06:02 PM

Maybe what someone is saying is that the cold air out of the vents is about 15 degrees cooler than the inside temperature. That is typical for all air conditioners- home, window and RV units.

How cold it gets inside depends on the size of the RV, the size and number of A/C units, the outside temperature, how much cooking is being done inside, how much door opening, etc.

A good RV should be able to maintain 75 inside when it is 95 outside.

David

ducksface · 12-11-2021, 10:58 PM

Roof ac is generic across all platforms all the way from pop-up to Newell.
They have absolutely nothing to do with coach builders.

LarryD · 12-12-2021, 05:47 PM

you'll want a quality outside windshield cover, makes a big difference in keeping the heat out. when you have time you'll want to scope the ducts. Lots of folks find gaps in the styrofoam ductwork bleeding cold air into the roof.

2022OmniRS36 · 12-14-2021, 03:37 AM

I've got a 2022 RS36 and during Thanksgiving in 70-80 degree temps I found it hard to keep cool. I was a bit surprised. I expected it to cool much better. The other thing about the AC which I find disappointing is they carve ducts into the foam insulation. I had foam "snow" coming out of those vents for a week straight and larger chunks stay stuck in the vents.

kwplot34 · 12-14-2021, 03:42 AM

Quote:

Originally Posted by 2022OmniRS36

I've got a 2022 RS36 and during Thanksgiving in 70-80 degree temps I found it hard to keep cool. I was a bit surprised. I expected it to cool much better. The other thing about the AC which I find disappointing is they carve ducts into the foam insulation. I had foam "snow" coming out of those vents for a week straight and larger chunks stay stuck in the vents.

It should have no issues cooling in that temp, do you have good air flow coming out of the vents?
You will get bits of foam out of the vents for a while, for the chunks pull down a vent and remove them.

2022OmniRS36 · 12-14-2021, 03:55 AM

Quote:

Originally Posted by kwplot34

It should have no issues cooling in that temp, do you have good air flow coming out of the vents?
You will get bits of foam out of the vents for a while, for the chunks pull down a vent and remove them.

Yes it seemed like the flow was pretty good. Not amazing. To stop the snow and make it more efficient I blocked all the vents and let the air come direct out of the unit. This helped it blow colder air.

kwplot34 · 12-14-2021, 04:05 AM

I bet the the divider that helps direct the air in both units has fallen down, they don't tape them in place very well.
You will have to pull the plastic panels off the a/c inside the coach, the part that has the filters in it and the area splash vents. You will see the foam divider.

Jimbo56 · 12-14-2021, 10:57 AM

RVairflow.com. These are game changer for ducted systems. Other than this there are several threads on this forum addressing AC upgrades.

Judge · 12-14-2021, 11:44 AM

I did several modifications and upgrades to the A/C units on my SV34 and I have been very pleased with their performance when temps are in the 90's with high humidity.

I also use the WeatherTech Window Cover Kit for the cab and close the curtain for the cab-over to help keep the heat down along with the blinds being down.

While a 15 - 20 degree delta between the return air temp and the air coming out of the unit is common and normal for any A/C unit don't be fooled by the inside temp reading on the diplay.

Thor does not place the temperature sensors in the center of the coach. They put them under cabinets along the wall where there is minimal insulation. You will get some heat radiation along the wall; especially if the sun is beating on the side of the coach where the temperature sensor is located. You will want to use a digital thermometer in the center of the coach to determine the "real" air temperature.

Last year we were somewhere where the outside temp was 90 - 92 but the display inside the coach was reading the inside temp as only 78. I could tell the temp was much cooler inside the coach was lower than 78. I placed my digital thermometer on the kitchen counter top towards the center of the coach and it read 69 degrees.

chunker21 · 12-14-2021, 12:29 PM

As judge said some improvement to the airflow is helpful but the stock A/C units do a good job cooling the RV. Problem is the insulation is poor so the coach doesn't retain that cooling well. The front cap isn't insulated at all and if the walls and roof are like the cap then little effective in those locations. As judge also said the placement of the temperature sensors misleads the HVAC system in the coach. Adding some small fans will help tremendously in maintaining comfort. We got a couple 10-12" cheap Walmart fans, one in cap and 1 in BR. Air movement is important. For the XG32, and likely others, the head of the bed gets hot and thus uncomfortable. We typically run mainly the LR A/C at night with the fan on low not auto because of the noise. BR fan helps.

There are some other A/C threads that link to other threads on some of those airflow improvements. Pictures included.

williamprunty · 12-18-2021, 07:48 PM

A lot of issues but not with the AC. I have the same unit you have, and the AC is not problem I have had yet. The obvious thing is to keep that front shade closed in the day and also the cab curtain closed.

The Gritz Carlton · 12-18-2021, 08:47 PM

Zero issues here. Walls and roof are block foam insulation. A/C will freeze you out on the hottest days. Another huge plus with the F550 is the center dash A/C vents can be turned straight rearward and they will keep the coach body very comfortable while underway without having to run generator using roof units. Quality of build goes up with price of unit. Engine heat and cheaply built front cap of the gasoline Class A's are not an issue with the F550. Those folks roast underway. You will love the coach!

kwplot34 · 12-18-2021, 09:27 PM

The a/c keeping the coach cool on the hottest of days has not been an issue, we do have a small Vornado fan to help air circulation and I suspect since I insulated the cap heat is going to be even less of an issue and the cold.
Not having the gas engine between our legs anymore is a big bonus when driving, the chassis a/c keeps it nice and cold while driving down the road have never needed to fire up the generator to run roof a/c with this coach like we did with the gas engines.

chunker21 · 12-19-2021, 12:27 PM

Quote:

Originally Posted by The Gritz Carlton

Zero issues here. Walls and roof are block foam insulation. A/C will freeze you out on the hottest days. Another huge plus with the F550 is the center dash A/C vents can be turned straight rearward and they will keep the coach body very comfortable while underway without having to run generator using roof units. Quality of build goes up with price of unit. Engine heat and cheaply built front cap of the gasoline Class A's are not an issue with the F550. Those folks roast underway. You will love the coach!

Apparently thor completely changed the way they built your Chateau and how they now build the Omni/Magnitudes. They may advertise "block insulation" but no guarantee it's continuous and zero in the front cap. The actual A/C units work good but poorly insulated house loses the cooling fast. I agree that the dash A/C works great and it's unnecessary to tun the generator and house units normally. This summer we made a trip across central GA in the upper 90s. When we stopped to make some lunch the back of the RV was low 80s. Course when I shut down the engine and cab A/C, the house quickly heated up.

With thor price has little to do with quality. For thor branded RVs, higher pricing just means you wasted more money. If you think that the house constructed on an F550 has a good cap on it, you need to rethink your definition of good. Front caps on the omni and magnitude are poorly constructed and attached. Glad you are happy with your chateau and the quality of it. I'm very disappointed in the omni and the very poor quality of the house. Great chassis, lousy house.

The Gritz Carlton · 12-19-2021, 08:21 PM

chunker...sell it and buy a tent. Life's to short to be unhappy. I didn't get where I am in life by having to "rethink".

kwplot34 · 12-19-2021, 11:33 PM

Chunker is correct that the build quality is pretty piss poor from Thor. I can say that after fixing the front cap on mine there is NO insulation anywhere in the cap, mine is insulted now, the ceiling is insulated with foam can't say for the walls I have not had to dig into the walls, yet. I have too much time and money invested in my Omni to get rid of it, hopefully I have found and fixed all of Thor's shortcomings in their build quality, nope just remembered still have to wire the BIM correctly but that is an easy 10 minute job.
The DW and myself were talking earlier this week about the Omni and if we find one more big fix like the front cap and it's gone, will most likely go with the Nexus then.