Front AC won't cool like rear AC, dealer says it's normal

[dbareford]

My 30x3 only came with 1 AC and it wouldn't keep the rig cool, so I added the exact same model to the bedroom after upgrading to 50 amp service. When we got to use them together this summer the front AC was running at least 15 degrees warmer than the rear unit. I used a infrared temperature gun to confirm the temp in the direct output vent. They were basically working against each other.

I have it at the dealer and they are saying front unit works fine and its normal for two units to be that far apart. In direct sun the two units still won't keep the RV cool.

You folks with two units, do yours run about the same temperature?

[tomkatb]

The same unit, the same temp.

Now there are all kinds of other things affecting efficiency etc. ducts etc.

But if you turn the units on and check both outputs, the temps should be the same, tested after a few minutes.

About. 20 degrees cooler than input temps.

If not there is a unit installation problem. Poor duct sealing, bad compressor etc.

In fancy racetrack ductwork with multiple temp sensors, airflow out of registers matters.

[dolfan1981]

We have two AC units and they both run and cool the RV. No differences in the neither units output. Mostly we have them set on the same temperature but sometimes they are 1 or 2 degrees different. In the GT5 the roof has only 1 set of AC vents that both units share. Sometimes we only run the front unit and it blows cool air out of the vents in the bedroom and keeps the camper comfortable.

What they are telling you does not sound right.

[RELHUB]

THAT IS DEALER SPEAK and what they are really saying is they do not want to fix the problem. It is easier to say everything is normal rather then figure out what could be wrong.

If the AC units are the same then the TEMPS should be the same.
On our AC units I can bypass the duct work and direct vent to the coach. My 2 AC units have the same TEMP when I checked them in the bypass mode.

[salwolfe]

Originally Posted by dolfan1981

We have two AC units and they both run and cool the RV. No differences in the neither units output. Mostly we have them set on the same temperature but sometimes they are 1 or 2 degrees different. In the GT5 the roof has only 1 set of AC vents that both units share. Sometimes we only run the front unit and it blows cool air out of the vents in the bedroom and keeps the camper comfortable.

What they are telling you does not sound right.

X2. Our 29’ Georgetown with 2 factory ACs blow at about the same temps, share ductwork and keep the rig icy in hot Texas weather.

[cfo111]

Go up and remove cover you inside see if you have and water in pan most should have some and the fan will have splash maybe the wrong word but it get in the condenser changing the head pressure so cooling is more effective. Now if none is there something is wrong because AC works best when you pull moisture out which makes it more effective. Also check your evaporator coil it sould be hotter at bottom and loose heat as it starting to change from hot gas to a liquid see I start start.

[Walholler]

I have two Dometic 15K AC units, one came with the 5th wheel that is 30 amp, I added the second unit that is on a dedicated 20 amp circuit and is not hooked to the AC ducting in trailer. If running both at same time, I can get the inside temperature down to 70 degrees with an outside temp of 95 degrees. I have checked both units output temperature wise and both are within 1 or 2 degrees of each other. Your RV dealer is blowing smoke in your direction. I would forget the dealer and take it to a independent RV repair facility that does warranty work on AC units. Get approval from Dometic before repairs are begun.

[loyda]

Try not running front a.c. thru duct work. Maybe air flow blocked. Kink in duct?