what does "shed' loght mean at the ac heater controls switch mean?

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STonyG

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the shed light at the rear ac lights up when it is hot. what does this mean
 
"Shed" means the EMS (Electrical Management System) is turning off one of the power hungry A/C compressors to keep the power consumption within the limit of the 30 amp shore power source.  You only notice this in hot weather because it's rare to have both A/Cs running otherwise, or if they are both on, the compressors are cycling on and off so they aren't both on at the same time.

Your EMS may only have the A/Cs connected to it.  More sophisticated systems will shed other things first to lessen the load like turning off the electric hot water heater element and AC power to the refrigerator so it reverts to gas operation.

Plugging into 50 amp service, if your RV has a 50 amp plug and cord, will eliminate the shedding since there is enough power available to run everything at once.
 
Yes. Each a/c requires about 12 amps to run, but each momentarily uses2x that every time the compressor starts or restarts. 30A isn't enough power to reliably run both at once.  If one is running (12 amps) and the 2nd tries to start, total power considerably exceeds 30A and would quickly trip the shore power breaker.  In your coach, the thermostat is also a power management device, monitoring the amperage in use and shutting down one a/c if the sustained power consumption will exceed 30A total.
 
You've gotten good answers.

However, I would (and do) turn them both on  if needed and let the EMS do its job.

Tom
 
Coaches with 30 amp service have successfully run both ACs at the same time for years. You must have your batteries fully charged, your refrigerator on propane and your water heater on propane. Your EMS, your circuit breakers and even fuses have some delay that will allow the current in rush needed to start the second compressor.
 
Coaches with 30 amp service have successfully run both ACs at the same time for years.
Click to expand...
Some can manage it, others not.  Among those that can, it may not work all the time, i.e. trips a breaker intermittently. The presence or lack of a hard start capacitor in the a/c unit is a significant factor (reduces start-up current). So is the line voltage of the 30A power source - a full 120v works better than a shabby 106v.
 
Gary RV_Wizard said:
Some can manage it, others not.  Among those that can, it may not work all the time, i.e. trips a breaker intermittently. The presence or lack of a hard start capacitor in the a/c unit is a significant factor (reduces start-up current). So is the line voltage of the 30A power source - a full 120v works better than a shabby 106v.
Click to expand...

Please expand on "Some can manage it, others not." Which coaches can not and why. Hard start capacitors are not OEM installed. So that is not a consideration when talking general 30 amp systems being able to run 2 ACs. If a shabby 106 volts exists, then you shouldn't be running either AC. I still contend 30 amp systems with EMS will be able to run both ACs under normal conditions. That is the OEMs intention when installing EMS.
 
I am hooked up to my home power. I tried the ac and the shed was flashing. I used the generator and the same results, never had a problem using the generator. I would like to trouble shoot as much as I can before having someone come over and take a look.
Please, point me in the right direction.
 
I'm guessing your have the Intelletec ECC (Electronic Climate Control), which combines twin thermostat with electrical load management for the a/c units.  Load shed occurs when the available power is inadequate for two ac units.  It is designed for 30A shore power and can't manage properly if plugged to 15A/20A source. The two attached pages describe each of the two versions of this system.
The most likely reason for a shed light with only one a/c operating is some other large load is drawing amps.
 

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  • Intellitec ECC_1-5300591.597.pdf
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  • Intellitec ECC_2-5300855.856.pdf
    176.2 KB · Views: 15
I have this set up.
00-00591-000 Master Controller
00-00597-000 Display Panel

I went to a website "just answers". The service guy walked me through, on the phone, on how to check the voltage at the breakers (114-115) and the 12 volt fuses.
He explained to me that the controller is run off the12 volt side.
I am going to have the couch batteries tested today and clean up the terminals. those batteries are 3 1/2 years old.
 
That's the ECC-1 system in my post. 

Yes, the controller runs on 12vdc even though its purpose is to manage 120vac.  Testing the battery won't prove anythng because 12v isn't an issue here - the controller is working and it has decided that total power consumption is about to exceed 30A, so it has "shed" (eliminated) part of the amp load that it controls so as to prevent that.  Besides, the battery isn't supplying the 12v when you are plugged to shore power - the converter/charger is handling that.

Does one a/c "shed" or both?  You mentioned the rear a/c sheds, but anything else?  What were the results when you checked voltage at the breakers?  Are the results the same whether using generator or the 30A outlet? What mode is each a/c set to, e.g. auto-cool, hi-fan, etc.
 
Lou Schneider said:
"Shed" means the EMS (Electrical Management System) is turning off one of the power hungry A/C compressors to keep the power consumption within the limit of the 30 amp shore power source. You only notice this in hot weather because it's rare to have both A/Cs running otherwise, or if they are both on, the compressors are cycling on and off so they aren't both on at the same time.

Your EMS may only have the A/Cs connected to it. More sophisticated systems will shed other things first to lessen the load like turning off the electric hot water heater element and AC power to the refrigerator so it reverts to gas operation.

Plugging into 50 amp service, if your RV has a 50 amp plug and cord, will eliminate the shedding since there is enough power available to run everything at once.
Click to expand...
I know this is an old post but my aquahot went to "shed." I have nothing running, no ac, no heat, no dishwasher or washing machine! We have 50 amp so I don't know what is wrong. Any suggestions?
 
A bit more info on your RV might help. Apparently, since you have Aqua Hot, it's a Diesel Pusher (DP). Are you running the electric heater(s)? Mine had a high and a low position for running electric heat, so if you have that, which way are you running it, high or low? Also, have you tried it when running only the diesel burner?

You might also mention which type/brand of controller that is giving you this indication.
 
mccarmc said:
I know this is an old post but my aquahot went to "shed." I have nothing running, no ac, no heat, no dishwasher or washing machine! We have 50 amp so I don't know what is wrong. Any suggestions?
Click to expand...
PLEASE................ start a new thread, THIS LINK is the Start a New Thread button in the General Tech forum, then you can give it an appropriate title and fill us in on the type of RV and the devices and appliances you are having issues with. It will save folks wading thru an older thread, and allow us to cut to the chase........

Oh, and welcome to the RVForum, its a great place with some knowledgeable and helpful folks.

Charles
 
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