Community Forums

Jake21 · 08-05-2022, 08:04 AM

08 American Tradition. Sometimes when my rear A/C compressor kick is on, it makes a humming noise for a few seconds and the washer/dryer looses electrical current. Then the washer dryer will come back on a few minutes later. If I turn the A/C off, there are no issues. Any ideas?

TIA

Skip426 · 08-05-2022, 09:41 AM

Assuming 50 amp service and the two appliances in question are on the same leg of power , I have to ask questions .

Is this a new problem , or one you've been dealing with for a while ?

Has this been an issue at more than one RV park ?

Can you duplicate the condition when running the genset for power ?

Have you attempted any kind of diagnosis or repair?

wolfe10 · 08-05-2022, 09:53 AM

To add to Skip's good questions:

What is voltage (VAC) when this occurs?

Jake21 · 08-05-2022, 01:27 PM

Right now i have the dryer on and the A/C. Showing 116 v and pulling 30A.

Yes it is a 50A hook up and it is a new to us coach. I have not tried testing it with the genny. Funny thing is it only happens as night. We can run all three A/Cs with no issue during the day, but when Zone 2 is running at night, it acts up.

I thought maybe the start capacitor was going bad since it seems to struggle sometimes at night, but I replaced it and it did not help.

K7JV · 08-06-2022, 08:47 AM

Look in your breaker panel and see if your Rear A/C and your washer/dryer are on the same breaker. Ours was on our '06 Dynasty, and what you are experiencing is one piece of the load management "system" design in your coach. On ours, the priority was for the washer/dryer. When both were on, both would operate until the current draw on the particular cycle on the washer/dryer would rise above a preset amount at which time it would open the power supply to the rear A/C. As soon as the current would drop below the threshold, the rear A/C would resume operation until the process repeated.

I suspect that your system is working as it was designed to work.

If your rear A/C and your washer dryer are NOT on the same circuit breaker, we need to go back and look further. Do let us know what you find.

Cheers and safe RV'ing.

Jake21 · 08-07-2022, 07:06 AM

Quote:

Originally Posted by K7JV

Look in your breaker panel and see if your Rear A/C and your washer/dryer are on the same breaker. Ours was on our '06 Dynasty, and what you are experiencing is one piece of the load management "system" design in your coach. On ours, the priority was for the washer/dryer. When both were on, both would operate until the current draw on the particular cycle on the washer/dryer would rise above a preset amount at which time it would open the power supply to the rear A/C. As soon as the current would drop below the threshold, the rear A/C would resume operation until the process repeated.

I suspect that your system is working as it was designed to work.

If your rear A/C and your washer dryer are NOT on the same circuit breaker, we need to go back and look further. Do let us know what you find.

Cheers and safe RV'ing.

They are on different breakers. Last night with the A/C off, the washer lost power mid cycle. Then the power came back on. Then off again. So strange. This seems to happen only at night. Perhaps there are power fluctuations at the pole during the night. Again, during the day we can run all three A/Cs and the washer/dryer and my wife can use the hair dryer. The load is right at 50A and we have no issues.

TXiceman · 08-07-2022, 10:02 AM

Does your coach have a load shed energy management system? If it does, this could shed excessive load in low voltage conditions.

Ken

Jake21 · 08-07-2022, 12:26 PM

Quote:

Originally Posted by TXiceman

Does your coach have a load shed energy management system? If it does, this could shed excessive load in low voltage conditions.

Ken

I believe it does. I flew out today so I will confirm on Tuesday. THe voltage has been reading 120 on both legs during the day. Not sure about the nights though.

K7JV · 08-07-2022, 05:07 PM

Ken, the standards in our state for our public utility power companies is 120 volts plus or minus 5%. So anything between 114 volts and 126 volts would be considered acceptable from the regulatory requirements standpoint, if that helps. I would not expect to see issues from any devices as long as supply voltages are in that range.

And I totally concur with what KE5DFR (aka Ken) added. In our coach the load management was done on the individual circuit, itself, as I described earlier. But in some coaches it is done at another level. In either case, the end goal is the same, and that is to manage loads to keep the demand within the capabilities of the supply source and the wiring and devices in the coach. I'm betting with Ken that you have some form of load management causing your A/C to do what it is doing. And if true, what you are experiencing is entirely normal in RV's such as yours.

Jake21 · 08-08-2022, 07:10 AM

If the load management is acting normal, then why can I have 3 A/C’s, the dryer and a hair dryer on without issue. But at night i have only one A/C on and the system acts goofy? Seems like something is amiss.

TIA

K7JV · 08-09-2022, 07:25 AM

Wow, Ken, thanks for your update. I agree that it sounds strange. My car has a programmable button that can open the gate to our subdivision. It seems to work during the first part of the day but rarely works in the late afternoon or evening. It's been that way for months! Similar crazy deal! Is it my car's fault or the gate controller's fault? Pretty much the same sort of issue you are having. Is it your coach's fault or is it the park power supply's fault?

I'm a bit out of ideas why it would work for you some of the time but not at others. I guess at this point, depending on whether your are set up somewhat permanently in your spot or you are on the move, you may find the problem goes away on its own. I hope that's the case. But at the same time I hate it when problems "solve themselves", because they rarely do. I hope you do find resolution, and look forward to hearing what the problem turns out to be, if you do indeed identify it.

But I agree that if you can have all three A/C units actually running and have the clothes dryer actually running at the same time, there should be no reason why it shouldn't work that way all of the time, unless the electric energy provider or the parks electrical infrastructure has voltage issues. That really does sound like the only remains likely culprit. As long as your supply voltage is between about 114 and 126 volts, you really shouldn't see any operational anomalies occurring.

Persistent · 08-09-2022, 08:59 AM

Quote:

Originally Posted by Jake21

If the load management is acting normal, then why can I have 3 A/C’s, the dryer and a hair dryer on without issue. But at night i have only one A/C on and the system acts goofy? Seems like something is amiss.

TIA

It depends on the capabilities of your EMS and the automatic appliances that are running. It also depends on which branch circuits combinations of appliances are connected too.

A 50 amp 240 volt shore power system is a little complicated. It has two hot legs and each one will allow a maximum of 50 amps. One leg can be overloaded and the other not. Next are individual branch circuits. Any branch circuit can be overloaded while others are not.

That said, circuit breakers protect all those circuits. However, circuit breakers require manual reset if they trip.

An energy management system also protects those circuits, but it will reset a circuit when the overload disappears. Some EMS systems are simpler than others. It all depends on the make and model of yours. Do you have a manual for the EMS system?

A/C draw more current when line voltage is low. Of course they draw a lot more current when the compressor is running and a lot less when the thermostat shuts it off.

Electric water heaters draw a lot of current when the heating element is turned "on" by the thermostat. Your washer may trigger the water heater when it fills with hot water. This may cause the washer and dryer to shut down until the water is hot again.

Energy management systems are programmed to prioritize some circuits over others. The strange behavior is probably due to all of these things interacting.

Unplanned Tourist · 08-09-2022, 09:28 AM

My money would be on the power supply.

If everything is fine during the day and the "problem" only occurred during the night, it's got to be the power supply. Is there a huge solar farm nearby?

Jake21 · 08-09-2022, 10:16 AM

Quote:

Originally Posted by Persistent

It depends on the capabilities of your EMS and the automatic appliances that are running. It also depends on which branch circuits combinations of appliances are connected too.

A 50 amp 240 volt shore power system is a little complicated. It has two hot legs and each one will allow a maximum of 50 amps. One leg can be overloaded and the other not. Next are individual branch circuits. Any branch circuit can be overloaded while others are not.

That said, circuit breakers protect all those circuits. However, circuit breakers require manual reset if they trip.

An energy management system also protects those circuits, but it will reset a circuit when the overload disappears. Some EMS systems are simpler than others. It all depends on the make and model of yours. Do you have a manual for the EMS system?

A/C draw more current when line voltage is low. Of course they draw a lot more current when the compressor is running and a lot less when the thermostat shuts it off.

Electric water heaters draw a lot of current when the heating element is turned "on" by the thermostat. Your washer may trigger the water heater when it fills with hot water. This may cause the washer and dryer to shut down until the water is hot again.

Energy management systems are programmed to prioritize some circuits over others. The strange behavior is probably due to all of these things interacting.

Interesting. To clarify, the washer/dryer is not running when this happens. The washer automatically turns on when you plug it in. Once it has power, it will automatically turn off after a few minutes. So power is cutting off to the beaker at night, and then power returns to the breaker which turns on the washer/dryer. (It does not start up, it just turns on). Then the washer/dryer turns off automatically a few minutes later. This cycle happens a few times per night. So the EMS could very well be causing this. I will see if I can find the model and manual for it. We will be leaving parks in a week. Curious if this will continue.