SOLVED: E7 error code on Front AC (loose neutral)

[VMooreSR]

Got an E7 code on Bedroom AC, Living room AC is fine I checked circut breakers and fuses they all check out ok, what to check next?
Thanks, Vince

 

[rjr6150]

Re: E7 error code on Front AC

Vince
When this happened on ours just flipped the breaker off for a moment then back on all ok since then.

E7 code from the Dometic web site

Loss of 120 VAC power to all power mod- ule boards on the system. The system will shut down.

 

[VMooreSR]

Re: E7 error code on Front AC

Randy,
First thing I did, didn't help

Vince
When this happened on ours just flipped the breaker off for a moment then back on all ok since then.

E7 code from the Dometic web site

Loss of 120 VAC power to all power mod- ule boards on the system. The system will shut down.

 

[VMooreSR]

Re: E7 error code on Front AC

Found the problem, A loose wire on the Neutral Bus bar which had a little melt down, cut out the bad section and all is working as it should.

 

[TacoTom]

Re: E7 error code on Front AC

I am getting the same E7 code on my main unit, I have tried everything, Switched from 30 amp to 50 amp, tried running from the Gen Set, checked all the breakers, as wheel as the gfi's. the other 2 AC (bedroom, garage) work fine. This is our first trip out so no history to go back on.

You mentioned loose neutral..... where do I find that?

Thanks for any help!

Tom

Found the problem, A loose wire on the Neutral Bus bar which had a little melt down, cut out the bad section and all is working as it should.

 

[VMooreSR]

Re: E7 error code on Front AC

TacoTom,Ours is behind the face plate on the circut breaker box.

 

[danemayer]

Before you pull the circuit breaker panel, it's a good idea to disconnect shore power.

 

[TacoTom]

Thanks for the reminder!...I will certainly cut the juice, before screwing around. Would there also be a connection at the AC unit I could check as well, inside/outside?

Tom

Before you pull the circuit breaker panel, it's a good idea to disconnect shore power.

 

[danemayer]

There may be a control box above the air return in the living room unit. If you remove the plastic cover, you'll see a gray box with several connectors. This is where the A/C, Furnace, and Thermostat wiring come together. You'll be on a stepladder or stool, so again, power off is safer.

 

[TacoTom]

E 7 Code on Main AC

OK....I have tried pretty much everything on my main AC unit and it still flashes A7 on the display after approx. 2 minutes. I have 3 AC's in this Cyclone 3800, it is a brand new unit and this is the first trip.
I have tried the following;
Checked the connections on the AC unit,
Checked the connections on he circutt breaker
And then turned the breakers on and off,
Checked the 12 volt fuses,
Tried 30 amp, 50 amp and Generator

What if anything should I try next?

Thanks

 

[danemayer]

I have 3 AC's in this Cyclone 3800

Hi TacoTom,

First of all, I've merged your new thread with the earlier one so all the answers are in one place.

Either I missed it or this is the first time you mentioned that you have 3 AC's. Because of power limitations, only 2 can be run at a time. There's a transfer switch that switches power between 2 of the units. The 3rd unit should be able to run all the time.

That leads to 2 questions: 1) does the problem occur when the other AC units are turned off? 2) have you traced the wiring back to the transfer switch. To find out where the AC transfer switch is located, you might need to call Heartland Customer Service at 877-262-8032 / 574-262-8030. Have your VIN # ready. Or perhaps someone else can chime in with the location.

 

[TacoTom]

Dan

I just tried the main AC with the other 2 units off and still continue to get the E7 error, I Guess I will call HL to find out where the transfer swt is.

When and if I find it what will need to be done?

Tom

Hi TacoTom,

First of all, I've merged your new thread with the earlier one so all the answers are in one place.

Either I missed it or this is the first time you mentioned that you have 3 AC's. Because of power limitations, only 2 can be run at a time. There's a transfer switch that switches power between 2 of the units. The 3rd unit should be able to run all the time.

That leads to 2 questions: 1) does the problem occur when the other AC units are turned off? 2) have you traced the wiring back to the transfer switch. To find out where the AC transfer switch is located, you might need to call Heartland Customer Service at 877-262-8032 / 574-262-8030. Have your VIN # ready. Or perhaps someone else can chime in with the location.

 

[danemayer]

Tom,

You also need to ask them how they wired your unit. I think some units were wired so the living room is always available and the transfer switch powers either the bedroom or the garage. On other units I think they may have set the bedroom to always be available and the switch alternates between living room and garage. I think the wiring setup goes with how you use the trailer. If the garage has bunks that get used all the time, you might want the front bedroom to be primary, and switch between garage and living room. If the garage is an office, you might want the living room primary and switch between bedroom and garage/office.

If you can run both the bedroom and garage units at the same time, one of them is primary and is always available - probably the front bedroom. The other gets power through the transfer switch. And by process of elimination, if you can run both bedroom and garage at the same time, the living room must be powered by the transfer switch and alternates with one of the other units - probably the garage.

So if you can run bedroom and garage at the same time, my guess would be a wiring problem between the transfer switch and living room AC, or a transfer switch failure.

Make sure you're clear with customer service that you're NOT talking about the main transfer switch that alternates between shore power and generator.

 

[TacoTom]

Thanks Dan

I can run the upper bedroom and the garage (w 2 bunks) at the same with no problem so possible could be transfer switch. Should I check the wiring on the other 2units?

Tom

Tom,

You also need to ask them how they wired your unit. I think some units were wired so the living room is always available and the transfer switch powers either the bedroom or the garage. On other units I think they may have set the bedroom to always be available and the switch alternates between living room and garage. I think the wiring setup goes with how you use the trailer. If the garage has bunks that get used all the time, you might want the front bedroom to be primary, and switch between garage and living room. If the garage is an office, you might want the living room primary and switch between bedroom and garage/office.

If you can run both the bedroom and garage units at the same time, one of them is primary and is always available - probably the front bedroom. The other gets power through the transfer switch. And by process of elimination, if you can run both bedroom and garage at the same time, the living room must be powered by the transfer switch and alternates with one of the other units - probably the garage.

So if you can run bedroom and garage at the same time, my guess would be a wiring problem between the transfer switch and living room AC, or a transfer switch failure.

Make sure you're clear with customer service that you're NOT talking about the main transfer switch that alternates between shore power and generator.

 

[danemayer]

I don't think you need to check the other wiring at this point. Once you find the transfer switch, look for the mfg/model info and download the manufacturer's troubleshooting info. There may be some checks you can do (with great care) to determine if it's working correctly.

I would guess there's romex from the circuit breaker box to the input side of the switch, and 2 romex lines from there to the living room and probably the garage AC units. Since one AC unit powered from the switch is working, the input connections are ok. And one set of output connections is ok. With the cover off the unit, being very careful, you can probably use a voltmeter or non-contact voltage tester (better) to determine if the transfer switch is transferring power correctly.

If you share the mfg/model info, I'll post the manuals here on the forum for the next guy.

 

[TacoTom]

I will check back with you on Friday as I have to pack up and Travel tomorrow.

I don't think you need to check the other wiring at this point. Once you find the transfer switch, look for the mfg/model info and download the manufacturer's troubleshooting info. There may be some checks you can do (with great care) to determine if it's working correctly.

I would guess there's romex from the circuit breaker box to the input side of the switch, and 2 romex lines from there to the living room and probably the garage AC units. Since one AC unit powered from the switch is working, the input connections are ok. And one set of output connections is ok. With the cover off the unit, being very careful, you can probably use a voltmeter or non-contact voltage tester (better) to determine if the transfer switch is transferring power correctly.

If you share the mfg/model info, I'll post the manuals here on the forum for the next guy.

 

[TacoTom]

I will check back with you on Friday as I have to pack up and Travel tomorrow.

So I checked the other 2 AC's and repaired 1 loose connection, however I still get the E7 Error, So I called my dealer and Dometic agreed to have an RV tech to diagnose the problem, which they think could be a circuit board Issue, hopefully that will be Tuesday.

I will update this post then, Thanks for all the help thus far

 

[TacoTom]

Dan...you were absolutely correct, it was the connection at the transfer switch!! broken wire inside the sheath approx 1" from the wire end. Probably got bent back and forth to many times or the wire stripper nicked it too deep when the sheath was being stripped... Anyway glad the problem was solved!!

Thanks for the help!!

Tom

I don't think you need to check the other wiring at this point. Once you find the transfer switch, look for the mfg/model info and download the manufacturer's troubleshooting info. There may be some checks you can do (with great care) to determine if it's working correctly.

I would guess there's romex from the circuit breaker box to the input side of the switch, and 2 romex lines from there to the living room and probably the garage AC units. Since one AC unit powered from the switch is working, the input connections are ok. And one set of output connections is ok. With the cover off the unit, being very careful, you can probably use a voltmeter or non-contact voltage tester (better) to determine if the transfer switch is transferring power correctly.

If you share the mfg/model info, I'll post the manuals here on the forum for the next guy.

 

[danemayer]

Glad to hear you found the problem and were able to fix it.