New AS Owner + Electrical problem= HELP?!?!

[BeckyAnt]

So, last night we hooked up our new-to-us 1974 Sovereign to AC power for the first time. Initially it did not work at all, so my husband called an electrician friend. He suggested the wires might be crossed in the small breaker box at the rear, so Patrick reversed them and VOILA, the lights came on! We had power for about 20 minutes, and then the lights suddenly dimmed and then went out altogether. Patrick checked the GFI switch on the receptacle outside our house, but it had not been tripped. The fuses appear to be ok as well...any thoughts?

Also, when it happened, we had all the lights on, and we had been testing all the receptacles with a fan about 5 minutes prior. The fan was still plugged into the receptacle on the passenger side of the rear bedroom, but it was not on.

[bullydogsmom]

Did you hear your univolt running? What lights were on? Did you have 12 volt lights on When you plugged into shore power? I believe that the univolt should have started to run to power the 12 volt lights. You also have regular 110 outlets, which is what you had the fan plugged into.

There are lots of electrical guys on here. A little more information and I think they will be able to help you.


Annette

P.S. If you didn't hear a terrrible noise kinda like a wanggggggg then the univolt is not working. believe me you KNOW when your univolt is running.

[HowieE]

First you need to find an Electrician before the one you have kills you.

There is no reason that reversing 110 volt lines would have any effect on the output of the circuit. AC power will provide power in either configuration. However it could have a deadly effect on you if you touch the trailer body while outside and grounded.

First I would check the polarity of the house source and then carry that polarity into the trailer fuse box to be sure the things are safely wired. Once you have ensured the trailer is correctly wired you can then trouble shut things inside.

Keep in mind you have TWO electrical systems in your trailer. 110 volts AC to power house hold receptacles, the univolt power supply, and maybe the 110 volt side of the refrigerator if so equipped. The second system is the 12 DC system. This is powered from the univolt and the batteries. It powers the 12 interior lights, water pump, and refrigerator controls. There is no problem with polarity or safty in the DC system.

As for the original problem of the power failing after 20 mins. I would not venture a guess until I knew the AC power system had been corrected.

[BeckyAnt]

The Univolt was definitely running, but we don't have a battery in there yet. The PO had it sitting in a shed since 1990 and had it winterized, so we're slowly figuring out what has to be hooked back up.

I had every overhead light on and we were hooked to my house's outdoor receptacle via the black three-prong electrical cord (which actually has a plug like a dryer does, with an adaptor to plug into a "regular" receptacle). I'm not really sure about the cord--it looks like a 220 plug but there's a tag on the back of the TT that says "only use 110-125"...so it seems weird to have a 220 plug on it.

The lights dimmed for about 5 seconds before going out completely, and I could still hear a very quiet hum (sounded like it was coming from the Univolt) while it was plugged in, although none of the lights were working. When we unplugged it from the house, the hum stopped completely.

Thanks so much in advance for your expertise!

[HowieE]

The plug you are thinking is a 220 volt plug is more than likely a 110 30 amp plug. If the plug has 3 prongs 2 of which form a V beneath and centered on the third, round plug that is a 110 volt 30 amp plug.

With all the lights on and No battery you may have overloaded the univolt and it opened internally.

Before going any further make sure the 110 volt system id wired correctly. You scared me with the comment of reversing the wires on a 110 volt circuit.

[overlander64]

Greetings BeckyAnt!

Welcome to the Forums and the world of Vintage Airstream ownership!

Originally Posted by BeckyAnt

The Univolt was definitely running, but we don't have a battery in there yet. The PO had it sitting in a shed since 1990 and had it winterized, so we're slowly figuring out what has to be hooked back up.

While a battery isn't absolutely required for the Univolt to function, the Univolt is happier if it is working with a battery in its circuit.

Originally Posted by BeckyAnt

I had every overhead light on and we were hooked to my house's outdoor receptacle via the black three-prong electrical cord (which actually has a plug like a dryer does, with an adaptor to plug into a "regular" receptacle). I'm not really sure about the cord--it looks like a 220 plug but there's a tag on the back of the TT that says "only use 110-125"...so it seems weird to have a 220 plug on it.

With every overhead light in the coach operating, you may have blown one or more of your 12-volt DC fuses. The fuse panel is part of the Univolt and is usually accessed by removing a small set screw from a panel on the Univolt itself. On a coach that is just being brought out of long-term storage, I would be tempted to replace the fuses for the lights even if they didn't look bad as they may be weakened by age.

The shore power cord you are describing is a standard 30-AMP 120-Volt AC RV power cord. Avoid trying to run your air conditioner while using an adapter to get power from a circuit rated under 30-AMPs -- your air conditioner's compressor may protest insufficient power by burning out its compressor.

Originally Posted by BeckyAnt

The lights dimmed for about 5 seconds before going out completely, and I could still hear a very quiet hum (sounded like it was coming from the Univolt) while it was plugged in, although none of the lights were working. When we unplugged it from the house, the hum stopped completely.

The Univolt will only hum when it is connected to shore power. That hum is one of the reasons that the Univolt is usually at the top of the list of things to be replaced on vintage Airstreams. It sounds like one of three things happened either the fuse for the overhead lights blew -- or -- the Univolt has given up the ghost and shorted out part of its transformer equipment -- or -- the Univolt has tripped the circuit breaker it is connected to in the shore power breaker box.

Good luck with your investigation!

Kevin

[BeckyAnt]

Ok, that makes sense (no battery). Does anyone have suggestions on the best battery to use? I'll go pick one up today.

Patrick is going to doublecheck the wires when he gets home. The PO had done some electrical "work" to it (adding two cords that run up through a hole in the floor, one of which ends as an extension cord in the back bedroom and one ends in the kitchen as an add'l two-plug receptacle with a metal box on the end of the cord) so we're definitely going to get it looked at by someone who knows what they're doing.

Is the Univolt something that we could replace ourselves (we're pretty handy with installations as long as we have directions) or is that something you'd advise going to an RV dealer to get replaced?

Thanks for saving us from being fried extra-crispy!!!

[overlander64]

Greetings BeckyAnt!

Originally Posted by BeckyAnt

Ok, that makes sense (no battery). Does anyone have suggestions on the best battery to use? I'll go pick one up today.

In my coach that still has the original Univolt, I typically go to WalMart since the battery's life is limited by the tendency of the Univolt to overcharge the battery. What you are looking for is a Deep-Cycle RV/Marine battery.

Originally Posted by BeckyAnt

Patrick is going to doublecheck the wires when he gets home. The PO had done some electrical "work" to it (adding two cords that run up through a hole in the floor, one of which ends as an extension cord in the back bedroom and one ends in the kitchen as an add'l two-plug receptacle with a metal box on the end of the cord) so we're definitely going to get it looked at by someone who knows what they're doing.

It does sounds like you may have the ingredients in a recipe for a short or other problems in the 120-Volt AC electic system. I wouldn't be terribly surprised if it was discovered that one or more of your circuit breakers in the shore power electic box have been overloaded at some point in the past.

Originally Posted by BeckyAnt

Is the Univolt something that we could replace ourselves (we're pretty handy with installations as long as we have directions) or is that something you'd advise going to an RV dealer to get replaced?

Many Forum members have replaced their Univolts with more efficient battery friendly power converters. The biggest headache with the project is either separating the 12-Volt fuse panel from the Univolt -- or adding a new separate fuse panel. The "preferred" replacements for the Univolt don't include on-board fuse panels so it is necessary to provide an alternate means for connecting the 12-volt system. I had an Airstream dealer replace the Univolt in my Overlander as the original was in a location with very minimal access, but many have performed their own replacements.

Good luck with your troubleshooting!

Kevin

[BeckyAnt]

Ok--thanks, everyone! I'll keep you updated...assuming we do not fry ourselves.

[adonh]

You may want to check with Randy at Best Converter.com. He is a forum member and can answer all of your questions on your Univolt and the best replacement converter if you need one. He also has the fuses that you may need that are sometimes hard to find.

If you are going to have your trailer at home for any extended period have an electrician hook up an RV 110 v receptacle by adding a 30amp breaker to your house breaker box. The 30amp RV receptacle can be found at most RV supply stores. Then you can plug right in and have the power to run your lights and AC. As stated in another post, don't run your AC while hooked up to a 20amp plug with a adapter.

Good luck.

Don 1976 31' Sovereign

BestConverter - Converters, Inverters, Electrical Supplies, Electronics

[maccamper]

Welcome to the forums, you have come to the right place for information. Even though I am sure you would like to get this resolved right away, I recommend you pause at this point and dig into the various threads that you can search through to see what others have done with this issue.

There are differing opinions and options regarding how many and what type of batteries are the best choice. Are you going to be doing much "boondocking", camping where there are minimal services? That's one factor. Will you be using a generator in the future? As long as you are going to be fixing something, it's a lot easier to do it just once, or to build in for future needs now.

Do you have a service manual? if not, I highly recommend that you get one. If you don't have one and would like me to copy the electrical diagrams from mine and send them to you, please send me a private message with your address and I'll get them right out to you. Please let me know if you have the rear bath or center bath model.

Oh yes, if you decide right away that you are going to replace the Univolt, Whatever you do, do not throw away the fuse panel, you will need to reuse it when you put in a new converter, or someone will have to fabricate one from scratch.

Best of luck with the project.

Laird

[Lumatic]

Remember the lights run on 12v not 110. so your Univolt is converting 110 to 12v. One of the first things I would do is put in a 12v battery, even if it a used beater from an auto parts store and see how the lights, etc. work without shore power.

Also just because a glass fuse looks good does't mean it is. You need to use a test light or alternative to test the fuses actually are good. Also, there should be a red polarity light built into the battery compartment. No light is good, red light you have reversed polarity coming from shore power. That should tell you if your 110 wires are crossed. My bet is you fried some fuses. check each fuse with a test light for power at the end it hooks into the circuit.

[tlavergne]

It wouldn't be a bad idea to replace your breakers with new ones. Breakers can wear out. If you do that make sure that you take an old one with you to the hardware store and make sure you get the correct one. If you don't know how to change them have an electrician do it. It is not difficult but electricity is not forgiving, use precaution.
Tom

[maccamper]

That's good advice from Lumatic in the post below. There is a polarity light on your trailer to let you know if the polarity from the shore (or house or campground) power is reversed. On our '74, it is a clear light on the outside of the trailer just above the water heater door (rear bath) If you have a center bath, it's on the street side towards the back. I think Airstream may have changed the location of that light every once in awhile.

Laird

[BeckyAnt]

Thanks so much for all the ideas!!

We have an electrician coming out this weekend, and I'll make sure to tell him what you said.

You're the best!

I'll update you on our progress next week...

[BeckyAnt]

Yep, we took the Univolt out and it is definitely dead. It was actually pretty scary looking--it should have had "FIRE HAZARD" painted all over it!

I was expecting it to be a pain to remove since it was under the oven, but all it took was removal of four screws on the oven, disconnecting the gas line and cutting two wires, and we were golden! (oh, and of course, two strapping guys to pull out the oven...)

We'll be replacing that Univolt VERY soon. Thanks again for all your advice!!

[bullydogsmom]

Originally Posted by BeckyAnt

Yep, we took the Univolt out and it is definitely dead. It was actually pretty scary looking--it should have had "FIRE HAZARD" painted all over it!

I was expecting it to be a pain to remove since it was under the oven, but all it took was removal of four screws on the oven, disconnecting the gas line and cutting two wires, and we were golden! (oh, and of course, two strapping guys to pull out the oven...)

We'll be replacing that Univolt VERY soon. Thanks again for all your advice!!

You might want to save the fuse panel off the univolt, we did on the advice of others here and it made installing the new inverter much easier.

Annette

[BeckyAnt]

We are really good at following instructions!

We have contacted Randy and ordered our new inverter and a new fuse panel!

We bought a 1974 Service Manual

AND

We are keeping the fuse box from the old Univolt as a precaution.

Thanks again to everyone...will let you know how it goes when we hook it all up!