Is it Electricity or Magic?

[casa3805]

We have a 1984, 27ft, Sovereign. Recently purchased. It has had "MANY" mods to the electrical systems over the years as can be evidenced by several "added on" outlets and the liberal use of black tape. (we love it!)
Just got back from a week on the road at 3 different locations. At two sites we used the air conditioning, and at both of those we ran into an electrical issue.
1) We plug into a 30 amp outlet
2) All is well with AC running for several hours and then we notice lights are out or extremely dim.
3) Refrigerator (3 or 4 year old Dometic) also lost power (or at least lost indicator lights) and would not shift to gas mode unless power cord was unplugged from park power supply.
4) Outlets on trailer continued to work (everything plugged in, was still powered up)
5) Fix at park 1 was to place an adapter on end of supply cord and plug into standard 110 supply, at which point lights and reefer powered back up.
6) Fix at park 2 required me to turn on the battery charger, at which point lights and reefer powered back up.
7) Breaker boxes at parks and on trailer were not tripped. Turning on and off had no effect.

Breaker panel in the trailer has three breakers. One labeled "lights", one labeled "circuits" and a double breaker (two tied together) that would appear to be the main. We got back home late last night so I have not yet been outside to check but first guess is a bad breaker on the "lights". But that doesn't seem to make sense with the reefer issue. And why in the world would turning on the charger suddenly complete a circuit if the breaker is bad?

So....electricity or magic? Do I need to hire a wizard or can the forum members start me and my wife on a logical search and discovery path?

[funkill]

I vote: it's "MAGIC" !
I really hate electrical issues and can't be of much help. Do you have a charger in place of the original Univolt converter? The PO of my A/S removed my univot and put in its place a regular auto battery charger....

Laura

[lahrfarm]

It sounds like a 12v problem. I would say your charging system is not charging, battery runs down after several hours.

[Wsmith]

Check univolt Confirm 120 v power Remove all fuses from fuse panel. Connect the black lead of tester to the terminal marked "ammeter red only" Connect he red lead of tester to any fuse clip on the center aluminum bar of the fuse panel. The voltage must be within 13.8 and 14.2 volts. If Univolt is not within these voltages, replace it. If you are using a non calibrated volt meter I would borrow one or check with more than one meter before replacing the Univolt. ( Cheap meters could be out of calibration)

[Wsmith]

The battery charger should be left on. The only time you would turn the battery switch off is if trailer was stored without being hooked up to 120V power.

Plugging the trailer into 120 volt city power with the master switch off will blow the fuses and may damage other 12 volt components.

[casa3805]

Thanks all,
One of the mods the PO did was to pull the two batteries out of the trailer and load in a recliner up front. I have no idea how he got it in. One battery was placed into the tool box on the tongue and the other was never reinstalled at all.
Have to go look and see if we have fuses up there, and if the univolt is still part of the system. Definitely did not know to leave the charger on when connected at the sites. Guess I did not ask enough questions when I bought it. But man oh man arte these things fun!

[casa3805]

Let me ask one more question just to highlight my ignorance. When I am plugged into city power are there still things in the trailer that are running off the 12V system?

[DKB_SATX]

Originally Posted by casa3805

Let me ask one more question just to highlight my ignorance. When I am plugged into city power are there still things in the trailer that are running off the 12V system?

Right, it's just that when you're on shore power (and things are working right) the 12V stuff is working from a converter rather than from the batteries. If you have the original Airstream converter, it's called a Univolt and you'll find many references to it on these forums (and curses and invective and other colorful comments.)

In my '75, for example, all of the lights are 12V. In some older trailers they had both 12v and 120V lights and you could choose which to use if you had 120V power. When I'm on shore power, my converter is charging the battery (if it needs it) and supplying power to all the 12V lights and fans in the trailer, as well as the water pump and the furnace.

[Wsmith]

Originally Posted by casa3805

Thanks all,
One of the mods the PO did was to pull the two batteries out of the trailer and load in a recliner up front. I have no idea how he got it in. One battery was placed into the tool box on the tongue and the other was never reinstalled at all.
Have to go look and see if we have fuses up there, and if the univolt is still part of the system. Definitely did not know to leave the charger on when connected at the sites. Guess I did not ask enough questions when I bought it. But man oh man arte these things fun!

Do you have two small doors close to the floor line on the front of your trailer on each side of the propane tank? If so that is for the batteries. The inverter should be behind the sofa are. You get to it from the inside. I can look up your trailer again. 84,85,86 all lengths all have the batteries in front with univolt and fuse panel behind the lounge

[MrUKToad]

After reading the above, Mr Toad is feeling quite pleased that he's opted for a new, unmodified trailer. Not devoid of problems, I'm sure, at least the factory supplied unit hasn't been "improved" by a (well meaning) amateur!

[jdalrymple]

Most of the devices in our trailers are 12 volt, and need 12 volts even when plugged into shore power.

The AC, microwave, and sometimes a few light fixtures run from shore power only, but most lighting, the water pump, and the furnace run directly from 12 volts.

The control circuits on the refer and the water heater also require 12 volts.

In an unmodified trailer, there is a voltage converter (univolt it is called by Airstream) that converts 120 AC volts to 12 volts DC. This univolt supplies the required power to run all the devices that need 12 volts while one is plugged into shore power. It also charges the batteries. When you unplug, the 12 volt devices continue to function powered by the energy stored in the batteries. The control circuits in the refer sense the loss of 120 volts and switch to propane to continue working. The cooling is provided by the propane flame and the system is managed by the 12 volt control circuit powered by the battery.

As to your problem, it sounds as though whatever device is supposed to supply 12 volts while plugged into a shoreline is not functioning correctly. I read your line about a battery charger. If this is a standard automotive battery charger, it may not supply enough current to both power the trailer and charge the depleted batteries.

For example, most trailer converters supply at least 40 amps and go up from there depending on how many 12 volt appliances are in the trailer.

Good Luck!

[Skater]

I agree with the above posts, but want to say it a bit differently: start following the wiring (as best you can, I know some isn't going to be accessible). Make notes about what's hooked up where. Draw diagrams. I did this with the B190 a while back and it was worth every moment. When something funny it happens it's nice to know how everything is hooked up.

Originally Posted by MrUKToad

After reading the above, Mr Toad is feeling quite pleased that he's opted for a new, unmodified trailer. Not devoid of problems, I'm sure, at least the factory supplied unit hasn't been "improved" by a (well meaning) amateur!

This seemed rather rude. Not everyone can afford - or even wants - a new camper.

[MDSilverado]

Originally Posted by casa3805

Breaker panel in the trailer has three breakers. One labeled "lights", one labeled "circuits" and a double breaker (two tied together) that would appear to be the main.

The charger not being on would seem to identify the cause if the interior lights dimming. However, the issue with the A/C and Dometic are related to the 120v system? I find it interesting that he indicates the main as being a double pole breaker. That, I believe, would indicate the trailer is wired for a 220v. That I know of all AS's were factory wired for 120v from the factory. Anyone else find this curious?

[casa3805]

Whew,
Had to take the morning and go get new tires for the old guy. That is done and now back to the electrical...
WSmith. Yep, I have the two small battery doors in the front,but they have had the batteries removed and only one battery was re-connected just aft of the propane tanks in an aluminum box. It sits on top of the tongue and the charger is in the box with the battery. (kind of a mess right now) The battery compartments themselves were removed to make room for the double recliner the PO put in and the doors were sealed. See pic. I talked to the PO last night and the only way to get to the fusebox is to remove the recliner. This will not be easy... See another pic.
MD Silverado, your post forced me to go back and look again at the breaker box in the light of day. No double pole breaker, my bad, Sorry folks.See pic. two 20 amp breakers on top.
left to right on the bottom. A 30amp labeled "main", then a 20amp labeled "gen circuits", then a 15amp with red test button, labeled "lights".

Heading out to see if I can figure some of this out. Sure do appreciate the continuing info! And I still think electricity is a little bit magic.

[casa3805]

Oh Mr Toad.....We looked at the new ones. I particularly liked the 27ft International Serenity. But we opted for this 1984 specifically because my wife have always wanted to work on something classic like this. It has the dings and dents of a long and fruitful life. It has personality built in by 2 previous owners, and every little idiosyncrasy makes me wonder, where it was and just what went on to cause the mod or repair.. I cherish the old craftsmanship and love the fact that 27 years after the old boy was built, it is still on the road shouting "I am Airstream, Watch me roll!"
PS: Our unit is hosting a Vintage rally in Glen Rose TX next month. Pleased owners of new Airstreams are also invited. Come on by, any reason is a good reason to go Streamin...

[Excella CM]

The breaker panel is for your 110V power. Unfortunately, the fuse panel for your 12v is behind the sofa. Bad news that, since it is an item that should be easily accessible both for trouble-shooting and replacing fuses. Can the sofa be modified to gain access? You need to do something about it.

[Wsmith]

[QUOTE=casacasa3805;977627]Whew,
Had to take the morning and go get new tires for the old guy. That is done and now back to the electrical...
WSmithWSmiththe fusebox is to remove the recliner. This will not be easy... See another pic.
MD Silverado, your post forced me to go back and look again at the breaker box in the light of day. No double pole breaker, my bad, Sorry folks.See pic. two 20 amp breakers on top.
left to right on the bottom. A 30amp labeled "main", then a 20amp labeled "gen circuits", then a 15amp with red test button, labeled "lights".

Heading out to see if I can figure some of this out. Sure do apprefuseboxhe continuing info! And I still think electricity is a little bit magic.[/Silverado

From looking at the interior photo. I think they removed the batteries and univolt to make room for the sofa. All of the DC wiring should still be there along with the fuses. Looking at your trailer photo this modification was made by a 35 year WBCC member.
When you open the small door there should be abs type boxes inside. The key for that box is a Hurd H it has a octigon head. If you need that year key description card let me know.

Wes

[casa3805]

goodness gracious you all got me in trouble... I managed to yank that sofa around and reveal the fuses just about the time my wife came out to show me the new reservations we have at state parks "This Week". Needless to say I will have just enough time to do a quick check of the voltage as explained by WSmith and will put it back together and go.... Campin is more fun than fixin anyway..

[Wsmith]

Where did they put the inverter? Hope its not out in the tongue box unless the added some weather proofing. I am guessing it no longer has the univolt charger in use.

FYI there is usually an area about 8" wide behind the sofa.
Also there is a post on this forum that tells how to mix up a concoction that will take the yellow out of the end caps and other yellow plastics in the trailer.