Diagnosing a Bad Inverter

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Dolce Far Niente

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Recently purchased a 1997 Gulf Stream Sun Voyager, and it appears that the inverter is not charging the house batteries while on shore power or gennie, nor powering the TV or anything else while running on the batteries.

The inverter is a Heart Freedom (I think) and its  monitor panel, which is in a front compartment,  only lights up when on shore power, at which time it says everything is hunky dory.  There are 2 breaker buttons on the front of the inverter, neither of which appear to be popped.  None of the breakers in the power center under the bed are popped.

Everything works fine on shore power and on gennie, except that the battery bank is not getting charged.

I'm no electrician, but I can use a meter. If someone can give me an idea of how to diagnose whether this is a dead inverter or another issue, I would sure appreciate the guidance.  My late husband was the tech whiz in the family;  I just held the flashlight, but now I'm flying solo.
 
Some of the Heart Freedom Combi inverters from that era had an internal glass fuse that is prone to failure in the charging section.  The repair may be as simple as replacing the fuse, I don't recall if they were in a fuse holder or soldered in though.
 
Probably the easiest check is to push the buttons on the inverter to be sure they are properly engaged.  Then with the meter check the DC output voltage.  it should be about 13.6 volts or more to charge the batteries.  There are probably covers over the DC battery lines so be careful and be sure you actually can check the DC voltage at the inverter. Also check the voltage at the batteries.
Let us know what you find.
 
Any idea how old the batteries are?
If they are wet cell batteries, have you checked their water level?
 
An inverter wasn't common on a Sun Voyager, especially in 1997, so I'm wondering if it's just a converter (and not a Heart Freedom).  Let's be sure of what you are looking at before we venture too far afield.  If you don't have a make & model for the unit, take a photo of the remote display and the main unit (near the batteries) and post it for us to look at.  A converter wouldn't light up without shore power present (it's a 120v powered appliance). A Heart Freedom could be an aftermarket upgrade, though, or maybe even a factory option. A 1997 vintage Heart would probably have a Link 1000 remote panel but one labeled "Heart Interface" was available as well. 

As for charging the battery(s), what size/type batteries and how many? House and chassis both. With either shore or genset power active, use your voltmeter to measure the voltage at the battery terminals where the big cables attach. It its 13+, the inverter or converter is trying to charge. If less than that it probably isn't working. However, there maybe a big fuse inline in the cable to the positive terminal, so look for that.  A Heart inverter will also shut itself down if the batteries are internally shorted or have high internal resistance (to avoid causing a fire).

Do you have a manual for this inverter?  If not, here is one for the Heart Freedom Combi. Even if you don't have that exact model, much of the info will be common.http://www.xantrex.com/documents/discontinued-products/freedom_combie_owner_manual.pdf
 
The PUsh button breakers are most likely in the 120 volt output side of the inverter And have nothing to do with DC charging
Does the inverter power things when NOT on shore power??? IF not you have a 12 volt side of life issue. Perhaps the fuse inside. perhaps a "T" fuse outside (I've blown one of those.. Expensive). perhaps a breaker broke    You need a volt meter or test light or both to diagnose.

HOW I DO IT.
I like to use a test light. Easy to read (BRIGHT/DIM/DARK) bright is good. rest. not so good.

Start at battery Make sure it is charged. touch clip to - and tip to +  Bright.. good. Dark. check to make sure test light is good (Re-seat lamp).
Move clip to chassis (non painted part) Still bright good
Move out along the positive wire. teh big heavy one in this case with shore power OFF (unplugged) and Generator off.

When you come to a connector.. TEST. if that connector is on a device that has a 2nd big wire connector.. TEST IT. and continue till you no longer "See the light".
Problem exists between Bright and Dark.

IF YOU GET all the way to the inverter... Look for the fuse inside others have mentioned and .. You guessed it. TEST
 
Welcome to the Forum!

First, allow me to define terms.  A CONverter converts 120VAC to 12VDC to charge batteries and supply power to 12V equipment, like most interior lighting.
An INVerter takes 12VDC from the battery and inverts it to 120VAC to run 120V equipment like Television, sat dish, phone chargers when no shore power or genny is available.

A fully charged battery should produce 12.6VDC with no charging device attached.  A 12.0V output is a 50% or more depleted battery, in need of a charge.  If the CONverter is working, the voltage reading at the battery should be 13.5V or higher.

Measure the voltage at the battery with the converter connected.  Using the numbers above, you can easily determine battery and charger status.

POSSIBLE SIMPLE SOLUTION
As I was typing...Check your battery disconnect switch, often near the entry steps, and make sure it is ON.  If it is OFF, the battery will not charge, but the converter will power the 12V systems.
 
grashley said:
...
POSSIBLE SIMPLE SOLUTION
As I was typing...Check your battery disconnect switch, often near the entry steps, and make sure it is ON.  If it is OFF, the battery will not charge, but the converter will power the 12V systems.
Click to expand...

None of my three coaches would let 12V stuff work with the "salesman switch" off -- it's to minimize battery discharge. They all WOULD let 120 VAC stuff work, though.
 
As Larry says, some RVs disconnect all 12v power, but Grashley is also correct that others may disconnect the battery 12v only and the converter 12v still works. I've owned both types.  If the cables that feed the 12v distribution bus (fuse panel) go direct to the battery rather than being wired to the converter, a battery disconnect  would usually remove all 12v power. Where the 12v bus is part of the converter module or wired to it, then the disconnect only takes the battery out of the circuit and converter power remains available. The latter is more common.
 
As Gary said, and is true in my FW, the 12V power distribution is wired to the battery AND the converter.  If the converter is working and the coach is on shore power, I have 12V power.  If the battery disconnect is OFF, I still have power, but the battery will not charge.
 
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