Just noticed that when the furnace is on the fan makes a noticeable change in pitch and the lights in the rv go up and down correspondingly. Is this an indication of a problem with the furnace or the power unit in the rv? We have been at 4 different parks in the last week and it happened at all of them - both 50 and 30 amp service. Thx.
danemayer
Well-known member
Hi Martind,
The furnace and lights run off 12V DC which is powered by a combination of Power Converter output and Battery output. The Power Converter changes the 110V AC shore power to 12V DC to help run the 12V devices and to charge the battery.
If the lights dim when the furnace runs, it may be that there's a problem with the Power Converter, or perhaps you're not getting power from the battery. There's a 12V automotive style circuit breaker in between battery and Power Converter. If it trips, the battery won't get charged and won't supply power to the fuse box. In that scenario, all your internal 12V devices like furnace and lights are powered entirely by the Power Converter.
Usually, the Power Converter has sufficient output to run all the interior 12V devices, so there's a good chance that's where the problem lies. If the Power Converter output is low, it won't supply enough power to run everything and may not be charging the battery adequately either.
We have an owner-written 12V Block Diagram and Diagnostic Guide that might be of help.
The furnace and lights run off 12V DC which is powered by a combination of Power Converter output and Battery output. The Power Converter changes the 110V AC shore power to 12V DC to help run the 12V devices and to charge the battery.
If the lights dim when the furnace runs, it may be that there's a problem with the Power Converter, or perhaps you're not getting power from the battery. There's a 12V automotive style circuit breaker in between battery and Power Converter. If it trips, the battery won't get charged and won't supply power to the fuse box. In that scenario, all your internal 12V devices like furnace and lights are powered entirely by the Power Converter.
Usually, the Power Converter has sufficient output to run all the interior 12V devices, so there's a good chance that's where the problem lies. If the Power Converter output is low, it won't supply enough power to run everything and may not be charging the battery adequately either.
We have an owner-written 12V Block Diagram and Diagnostic Guide that might be of help.
Have you maintained the battery?
Kept the electrolyte level up and cleaned the anodes (terminals)?
There is also a good chance that your converter is on it's last leg.
Try using a battery charger in place of the converter.
That will tell the story on the converter,
Peace
Dave
Kept the electrolyte level up and cleaned the anodes (terminals)?
There is also a good chance that your converter is on it's last leg.
Try using a battery charger in place of the converter.
That will tell the story on the converter,
Peace
Dave
wdk450
Well-known member
The battery acts as a "storage reservoir" across the 40-60 amps of 12 volt power the converter can put out. It also acts as a smoothing filter absorbing any small variations in the 12 volt converter output. But the battery can instantaneously source hundreds of amps (starting a diesel truck takes about 200 amps).
Think of the converter as a water hose; the battery as a 10 gallon water drum. So most of the time when you are on shore power you never use enough 12 volt "hose" current to call on the "drum" - Rather the "hose" supplies all you need and is topping off the "drum" to boot. The "drum" reservoir is there for when you don't have shore power to run the "hose" and you need 12 volt flow.
Think of the converter as a water hose; the battery as a 10 gallon water drum. So most of the time when you are on shore power you never use enough 12 volt "hose" current to call on the "drum" - Rather the "hose" supplies all you need and is topping off the "drum" to boot. The "drum" reservoir is there for when you don't have shore power to run the "hose" and you need 12 volt flow.
OK, great info, thanks for all of that everyone. I did not understand the separation of the 110 and 12 v systems, now I do. So this is what I did...
. checked the battery - connections tight and fluid levels correct.
. pushed the reset button on the circuit breaker - don't think it had tripped
. disconnected the 110 power source, turned on a bunch of 12 v lights and the furnace. The battery is now running everything and it was solid and bright. No fluctuations.
. reconnected the 110 and disconnected the battery - same test. This time the 12v system crashed! restarted within 5 seconds and 5 seconds again crashed.
. reconnected the battery - system continues to fluctuate but not crash.
My conclusions - the battery is good and the converter is failing. Comments?
So, what does the converter look like and where would I find it and how much would it cost to buy a new one? I am sure I can replace it myself.
I have 2011 Sundance and the 110 power comes in the back behind the fireplace. The 110 breaker panel and the 12 v fuse box are beside the sink (connections under the cupboard). I see nothing plugged into an outlet under the cupboard nor in the basement.
Thanks again for all the help... Dan
. checked the battery - connections tight and fluid levels correct.
. pushed the reset button on the circuit breaker - don't think it had tripped
. disconnected the 110 power source, turned on a bunch of 12 v lights and the furnace. The battery is now running everything and it was solid and bright. No fluctuations.
. reconnected the 110 and disconnected the battery - same test. This time the 12v system crashed! restarted within 5 seconds and 5 seconds again crashed.
. reconnected the battery - system continues to fluctuate but not crash.
My conclusions - the battery is good and the converter is failing. Comments?
So, what does the converter look like and where would I find it and how much would it cost to buy a new one? I am sure I can replace it myself.
I have 2011 Sundance and the 110 power comes in the back behind the fireplace. The 110 breaker panel and the 12 v fuse box are beside the sink (connections under the cupboard). I see nothing plugged into an outlet under the cupboard nor in the basement.
Thanks again for all the help... Dan
The power converter should be located behind the basement wall.
CLICK THIS LINK to the manufacturers web site.
Depending on what model you have the price will vary.
I think that they have an offer to refurbish your converter for a bit over $100. Give then a call to verify that.
Once you get the wall down and locate the converter it would be a good idea to insure that the wires are held tight.
I would also unplug the converter and use a battery charger for a while. This will tell you if there might be a problem somewhere else.
When my converter died I used a battery charger for about three weeks.
Peace
Dave
CLICK THIS LINK to the manufacturers web site.
Depending on what model you have the price will vary.
I think that they have an offer to refurbish your converter for a bit over $100. Give then a call to verify that.
Once you get the wall down and locate the converter it would be a good idea to insure that the wires are held tight.
I would also unplug the converter and use a battery charger for a while. This will tell you if there might be a problem somewhere else.
When my converter died I used a battery charger for about three weeks.
Peace
Dave
Dave, I haven't found the converter yet, but once I do and unplug it, where do I connect the battery charger? I am concerned that the converter may fail before I can get it fixed - if this happens I need some way to generate 12v to keep the furnace running, it is below freezing out right now (I am in New Orleans).
... Dan
... Dan
wdk450
Well-known member
BTW, I would think that you would have an AC circuit breaker labelled "Converter" which should switch off input power to the 12 volt converter/charger.
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The converter is operating properly. You have exceeded the output of the convertor. What you are experiencing is circuit overload. On then off, on then off. That is a circuit breaker tripping and resetting. Depending on the size of the convertor, it is possible to have enough stuff on to exceed its recommended output. That is why it is important to have the battery in the loop.
wdk450
Well-known member
Hoeffler's analysis sounds very plausible, especially if you have a discharged or bad battery (that would draw excessive current from the converter). It might be worthwhile to disconnect the battery and run the system on converter only to see if this is a root cause of the variations. If things run O.K., then I would think about getting another battery. Any chance the battery got frozen?
