Converter fan comes on when lights in cabinet are on

we have a new to us 2009 Sundance 315 bunkhouse.
DW noticed a fan noise when she turns on the outdoor light and the kitchen light switch in the cabinet above the fuse power /fuse box.

when i hauled out the converter i turned the switches off and the fan stops.
when i turn them on again (regardless of which one first) the fan on the convertor comes on.
it stays on until both light switches are turned off.

Does anyone else have a similar event occurring and has anyone else had this and found out why?

its kind of annoying since its right at the noise decibel that i can hear really well. (18.5 yrs of police service, sirens, barking K9's and firing ranges)

i would have used the "ask the factory" but i generally haven't memorized my VIN for the unit.

thanks

I have noticed that my fan comes on no matter which lights you turn on. I have no idea why.

Probably because its charging the battery.

How old is the battery. You might try metering in battery with the converter not running (e.g., not hooked up to shore power) and the lights on and see what the voltage is. If it is 12 volts or less, then your battery is probably marginal and not holding a charge very well. In that case the when on shore power, the converter's charge wizard detects the low voltage and automatically comes on to compensate for the added load of the lights.

pegmikef said:

How old is the battery. You might try metering in battery with the converter not running (e.g., not hooked up to shore power) and the lights on and see what the voltage is. If it is 12 volts or less, then your battery is probably marginal and not holding a charge very well. In that case the when on shore power, the converter's charge wizard detects the low voltage and automatically comes on to compensate for the added load of the lights.

Click to expand...

I agree also.

the battery is 1 month old... full charge.

While on shore power, take a voltage reading across the battery terminals. Should be around 13.5V DC. If less than 13.0 V, the battery power is not getting to the fuse box and the converter is running all your DC gear all by itself. If less than 13.0 V, try resetting the 12V DC mini-circuit breaker near the battery.

the guys at Heartland tech have no idea. never heard of this.
he did ask how old the battery is but when i told him a month old and it is fully charged he was stumped.
I mentioned that I don't appear to be the only one and that its almost like the fan to cool the processor on the converter is tied to the switch.

they held their own TECH support Forum and came back to me with how many lights are on in the trailer? they figure that if i / we are running other 12 volt items that the extra light's draw is sending the signal for the fan to energize and cool the board.
My plan this weekend is to swap out most of my regular bulbs for LED's and i'll post what that does for the cooling fan coming on sit rep.

Since your rig is a 2009, there is a chance that the converter is about to fail.
Just before my converter died in my 2011 one of the symptoms was the fan running often. The other was that the lights dimmed and got bright often..
Then one night they went dim and never got bright again.
New converter.

Peace
Dave

danemayer said:

While on shore power, take a voltage reading across the battery terminals. Should be around 13.5V DC. If less than 13.0 V, the battery power is not getting to the fuse box and the converter is running all your DC gear all by itself. If less than 13.0 V, try resetting the 12V DC mini-circuit breaker near the battery.

Click to expand...

will do that tomorrow night... and i just happen to have 2 extra mini breakers in the cabinet just in case.

Thanks Cookie
what unit did you replace the dying one with?
I probably should start another thread on converter replacements if one isn't still open
I just got looking on this site.

http://www.bestconverter.com/45-Amp-4-Stage-Main-Board-Replacement_p_521.html#.VeheuCVViko

My fan would come on with ANY load. Defective converter was replaced.

If the converter that you linked to meets the requirements of your Sundance, it should work just fine.
The needs of my Bighorn are a bit different than yours.
Mine came from Progressive Dynamics.

Peace
Dave