Converter Clicking, No hot water pressure

Hi All,

I have a 1996 sunline solaris travel trailer.

I recently bought this from someone who owned it for several years.

After hooking up to shore power I started hearing a clicking noise coming from the converter box area. I removed the cover and the fan is not working, it was pretty gunked up with lint and dust which I have cleaned out.

The clicking occurs about every one minute or so. The lights flicker when clicking. Unsure if this is normal, overheating because the fan isnt working (although didn't feel very hot holding hand in front of it) , or something wrong with the thermal sensor/breaker?

None of the fuses are bad and no breakers tripped. I checked the battery as well with a multimeter which was reading 12V
Can't get lights to run on just battery though if not plugged in to shore power

I can't seem to find any manuals on the RV.

Also unable to get hold water via electric, can get it using propane but water pressure dies to a trickle after a few seconds.

I don't really anything about RV's yet, still figuring it out so any help appreciated.