Mysterious Noise

[Sharon_Jon]

We have a new, intermittent, buzzing/fizzing noise and would greatly appreciate help from the knowledgeable experts on the Forum in elucidating its cause. We have a 2014, 27’ FB International that we have camped in extensively for the last 3 1/2 years, traveling about 50,000 miles.

Our last trip of several months concluded in early November. The noise was not present. The trailer was stored and not winterized in Florida. At the end of January we took it directly to have solar panels and associated electronics installed by an expert. The noise was present once we began camping. It is a sort of buzzing/fizzing, fairly faint sound that seems to emanate from the region of the fuses and circuit breakers. In our trailer this is at floor level under a large drawer below the microwave and between the stove and the bathroom. We have camped exclusively with shore power.

The intermittent noise seems to be present most commonly in the morning and occasionally at other times. We experimented and found that for the noise to occur the refrigerator must be on. Turning on the lights in the bathroom, bedroom and over the sink or dinette table silences the noise; however, turning on the main overhead lights in the cabin did not. The noise is not heard in the water heater compartment accessed in the bathroom.

We would appreciate any advice and help.
Thanks,
Jon and Sharon

[JMynes]

I would check the fan(s) on your converter. Those small computer type fans can buzz if they’re on the verge of being turned on by a thermostatic switch, or if they’re variable speed and not quite ‘on’. If one is faulty it might be buzzy if it’s trying to spin and can’t quite get there.
Look for the fan to be twitching. Give it a spin to see if the noise changes.

[Sharon_Jon]

Thanks for the reply and suggestion. Where is the converter?

[SteveSueMac]

Originally Posted by Sharon_Jon

Thanks for the reply and suggestion. Where is the converter?

If your 14 is like my 12 it's behind the grill near the floor to the left of the pantry.

I was going to work with a friend to swap mine out and ended up having the work done at my local (non-Airstream) RV dealer.

Some suggest it's a do it yourself job but I am not mechanically - and definitely not electrically - inclined. If you're not comfortable doing the work yourself, any RV dealer should be able to help.

Good luck!!

[Sharon_Jon]

Thanks--my fan in same place. It spins fine so will wait for it to come on.

[sgschwend]

Is it more like a squeaking noise?
Most converters are frequency switching power supplies that do make a buzzing sound. The sound would vary with loading. Not sure how to fix that noise.

[Sharon_Jon]

No, not squeaking. It seems best described as vibrating or somewhat high-pitched not real fast buzz. It came on again today. Per JMynes and SteveSueMac suggestion removed grill and it seems to be from around fan area of converter (?) or whatever is shown below. Again turning on lights--this time main cabin lights--silenced it. It was coming and going and touching housing might have also silenced it. Thanks for the continuing help.

[crazylev]

Just a long shot, but is your tv or stereo on? Could the sound be coming from speakers some kind of interference?

[Sharon_Jon]

Good thought, but no. Thanks for the idea.

[Sharon_Jon]

Noise was louder this morning so took off cover and checked again. Coming from converter for sure. Checked record of solar installation and it was new so called factory who said it was defective. Not dangerous to us, battery or RV. Will send new one to replace it.