Flapping noise behind microwave

[iezzif]

My rig is a 2003 Itasca. Trying to figure out what is making a loud metallic flapping noise behind the microwave oven when the wind kicks up. I know that there is a louvered plastic flap on the outside of the vent, but its not the source. Any clues?

[ThomB]

There is a vent on the outside that has a cover that should only open when air is coming from the inside (*when you're using the vent hood/ Microwave). That's likely the sound you are hearing. Ours does the same, drives me nuts, and if you know how to correct it (anyone) I'm willing to listen.

[powercat_ras]

I used some self stick felt discs to muffle it. You get on a ladder and manually move the flap in and out and put the felt discs where the flap makes contact.

[be happy]

The folks that owned my Meridian before me installed a length of self stick carpet the length of the vent. No noise when moving or wind.

[iezzif]

Thank you all, but it is not the outside flaps. There is something else inside the coach that is causing the noise

[CWHTRAINS]

I know this may sound strange, but how close is your refrigerator vent on the roof to the microwave? On a trip out west one time, we kept hearing a flapping noise when driving occasionally as well in high wind conditions. Finally when out in the winds of Montana during a trip we heard the noise even when we were stopped on the side of the highway. Drove me nuts thinking it was the microwave vent flap.

It turned out in my case it was my Norcold refrigerator roof vent. I climbed up on the roof and found the front two screws holding the refrigerator vent to its mounting frame were gone and while I was on the roof I watched as the wind was picking up the front of the plastic vent cover about two inches or more and then it would drop back down making the banging sound. We were in probably 40 mph winds at the time. I was able to get the rear two screws out and climb back down with my roof vent still in one piece despite the wind. Once at the campground shielded by trees I was able to reinstall it. Good luck.

[CWHTRAINS]

If you think it is inside the motorhome, then the likely cause would be in the area from the internal microwave exhaust fan and the exterior wall vent to the outside. If you think the sound is coming from that area then your only recourse would be to dismount the microwave and check the internal fan area on the top, center, rear of the microwave. Not the easiest job, but doable with some help assuming you can get to the mounting screws holding the microwave onto the wall bracket.

[Bo Walker]

Jezzf, Remove the stove hood filter with a flashlight, look up and toward the outside to see the metal flap I think you are hearing. A wasp next stopped my from making noise. I removed the hood filter, then the fan. I was then able to remove the metal flapper and remove the wasp nest. It all was a pretty easy job.

[JoeC]

Be sure to repair or replace the sticky felt on the stovetop exhaust flapper as this is what keeps the flapper silent as it flaps in the wind, driving down the road or sitting out a good storm. Mine kind of slipped down a bit exposing the metal to metal contact and annoying noise while driving down the road.

[John Mo]

Originally Posted by Bo Walker

Jezzf, Remove the stove hood filter with a flashlight, look up and toward the outside to see the metal flap I think you are hearing. A wasp next stopped my from making noise. I removed the hood filter, then the fan. I was then able to remove the metal flapper and remove the wasp nest. It all was a pretty easy job.

Bo is correct. That metal flap drives me crazy too and it's been noisy since I bought mine new.

I haven't figured out a permanent fix yet, but when I remember, I take off the hood filter and stuff a paper towel through the fan blades and into the flap.

[Reniram]

Just this last week I got around to try to find the noise from our microwave oven..I took all the screws out and carefully pulled it out and noted that the power cord went through the side wall of the cabinet.. Turned out the culprit was the wires going to the LED light that that is for the regular gas stove which is beneath the microwave.. they were coiled on the tinware and any time we hit a bump in the road they made a tinny noise..There was also a square of sheetmetel that the microwave is supposed to sit on and that was just thrown in there with no screws or glue and this probably amplified any other noise.. anyway I ended up putting a wooden support shelf for the microwave and taped the wires and glued a sound deadening insulation to the tin shelf...No more noises...It is pretty dreadful the way our RVs are put together,