Buzzing noise??

[Huss5150]

Hi. Recently bought a 2019 miramar 35.2. Have it on shore power. Live in el paso. Got into the 30's a couple nights ago. Now I hear a buzzing noise from underneath. Are there automatic heaters?

[Dan-sr@perra-us.net]

Originally Posted by Huss5150

Hi. Recently bought a 2019 miramar 35.2. Have it on shore power. Live in el paso. Got into the 30's a couple nights ago. Now I hear a buzzing noise from underneath. Are there automatic heaters?

Buzzing? Like the water pump running or something different? When My ACE is connected to Shore power I can hear the converter running sometimes It is not a continuous buzz. It will go quiet, I think the buzzing occurs when charging engages after I have done something that uses 12v power. My converter is located under the bed but I do not hear the buzzing when I am in the bedroom. I only hear it when I am doing something in the "trunk" storage compartment located under the bed accessed from the outside.

I know it is not the Inverter because I turn it off while connected to shore power.

[16ACE27]

Originally Posted by Huss5150

Hi. Recently bought a 2019 miramar 35.2. Have it on shore power. Live in el paso. Got into the 30's a couple nights ago. Now I hear a buzzing noise from underneath. Are there automatic heaters?

Tank heaters are resistive and are not automatic.

Getting into the 30s shouldn't trigger anything, but colling fans like those used in inverters, converters, and some frig installations can make a racket when it gets colder and they first start up.

Probably need to get under the RV and narrow down the noise location. May not even be related to the cold, maybe a relay just decided to start going bad.

[Mark54]

Originally Posted by Huss5150

Hi. Recently bought a 2019 miramar 35.2. Have it on shore power. Live in el paso. Got into the 30's a couple nights ago. Now I hear a buzzing noise from underneath. Are there automatic heaters?

My ATS hums when plugged in
- doesn't know the words..
But it does sound like a relay failure- or the BIM underneath that can make a loud hum too. Representative pic shown (for lithium version) same shape and look otherwise.
My 20AT did that. Very loud click and hum/ buzz sound.

My 20L doean't have a BIM, so no racket like that.

[Bob Nodine]

Originally Posted by Huss5150

Hi. Recently bought a 2019 miramar 35.2. Have it on shore power. Live in el paso. Got into the 30's a couple nights ago. Now I hear a buzzing noise from underneath. Are there automatic heaters?

Could just be the transfer switch. They often hum if the coils are operated by 60 cycle current (which the majority are). Often cold air will transmit sound better than warm air so maybe because the outside temp dropped you can hear it now.