tlsistrunk Report post Posted June 5, 2017 Our #2 roof air has an intermittent, loud , low-pitched rumble that lasts about 5 or 10 seconds, cycling on about every 30 seconds when the compressor is running. It is 47000 series Airxcel. Units 1 and 3 do not produce the same type noise. Any thoughts? Share this post Link to post Share on other sites
desertdeals69 Report post Posted June 6, 2017 I would take the shroud off and have it running and listen to the compressor with a stethoscope that mechanics use to determine where the noise is coming from. It may be something like a loose mount on the compressor or something else loose and rattling. Share this post Link to post Share on other sites
hermanmullins Report post Posted June 6, 2017 Good advice. If you don't have a mechanics stethoscope handy in your tool box try this ole trick I used when I was a mechanic and could not afford a stethoscope. Take a long screw driver and place the blade on the object you want to listen to and put your ear to the handle. You may think you look silly but it works very well. Herman Share this post Link to post Share on other sites
desertdeals69 Report post Posted June 6, 2017 I have used the screwdriver many times. Place your palm over the end of the handle and put your ear on the back of your hand. If the sound is coming from the compressor itself, probably the complete unit needs replacing. Replacing just the compressor is cost prohibitive. Share this post Link to post Share on other sites
wildebill308 Report post Posted June 6, 2017 I would also check the amperage draw of that compressor. If it is hi or fluctuates it is probbabley going bad. Check the blower motor too. Bill Share this post Link to post Share on other sites
hermanmullins Report post Posted June 6, 2017 You might be able to check the blower motor by settings you thermostat on to fan and high. See if the blower is the loud rumble. Herman Share this post Link to post Share on other sites
tlsistrunk Report post Posted June 10, 2017 The day after this post, the fan disintegrated with a loud bang. Parts penetrated the coil, so I now have a new AC unit. My coach has coleman 47000 series ac/heat pumps. Two of the fans (out of three units) have failed in this 15-month old RV. Share this post Link to post Share on other sites
hermanmullins Report post Posted June 10, 2017 Sorry to hear you lost your A/C unit. Several questions, what kind and year is your coach? What size is your A/C? This might give your the opportunity to up size your unit for better cooling and better efficiency. Just a thought. And thanks for letting us know what you found . Herman Share this post Link to post Share on other sites