A year ago I installed a new Dometic Brisk Air 15K BTU A/C unit to replace our old unit. The 5'er has a ducted A/C setup and the new unit fit perfect and works great the majority of the time. Keeps the trailer a lot cooler than the 13.5K BTU unit.
We don't often have to use the A/C but since it was new we've had an occaisional noise.
Here's the problem I need help with. Every once in a while the A/C unit will get this loud vibrating sound like two pipes or pieces of metal are rubbing together. It's loud enough to wake me up out of a sound sleep.
Sometimes I can get rid of the noise by switching from High Fan to Low Fan or vice versa. Other times I have to shut off the A/C unit and wait for a few minutes and then turn it back on.
Saturday night the noise happened several times and I switched the fan or turned the unit off. Finally, the noise didn't come back and the unit was fine the rest of the night and through Sunday (about 12 hours run time) until we turned it off in the afternoon.
Last night the noise came back and it took a few more attempts to finally get it to stop making the noise.
I'm thinking the unit might be iceing up so the compressor is having to work harder and causing the vibrating sound. It just seems strange that adjusting the fan speed makes the sound go away sometimes but not every time.
Any ideas as to the cause.
Jim01 said
06:44 AM Jul 1, 2008
If your unit is icing up, it's usually because of not enough air movement across the coils. Make sure all your vents are open, and do not run the AC on low speed, especially if it is a 3 speed model.
If it's not ice, I would take the top cover off and check all of the clearances around the fan and also make sure there are no pipes too close to anything that could cause the noise. You can usually gently bend the parts a little to create the necessary clearances.
Hope this helps,
Jim
-- Edited by Jim01 at 07:46, 2008-07-01
The Bear II said
01:49 PM Jul 7, 2008
Jim,
You were right. I finally had the chance to go up on the roof today and take off the cover on the A/C unit.
There were two tubes going to the compressor that were rubbing together. It seems when the compressor begins working hard the tubes would vibrate and cause the noise I heard.
I pulled the tubes apart gently and stuck some foam between them and the noise hasn't come back.
Thanks for the suggestion.
It's now quiet in Chula Vista.
The Bear II
RVDude said
11:02 PM Jul 7, 2008
Ahhhh... What music, the simplest of fixes are simply the best!
We don't often have to use the A/C but since it was new we've had an occaisional noise.
Here's the problem I need help with. Every once in a while the A/C unit will get this loud vibrating sound like two pipes or pieces of metal are rubbing together.
It's loud enough to wake me up out of a sound sleep.
Sometimes I can get rid of the noise by switching from High Fan to Low Fan or vice versa. Other times I have to shut off the A/C unit and wait for a few minutes and then turn it back on.
Saturday night the noise happened several times and I switched the fan or turned the unit off. Finally, the noise didn't come back and the unit was fine the rest of the night and through Sunday (about 12 hours run time) until we turned it off in the afternoon.
Last night the noise came back and it took a few more attempts to finally get it to stop making the noise.
I'm thinking the unit might be iceing up so the compressor is having to work harder and causing the vibrating sound. It just seems strange that adjusting the fan speed makes the sound go away sometimes but not every time.
Any ideas as to the cause.
If it's not ice, I would take the top cover off and check all of the clearances around the fan and also make sure there are no pipes too close to anything that could cause the noise. You can usually gently bend the parts a little to create the necessary clearances.
Hope this helps,
Jim
-- Edited by Jim01 at 07:46, 2008-07-01