Turned on the front AC unit to test. I have a lot of vibration coming through the ceiling. Pulled the covers and had the DW turn it on. I can see a lot of vibration coming from the motor which has a squirrel cage fan on either side. Has anyone else had this issue? Any one know of any parts numbers for replacement ? It looks like it should be a reasonable repair to make.
Thanks for any help in advance.
Larry
If it hasn't been used for a while might check for mud dauber nests on the exposed squirrel cage. I had that very thing happen to me.
That was what I hoped to find, but alas the fans were reasonably clean. When I had run the AC 2 months ago there was no vibration. It still puts out cold air, just excessive vibration.
Larry
might check the motor mounts still sounds like something throwing it out of balance.
Mud. Dubber
Red tractor, I agree. It turns smoothly and easy by hand but vibrates bad with electricity. I will open it back up and inspect with a mirror. I didn't notice any play in the shafts or end runout. Something knocks it out to where the fan rubs the cage housing.
Squirrel cage blower will vibrate if out of balance. Metal clips are often attached to a blade to balance. Also oil motor bearing with Zoom Spout Oiler may help.
You might take the inside cover off and snug up the mounting bolts it you haven't checked them in awhile.
On my AC unit it was the plastic condenser blower wheel that was deformed, replace with an metal one and problem was solved.
That was the problem on one of the Fixed it.
jor
I did check the mounting bolts. They were all tight. There was a lot of movement on the rubber isolaters when it was running.
Larry
Try moving wheel to center it in the housing. Is it tightly secured to the shaft with an Allen screw or did someone substitute a bolt. Does it have 2 inlets or one? Mine has two and a combination of slightly bent sheet metal and loose insulation was blocking inlet airflow on one side.
Look closely. You might see a oil port on the fan shaft. Our 1989 & 1992 Dometics have oil ports and they are marked "OIL"
But sometimes they are marked "710". LOL
I thought I remember learning that it is not good to snug up the mounting bolts too tight, as that transfers the vibration to the coach. Maybe too tight is the problem!
Thanks for all the input, I will be checking this weekend when I can get back down to the rig. Carol, I agree that to tight would definitely transfer the vibration, but this just started. It has been as quiet as the back one for the last 3 years.
Larry
Just a follow up. Finally got to look at the AC. Found several cracked blades from the outside of the cage housing on the exhaust squirrel cage fan. Figured that has thrown it out of balance. Managed to look inside, and low and behold, just as predicted by Red Tractor and George, a small mud dauber nest on the inside. Cleaned it out and it runs smooth as silk again. Thanks guys. If it weren't for the collective knowledge of this forum and it's members this fun journey would never be possible. Eternally in debt to all of you.
Larry