Space saving furnace making a noise

Our space saving furnace is starting to make a whirring, tinny noise. Is this going to be as costly as it sounds?
Thanks,
s
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Not only will it cost a bundle to fix, it won't save as much space in the future. Get it taken care of soon so the space you've already saved is not lost.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
sam wrote:

Did you pull the cover to look at the fan? There may be a chipmunk running around the squirrel cage.
--
Gerald Ross
Cochran, GA
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 13 Dec 2009 01:13:06 -0600, the infamous sam

If you just recently had a snap freeze (ours was down to 11F), it could just be frozen up like mine was. Check your drain pipe for ice. Mine had frozen all the way up into the machine so the combustion chamber had water in it. Luckily, the drip pan caught most of the water when it thawed so my kitchen ceiling didn't collapse from it.
Other problems which can make it sound tinny are:
1) loose insulation blown into the fan. This can also cause a bad vibration during operation. Mice can build nests in systems over the summer, when you're not using them much. Be sure to wear a dust mask or respirator when cleaning up mouse nests to avoid any Hantavirus.
2) loose impeller screws. The fan can vibrate if it's loose, or hit the sheetmetal cover/guard which causes a tinny noise.
3) Bad (or just dry) bearings in the fan motor.
Turn the furnace off and unplug it. Pull the inspection covers and look for crap in the fan. Spin the fan by hand to listen for that tinny noise. See if the motor shaft wobbles. Inspect the covers around the fan opening for wear, indicating a loose or bent impeller. Look for and lube any zerks on the motor and fan assembly.
How old is your system?
Harbor freight has a nifty English wheel if you have to replace a cover due to insignificant scratches. If you wish to fabricate this yourself, this could be a nice tool-collecting problem, this whirring tinny noise, sam. Don't limit yourself to wooddorking tools, expand your metaldorking array, too. Go for it! Enjoy.
--
Don't forget the 7 P's:
Proper Prior Planning Prevents Piss-Poor Performance
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
novalidaddress@di\/ersify.com says...

Hey Larry!
Much appreciated! I'll get to work. The unit is about 15 years old.
s
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I don't know. How costly does it sound now? ;~)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

On my furnace the fan on the inductor fan came loose on it's hub (about a year old). I brazed it up several years ago and it's been fine since. The dealer I bought it from went broke, and I'd have had to pay a dealer to come in and fix it, and then HOPE to get some of it back on Warranty - and the local dealers didn't have the part in stock - so I just fixed it myself.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 13 Dec 2009 15:35:37 -0500, the infamous snipped-for-privacy@snyder.on.ca scrawled the following:

One Atta Boy comin' atcha, clare.
-- Every day above ground is a Good Day(tm). -----------
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.