On Mon, 24 Nov 2003 22:17:34 -0500, "CBHvac"
wrote:


"klm" wrote in message
.. .
On Sun, 23 Nov 2003 20:15:02 GMT, "volts500"
wrote:


Switch off the furnace power. Disconnect the fan belt.

FAN BELT??
Geeezeus..I hope his isnt that old..

Try turning
the motor first then the fan drum next by hand.

Fan drum? It better NOT move...



I have a natural gas fired furnace with a label InterCity (iC). The
house is 1400 sq ft, double that if you include a full basement.


The furnace looks as new as the day it was installed and it works
pretty hard what with the 6 month long winters we have up in the great
white north. I keep it well maintained.

The mechanism is as simple as it gets with a 1/2HP electric motor
turning a squirrel cage fan via a pulley and belt. Tried to be a bit
too clever when it was new and added grease to the bronze bearings for
the squirrel cage axle. That grease dried up fast, probably wore the
bronze bearings to give a dirty dark abrasive crud (oxidized bronze.)
I had to change the bearings twice within 3 years before I wised up
and figured that the bearings were meant to run dry. The damaged
bearings were ovalled so that the axle could flop around and the
furnace gave a loud clunk everytime it started up or stopped. It
squealed like a stuck pig when the fan was turning. The furnace had
been running fine for more than 10 years since I omitted that grease.