I found this out when testing one of these blowers. It overheated unless the
airflow was restricted. I expected the motor load to decrease when the inlet
was restricted but was surprised that restricting the outlet had the same
effect.
Don Young
"Wayne Cook" wrote in message
...
On Sat, 10 Sep 2005 19:39:14 GMT, Gary Brady
wrote:

Not long ago, I made a shop fan from squirrel cage fan out of a
residential air handler. Last weekend was particularly hot, and I had
the fan running most of the day. When I went out to turn it off, the
fan was running but there was a puddle of oil underneath it. Now, or
course, it won't start. I assume the capacitor blew up or leaked.

Can a fan such as this be used for continuous use, or is it only suited
for on and off operation, as occurs in the normal cycling of an air
conditioning unit? Was this just the capacitor's time to go? If I
replace the capacitor, am I just throwing money away?


The biggest mistake most people make when making one of these the
first time is that they fail to put a restriction in the outlet. These
fans are designed to run into a restricted outlet (the coils, and
ducting of the system). If you run one wide open on the outlet without
the restriction it tends to overload the motor since there's to much
air moving over the squirrel cage.


Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook/index.htm