On Jan 28, 6:48*pm, (Malcolm Hoar) wrote:
In article , "Bob-tx" wrote:
On our house garage, we have a double light weight steel door and a
Craftsman door opener.

Every time the temperature falls much below about 40 degrees, we
have a problem that only occurs when closing the door.

Metal and cold temps -- think thermal expansion/contraction.

The door goes part way down and reverses. *It has done this for
years, and I can live with it because it seldom gets below 40
degrees here, but it would be nice to fix it, or at least know what
causes it.

Something has contracted sufficiently that one or more of
the safety sensors is tripping and setting the opener into
reverse.

I have lubricated the roller bushings, the door panel hinges, the
horizontal spring across the top, and the drive chain, using a can
of spray lube that says it is designed for garage doors (I know,
sucker). *The door goes up and down easily by hand and is quiet in
operation.

Have you checked the door manually when the temperature is
low? Try it early in the morning before sunrise on a cold
morning -- chances are high you'll find something binding
or catching.

If that fails, you can probably work around the problem
by adjusting the pressure/other sensor sensitivity by
a VERY SMALL AMOUNT. Obviously, it would be foolish to
adjust those controls by a large amount thereby disabling
the very worthwhile safety features that can prevent
serious damage and/or injury.

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar * * * * * "The more I practice, the luckier I get". |
| * * * * * * * * * * * * * * * * * * Gary Player. |
|http://www.malch.com/* * * * * * * Shpx gur PQN. * * * * * * * *|
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If you put to much down pressure on it , it will it the ground and
bounce up.