On 1/18/2013 6:16 PM, wrote:
Our office has a rooftop Lennox THA090 AC unit. It comes with 2
compressors. Almost everyday we have to go to the roof to restart the
compressors because they often will trigger an internal circuit
breaker that protects the compressors. According to the PCB board that
is next to the compressors, when it trips the breaker, it says it is
because of a High Pressure fault (LED1 will flash, and LED2 will be ON
solid). What would cause this fault on a daily basis?
Thanks for any tips!

Here are some pictures of the AC unit:
http://www.flickr.com/photos/54230006@N07/8391891825/
http://www.flickr.com/photos/54230006@N07/8392974016/
http://www.flickr.com/photos/54230006@N07/8392973520/


Are there bubbles in the sight glass when the units are up and running
after 5 minutes or so? Another problem could be dirty condenser coils.
A low charge or dirty coils could cause the compressors to overheat. ˜º

TDD