My XV90 upflow furnace gives a 9 red flash code when it starts up. My installers guide says it is an "Open Inducer Limit switcch". The furnace works OK, should I be worried about this?

Only be worried if he bypasses the limit switch.

Our 3 yr old xv90 gave off the same code when it stopped overnight. Had a repairman out who quickly saw that the tube that expels the water was frozen at the tip, causing the unit to shut down. A quick blow-torched screwdriver head inserted into the tip tapped the hole and everything started up and ran perfectly.

Anybody have a four red flash error code. Replaced the temperature limit switch. Not getting any codes,but the gas furnace still shuts off after a few minutes and. Thermostat shows desired temp five degree warmer than room

How do u open limit switch?