I have error codes flashing on my thermostat..it is an american standard model the manual for the therm. has ACOT900AC43UA on front..says to find addedum 18-HD32D2-1/69-2009 for codes i cannot find it anywhere..the error codes are 29 129 80 91

Error codes from American Standard Pub 18-HD32D2-8, which is a one-sheet document that came with my American Standard air-conditioner:

29 = not listed

129 = not listed

80 = HPCO Fault - problem is in outdoor unit - Desscription: High Pressure Monitor Fault (hard lock out, cycle power to reset)

91 = Communication Inactive Fault - problem is in air handler - Descriptions - COMM Bit Master Clock Error, COMM Heat/Cool Demand Error, Serial Motor Communication Inactive Error

91 = Communication Fault - problem is in furnace - Descriptions: Blower motor no COMM response, Inducer motor no COMM response, Loss of heat/cool demand, Loss of clock signal

91 = Communication Fault - problem is in outdoor unit - Descriptions: Loss of Heat/Cool Demand Message (COMM), Loss of Bit Master (Clock Signal)

91 = Communication Fault - Description: Comm line is dead and no bits have been received.

By the way, I do not recommend American Standard. I've had mine 14 months and it just blew up - the entire control panel blew. My advice to you - think about a different brand.

Nancy
Scottsdale, Arizona