I have a Trane XB80, 8 years old. All was well for a week and it just happened again! The thermostat goes blank, does not show any numerals. I touch the black switch in the lower part of the furnace and the furnace kicks on, gas flows, thermostat shows the temperature. House is well heated. Worked well for a week and then same thing happened overnight. What is the cause? What should I do to fix this? Thank you

What trane tstat?

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Had error code 91 on Trane XL19i thermostat. Heat season on duel fuel system. Repair tech said board is bad ($963) and transducer ($1000). Unit is 3 ton 12 years old. Does it make sense to repair or put in a new unit?

If the unit is running in cold weather than there is ice building up on the coils located outside. This is normal in that the unit is running in heat pump mode heating inside and cooling outside, After the unit detects the ice build up it briefly reverses the cycle heating the outside coils melting(defrosting) the ice which you observe as water on the pad.

The video gives you an example of the defrost cycle!
2012 Trane XL15i Heat Pump Defrost Cycle Steam Show

replace the thermistat module..sounds like it has a bug in the firmware

You probably have it running a program. Try using it simply on heat mode. Then set temperature and press hold on thermostat. The word hold should show up on the screen.

You will either have a fault with the inverter board which drives the backlights or a faulty backlight in the screen. If the problem is a backlight then a replacement screen is the only cure. One or the other is breaking down after it has been opn for a certain period of time, have an engineer call out & check with a tester if it is a screen problem.

nope, nope, sounds like a stuck contactor in the electrical compartment of the condenser, but there are actually several things that could cause it.

try replacing the batteries in the thermostat on your wall. probably has 2 AA's this may fix it if not may have bad or old wiring from tstat to main indoor system. when you had a trane installed did they change the air condition components only(likely) or did they put in new furnace, new wiring, new t-stat, a full install?

use the outside designations for heat pump, and inside for standard, I would assume a heat pump since you have more than five wires attached to it now. Use the colors of the wire to match to the designations, use tan for y2, black for w2 rc and rh should already have a factory jumper. I would have to trace out the "U" and see where it terminates, I have not seen a bare wire on a stat in 27 years of doing this. before powering, verify the tan and black at the indoor unit circuit board and see if they are landed on the terminals designated at the stat. hope this helps

The Chrono Therm 3 and 4's were some of the worst products that honeywell has EVER put out. I would suggest switching to the Vision Pro 8000, please consult your local HVAC company for more information regarding the change over.

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