On October 13, 2021 I arrive to a Blue Shield customer for a full tuneup upon arrival I agree to the customer I then went to the thermostat can you turn the system to heat and turned it up customer stated that the back light on the thermostat flashes when you touch the button and then goes right back off pour off the wall ask the customer for some batteries install the batteries to see if that will change anything on the thermostat and the back light stayed on when the button was pushed until it shut off like it supposed to I then went to the furnace did Did amp drawls on the blower motor I did amp drawls on the inducer motor pool and clean the flame sensor did amp draw on the hot surface igniter and check the gas pressure it was at 3.8 I regulated down to 3.3 everything is working properly at this time thank you for your business Mike T