Replaced circuit board due to the phantom errors unit was having. I asked customer if it had ever locked out and was blinking red and no heat she explained no but every time she had turned her thermostat off there would be a wrench on the screen ther errors listed were all the same sp1 first ignition failure. I’ve tested co #s with combustion analyzer and all within range per manufacturer recommendation. Once board was replaced set up all parameters per manufacturer specs when replacing the board. We tested the unit and operation of the system is normal. No charge warranty
