I have a 2004 Carrier 58mvp 120 130btu 1HP Ecm motor, with a HK42FZ022 board. Every time there is a power bump the furnace defaults to high blower speed. The AC works but no heat, I then I have to remove the model plug, switch on sw1-6, run the test mode until code 11 flashes, slide dip switch sw1-6 back to off, replace the R wire and it works correctly, even with the model plug (PL4)removed. The blower is at the set slower speed and heat works. I have tested the model plug and resistors are OK and within spec! My way of thinking is when it is reset it works 100% turn the breaker/switch off and on BACK to the Code 25?
If this is a setup error, how do I reset the board? Could a solder joint on the board be the fault?
What I have been reading will the replacement board a HK42FZ024 solve the problem?
I have searched the internet up and down and I canít find anyone with a similar problem. HELP!