Performed 1 system cooling diagnostics on a 20 plus year old AC/gas furnace. Customer stated that they had a power surge. I found that the transformer and furnace board. I also found that the capacitor for the blower motor is slightly outside of the manufacturer specifications and the gas line entering the furnace is not to code (flex gas line; needs to be cast iron). There maybe additional issues with the system; full diagnostics can’t be performed until transformer and board have been replaced. Customer declined the transformer and board repair and setup a time with an install supervisor to get an estimate to replace the hvac system.