I have about 8 yr old raypack LP spa/pool heater ( 266a) and about 6 months ago wouldn't light one rainy night and had code ILO. The next day when it was daylight functioned fine and worked many times. Then about two weeks ago if had same error and I could troubleshoot better. Both times was rainy night. ( I love to drink beer in the spa in the rain). The pilot was lighting and on and still locked out ignition with ILO code. Next day fired right up at least dozen times. I took main control board out, cleaned all connections and looked for loose grounds because interior of unit has some corrosion. Functioned fine before and after my "fix". Last night tried to use spa and had new error, CLK. This is odd because pool had been off for a bit when I started it all up to use spa so no idea why it would have clock error. Today when I went to work on it this morning and worked fine, lite fine at least 10 times. Intermittent things are tough. What is opinion of the pros? Board failing? Thanks in advance.