Lochinvar boiler shutting off

jms104

I have a 12 year old Lochinvar Solution boiler CBN180. It runs fine for a period of time and then stops heating. When I turn off the power switch, let it sit for a minute and then turn it back on it starts back up. It sometimes takes up to 12 seconds to light and I keep hearing the ignition attempts. Once it is back on it heats up quickly. Over the last month it has been turning off more frequently. First once a week, then daily and now sometimes it only runs 6-7 hours. I have had 2 different companies come out and look at it and they don’t know why this is happening. Any insight on what to do would be appreciated. Thanks.