I have a Lochinvar CH1800 hot water heating boiler that I've serviced for the past 6 yrs. I was onsite today on an unrelated mission when I noticed it was having a hard time igniting. Disassembled and pulled the burner panel out to inspect it. Of the 20 burners, 8 of them were totally incinerated, 4 were severely cracked, and 8 were okay (in the area of stgs 3 and 4). a similar meltdown occurred 2 yrs ago, with which I was involved in the repair and burner setup. The factory says that the burners are overfired. I just had those out 2 mos ago, and there no visible sign that any of these burners were getting too hot. Anybody ever had this problem ? The unit is an early 90's vintage.