DL2 exploded

Have you had a lamp actually explode in the projector?
If so there is a good chance that there is debris inside still (like a small piece of broken glass) that might be getting caught in one of the projector's fans.
If this is the case you should either swap the actual projector out (LX50 or LX55 depending on your unit) to have the problematic one serviced professionally, or swap the whole DL.2 unit out for the same reasons.

Overall, to me it sounds like an airflow problem.
What type of "air dome" is the unit mounted in?
You may have temperature and/or airflow issues if there is not enough airflow getting to the unit.
You may want to see what the average and peak operating temperatures are inside the "dome".
90% humidity is not great for any piece of mechanical and/or electronic equipment either.
Is the "dome" equipped with anything to filter out humidity?

Hope this helps. :)

Have you had a lamp actually explode in the projector?
If so there is a good chance that there is debris inside still (like a small piece of broken glass) that might be getting caught in one of the projector's fans.
If this is the case you should either swap the actual projector out (LX50 or LX55 depending on your unit) to have the problematic one serviced professionally, or swap the whole DL.2 unit out for the same reasons.

Overall, to me it sounds like an airflow problem.
What type of "air dome" is the unit mounted in?
You may have temperature and/or airflow issues if there is not enough airflow getting to the unit.
You may want to see what the average and peak operating temperatures are inside the "dome".
90% humidity is not great for any piece of mechanical and/or electronic equipment either.
Is the "dome" equipped with anything to filter out humidity?

Hope this helps. :)