Not to sound rude, but you should have a left your company 10 years ago. Also, If you are working in Building systems/MEP then you should not have waited 15 years to get your PE. MEP is all about the PE!
Keep looking and be persistent. Make your LinkedIn profile pop out to recruiters. I was not thrilled with the salary grown I was getting compared to my responsibility/experience growth. I polished up my LinkedIn account and clicked that little "Looking" button. Two months later I had completed a few awesome interviews and found myself accepting a job with a 40% salary increase, amazing benefits, and a great work environment.