That is a tough situation to be in. And way too common now in our great USA. I'm now retired from the fed. govt. I still enjoy working hard, but I just don't understand the decline of work ethic. I could digress now, but I won't.
Off the top of my head, here's a couple suggestions.

1) Hire retired HVAC techs for 1 or 2 days a week. There are some retirees who still want to work some, but can't handle 40 hrs a week.

2) Go to your local or private school system and offer to assist in starting an apprentice program