While many people's experiences are different I can share mine. I went to school originally to be an electrician and got bored quickly as it was not mentally challenging. From there I took 2yrs college for plumbing,hvac. I graduated and started with my current employer the following Monday. You learn very quickly that the service sector is quite a but different as 24/7 service means someone is working 24/7. 18hrs on, 8hrs off during peak winter and summer is not unusual. This is not for many people. In the hiring sector I find that people that are use to a 9-5 job generally do not adjust well. While the entry level pay rate is low, you can demand to be paid what your worth. Install position has hours more stable but tend to be feast or famine depending on the season while service work is typically more steady. Overtime and double time makes up for the slow time. Some companies offer commissions on service agreement sales and can vastly supplement your Income. It is a career that will never go away! We will always be heating And cooling homes. Many other careers cannot have that security. Family can be difficult due to the uncertainty of hours. We had a customer 2 Fridays ago in a high end home that wanted a pool heater installed at 3pm. The closest unit was 1.5hrs away. NO PROBLEM. 2 installers and a delivery person worked till 930pm To get the customer taken care of. That is not a typical day but is expected. If I was to make a suggestion to a new person it would be to get hooked ip with a large company that will pay you to learn the trade. When I was hired the owner I the company told me "your job is to learn as much as you can so you can compete against me,,,my job is to make it so you do not want to" fast forward 17yrs and I am still there and plan on retiring there.