You're never too old. Most employers will appreciate a mature person. You're making me feel old, 32!
The HRSDC Website (http://www.jobbank.gc.ca/LMI_report_area.do?&area=9219&reportOption=wage) lists Refrigeration and Air Conditioning Mechanic wages between $30 and $45 in the Toronto area. A union company would probably pay the highest wages.
The College of Trades Apprenticeship Training Standard (http://www.collegeoftrades.ca/wp-content/uploads/Refrigeration-and-Air-Conditioning-Mechanic-313A-EN-TS3.pdf) states,
QuoteWages
5. (1) The rate of wages for an apprentice who is working in an apprentice training program to become a refrigeration and air conditioning systems mechanic shall be no less than the following percentage of the average rate of wages for journeypersons who have received such a certificate and are employed by the employer with whom the apprentice is working:
1. 40 percent, during the first of the five periods of apprenticeship referred to in subsection 4(1).
2. 50 percent, during the second of the five periods of apprenticeship referred to in subsection 4(1).
3. 60 percent, during the third of the five periods of apprenticeship referred to in subsection 4(1).
4. 70 percent, during the fourth of the five periods of apprenticeship referred to in subsection 4(1).
5. 80 percent, during the fifth of the five periods of apprenticeship referred to in subsection 4(1).
(2) The rate of wages for an apprentice who is working in an apprentice training program to become a residential air conditioning systems mechanic shall be no less than the following percentage of the average rate of wages for journeypersons who have received such a certificate and are employed by the employer with whom the apprentice is working:
1. 40 percent, during the first of the two periods of apprenticeship referred to in paragraph 1 of subsection4(2).
2. 60 percent, during the second of the two periods of apprenticeship referred to in paragraph 1 of sub section 4(2).
3. 80 percent, during the period of apprenticeship referred to in paragraph 2 of subsection 4(2).
(3) Despite subsection (1), if a person holds a certificate of qualification as a residential air conditioning systems mechanic and begins an apprentice training program described in subsection 4 (3), the rate of wages for the person during his or her apprenticeship shall be no less than the following percentage of the average hourly rate of wages for journeypersons who have received such a certificate and are employed by the employer with whom the apprentice is working:
1. 60 percent, during the period of apprenticeship referred to in paragraph 1 of subsection 4(3).
2. 70 percent, during the first of the two periods of apprenticeship referred to in paragraph 2 of subsection 4(3).
3. 80 percent, during the second of the two periods of apprenticeship referred to in paragraph 2 of subsection 4(3).
(4) The minimum rate of wages established under subsections(1),(2) and (3) apply to all of the apprentice's hours of work, whether for regular daily hours of work or for hours of work in excess of the regular daily hours of work.
Are you interested in doing gas work as well? It sounds like you want to do commercial work, so for refrigeration you need the 313A certificate and for gas the G1 certificate.
Some workers only do installations and work fairly regular hours. A service technician would be on call and working afterhours, on top of their regular weekly hours. Shifts vary from company to company, but it's usually always 24/7 service.
It might be difficult to get hired on as a 1st year apprentice. You may have a better chance of getting into a HVAC company as a laborer. As you complete schooling and gain work experience, you could look at challenging the exams.
Visit local HVAC wholesaler and look for job postings. Call all the companies you can and drop off resumes.
The first few years can be rough, but it will pay off if you stick with it. It can be a very rewarding career.
Good Luck!