The average hvac salary at Frisco Isd was $42,427 , which is 24 percent lower than the average salary for this job in Texas, and 24 percent lower than the national average for this job . Hvac salaries at Frisco Isd typically range from $33,354 to $50,559 (25th to 75th percentile). The highest reported hvac salary was $79,384. There are 14 employees at Frisco Isd with the job title hvac.