The average hvac salary at Garland Isd was $45,038 , which is 19 percent lower than the average salary for this job in Texas, and 19 percent lower than the national average for this job . Hvac salaries at Garland Isd typically range from $33,249 to $56,452 (25th to 75th percentile). The highest reported hvac salary was $67,600. There are 12 employees at Garland Isd with the job title hvac.