What do you call someone who works on sprinklers?

Someone who works on sprinklers is called irrigation technician, irrigation specialist, sprinkler installer, sprinkler repair technician, or irrigation contractor. In professional context, person who designs and installs irrigation systems is called irrigation contractor or irrigation installer, often licensed. Person who repairs and maintains systems is called irrigation technician or sprinkler repair technician. In landscaping company, they may be called irrigation tech or lawn irrigation specialist. For large scale agriculture, person may be called irrigation engineer who designs complex systems. If they work specifically on fire sprinklers, they are called fire sprinkler fitter or fire protection technician, different from lawn irrigation. So common terms are irrigation technician for maintenance and repair, irrigation contractor for installation, and sprinkler fitter for fire systems. Many states require certification like Certified Irrigation Technician from Irrigation Association for professionals who work on sprinklers, ensuring knowledge of water management and system design.