CIT - Certified Irrigation Technician System Maintenance and Repair Questions and Answers

Question 1

A technician performing a spring start-up on an irrigation system that has been properly winterized should perform which of the following steps FIRST to prevent system damage?

Accepted Answer

Ensure all drain valves are closed and then open the main shut-off valve very slowly.

Answer

The most critical first step when reintroducing water is to open the main valve slowly. This allows the pipes to fill gradually, preventing a sudden pressure surge known as water hammer, which can crack pipes, fittings, and other components. [3, 10]

Question 2

A pop-up spray head in a turf area fails to retract fully after the zone shuts off, creating a potential hazard. What is the most common reason for this issue?

Accepted Answer

Debris is wedged between the riser stem and the wiper seal or sprinkler body.

Answer

The most frequent cause for a pop-up sprinkler failing to retract is debris, such as sand, dirt, or grass clippings, becoming lodged between the movable riser and the stationary body or wiper seal. This friction prevents the retraction spring from pulling the riser down. [16, 21]

Question 3

A client reports an unusually high water bill. With all water off in the house and the irrigation controller off, a technician observes the small leak indicator dial on the water meter is spinning slowly. This indicates a leak in which part of the system?

Accepted Answer

The mainline between the water meter and the zone valves.

Answer

The mainline, the section of pipe between the water meter and the zone valves, is always under pressure. If the leak indicator on the meter moves when all fixtures and the irrigation system are turned off, it confirms a constant leak in this continuously pressurized section of pipe. [17, 18, 26]

Question 4

After a zone turns off, the sprinkler heads continue to weep or dribble a small but constant amount of water. The valve box itself is dry. What is the most likely cause of this problem?

Accepted Answer

A small piece of debris is preventing the valve's diaphragm from sealing completely.

Answer

A constant weep or leak through the heads when a zone is off is typically caused by a small particle of dirt, sand, or PVC shaving caught between the diaphragm and the valve seat. This prevents the diaphragm from creating a complete, watertight seal, allowing water to pass through. [27, 37, 39]

Question 5

When winterizing an irrigation system with PVC piping using an air compressor, what is the generally accepted maximum air pressure (PSI) to use to avoid damaging components?

Accepted Answer

40-80 PSI

Answer

Most industry guidelines recommend keeping the air pressure between 40 and 80 PSI for systems with rigid PVC pipes. Pressures exceeding 80 PSI can crack PVC fittings, damage valve internals, or break sprinkler heads. For polyethylene (poly) pipe, the maximum pressure should be even lower, around 50 PSI. [19, 20, 23]

CIT - Certified Irrigation Technician Practice Test

CIT - Certified Irrigation Technician Practice Test

CIT - Certified Irrigation Technician System Maintenance and Repair Questions and Answers