Principles of Installation practice

All 12 free principles of installation questions

1. Where the maker gives no depth figure, irrigation pipe needs a minimum cover of:

   • A 2 in Two inches is the reduced cover allowed only where a utility, a structure or roots make the 6 inch cover impractical.
   • B 6 in Correct
   • C 12 in The state minimum is 6 inches of select backfill; no 12 inch cover is set for irrigation pipe.
   • D 18 in The state minimum is 6 inches of select backfill; no 18 inch cover is set for irrigation pipe.

   Where the manufacturer publishes no depth coverage figure, piping must have at least 6 inches of select backfill between the top of the topmost pipe and the natural grade (30 TAC 344.62(l)(1)). The 2 inch figure applies only where a utility, a structure or roots make the 6 inch cover impractical (30 TAC 344.62(l)(2)).

   30 TAC 344.62(l)(1) and (l)(2)

2. On a new system, the isolation valve is installed:

   • A Between the meter and the backflow device Correct
   • B Downstream of the master valve The master valve sits downstream of the backflow assembly; the isolation valve belongs upstream of the assembly, after the meter.
   • C At each zone valve Zone valves control single zones; the rule places the isolation valve between the meter and the backflow assembly.
   • D Upstream of the water meter The rule puts the isolation valve after the meter, between it and the backflow assembly, not ahead of the meter.

   Every new irrigation system must include an isolation valve between the water meter and the backflow prevention assembly, so the valve sits after the meter and ahead of the assembly (30 TAC 344.62(k)).

   30 TAC 344.62(k)

3. Which valve turns a single zone on and off?

   • A The master valve A master valve controls the flow of water to the whole mainline, not one zone.
   • B The isolation valve An isolation valve shuts off the supply between the meter and the backflow assembly; it does not run a zone.
   • C The zone valve Correct
   • D The quick coupler valve A quick coupler valve gives hose or key access to water; it does not switch a zone on and off.

   A zone valve is the automatic valve that controls only a single zone of the system. A master valve controls flow to the whole mainline instead (30 TAC 344.1(47)).

   30 TAC 344.1(47)

4. According to TCEQ, where does a master valve go when one is installed on a new system?

   • A Upstream of the backflow device The rule puts the master valve on the discharge side of the backflow assembly, which is downstream, not upstream.
   • B Downstream of the backflow device Correct
   • C Between the meter and the isolation valve The space between the meter and the backflow assembly is where the isolation valve goes, not the master valve.
   • D At the end of the last zone The master valve controls the mainline after the backflow assembly; it is not placed at the end of a zone run.

   When a new installation has a master valve, it must go on the discharge side of the backflow prevention assembly. A master valve is optional, and the placement rule applies only when one is provided (30 TAC 344.62(h)).

   30 TAC 344.62(h)

5. What voltage do most valve control wires carry?

   • A 24 volts AC Correct
   • B 12 volts DC The usual valve circuit runs on alternating current at about 24 volts, not 12 volts DC.
   • C 110 volts AC The valve wires carry low voltage; 110 volts is not the usual valve circuit.
   • D 220 volts AC The valve wires carry low voltage; 220 volts is not the usual valve circuit.

   The circuit from the controller out to the valves is a low-voltage circuit, and the current it sends to energize each solenoid is usually 24 volts AC. That means 110 and 220 volt figures are not the valve wire circuit.

6. How long must an irrigator keep installation records?

   • A 6 months The rule sets three years from completion; six months is far short of it.
   • B 1 year The rule sets three years from completion, not one year.
   • C 2 years The rule sets three years from completion, not two years.
   • D 3 years Correct

   An irrigator must keep records for three years from the date the installation, maintenance, alteration, repair or service was completed (30 TAC 344.38).

   30 TAC 344.38

7. How many hours of approved training does an irrigator need to renew the license?

   • A 8 hours No license in this group renews on 8 hours; the irrigator figure is 24.
   • B 16 hours Sixteen hours is the irrigation technician renewal figure, not the irrigator figure.
   • C 24 hours Correct
   • D 32 hours The rule sets 24 hours for an irrigator, not 32.

   Renewing an irrigator license requires 24 hours of approved training credits on top of the general renewal requirements. The 16 hour figure applies only to an irrigation technician license (30 TAC 30.122(b)).

   30 TAC 30.122(b)

8. How many members sit on the Irrigator Advisory Council?

   • A 7 members The council has nine members, not seven.
   • B 9 members Correct
   • C 11 members The council has nine members, not eleven.
   • D 12 members The council has nine members, not twelve.

   The Irrigator Advisory Council has nine members, a number the rule sets, all appointed by the Texas Commission on Environmental Quality (TCEQ): six must be licensed irrigators and three represent the public (30 TAC 344.80(a) to (c)).

   30 TAC 344.80(a)

9. A licensed irrigation technician works under the supervision of:

   • A A licensed irrigator Correct
   • B An irrigation inspector An inspector enforces local rules and checks the work; he does not supervise the technician.
   • C A backflow tester A backflow tester tests assemblies; the rule gives supervision of a technician to a licensed irrigator.
   • D The property owner The owner is the customer; the rule requires a licensed irrigator to supervise the technician.

   An irrigation technician installs, maintains, alters, repairs or services systems only under the supervision of a licensed irrigator (30 TAC 344.30(b)(2)).

   30 TAC 344.30(b)(2)

10. What is a group of zone valves installed together in one spot called?

    • A A header A header is a pipe feeding several outlets, not a grouping of control valves.
    • B A loop A loop is a pipe layout that feeds from both ends, not a grouping of control valves.
    • C A manifold Correct
    • D A swing joint A swing joint connects a head to a lateral; it has nothing to do with grouping valves.

    A manifold means control valves grouped side by side in one area rather than spread across the site. A header, a loop and a swing joint are piping terms, not a valve grouping.

11. Who may approve a change from the irrigation plan during installation?

    • A The irrigation technician The rule gives the power to authorize plan changes to the licensed irrigator, not the technician.
    • B The licensed irrigator Correct
    • C The property owner The owner may ask for a change, but the rule gives the authorization to the licensed irrigator.
    • D The city inspector The inspector checks the work; the rule gives the authorization to the licensed irrigator.

    During installation the licensed irrigator authorizes changes from the original plan, and each change must be documented in red ink on the plan. The change also must not weaken the system or break a rule (30 TAC 344.61(d)).

    30 TAC 344.61(d)

12. Why is PVC pipe laid in a slight snake pattern in the trench?

    • A To allow for expansion and contraction Correct
    • B To lower friction loss in the line Extra bends add length, so snaking does not lower friction loss.
    • C To raise the water velocity Snaking the pipe does nothing to raise velocity; its purpose is movement with temperature.
    • D To keep the control wire centered The guide lays wire beside the pipe; snaking the pipe is for expansion and contraction.

    Laying the pipe in a serpentine pattern before backfilling leaves slack so that the pipe can expand and contract in the trench.

    UFGS 32 84 23, Underground Sprinklers, p. 20 Reference document, not law.