TEXAS MASTER PLUMBING ACTUAL EXAM 200 QUESTIONS & 100% CORRECT
ANSWERS (NEW UPDATED VERSION) LATEST ACTUAL EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED QUESTIONS AND ANSWERS) | GUARANTEED PASS A+ [2026]
Texas Master Plumber Practice Exam
1. What is the minimum water pressure required at a fixture for proper operation in a residential
plumbing system?
A) 15 psi
B) 20 psi
C) 30 psi
D) 50 psi
Rationale: Most codes require a minimum of 30 psi at fixtures to ensure proper flow and
operation.
2. According to the Texas Plumbing Code, what is the maximum distance a water closet can be
from its trap?
A) 12 inches
B) 18 inches
C) 24 inches
D) 36 inches
Rationale: Proper trap connection distances prevent leakage and maintain trap seal integrity.
3. A 3-inch horizontal drain line serves a group of sinks. According to standard drainage tables,
what is the maximum fixture unit load it can carry?
A) 24 DFUs
B) 32 DFUs
C) 40 DFUs
D) 48 DFUs
Rationale: Drainage Fixture Units (DFUs) determine pipe sizing; a 3-inch horizontal line
typically supports up to 32 DFUs.
2026 Graded A+ EXAM
, 4. Which type of vent is used to prevent siphoning of traps in a branch drainage system?
A) Circuit vent
B) Relief vent
C) Stack vent
D) Main vent
Rationale: Relief vents prevent negative pressure in the system that could siphon traps.
5. Copper tubing used for potable water distribution must be joined by:
A) Threaded connection
B) Soldered connection
C) Push-fit connection
D) All of the above
Rationale: Copper is commonly joined using solder (or brazing) for potable systems; threaded
and push-fit are options depending on code and application.
6. In sizing a gas pipe for a residential water heater, the pipe length is 20 feet, and the heater
requires 140,000 BTU/hr. What is the approximate nominal pipe size needed?
A) 1/2 inch
B) 3/4 inch
C) 1 inch
D) 1 1/4 inch
Rationale: Using gas pipe sizing charts, a 3/4-inch pipe supports up to ~140,000 BTU over 20
feet.
7. What is the minimum slope for a 2-inch horizontal drain pipe?
A) 1/4 inch per foot
B) 1/8 inch per foot
C) 1/2 inch per foot
D) 1 inch per foot
Rationale: Drainage slope ensures gravity flow; standard minimum slope is 1/4 inch per foot for
2-inch pipes.
2026 Graded A+ EXAM
ANSWERS (NEW UPDATED VERSION) LATEST ACTUAL EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED QUESTIONS AND ANSWERS) | GUARANTEED PASS A+ [2026]
Texas Master Plumber Practice Exam
1. What is the minimum water pressure required at a fixture for proper operation in a residential
plumbing system?
A) 15 psi
B) 20 psi
C) 30 psi
D) 50 psi
Rationale: Most codes require a minimum of 30 psi at fixtures to ensure proper flow and
operation.
2. According to the Texas Plumbing Code, what is the maximum distance a water closet can be
from its trap?
A) 12 inches
B) 18 inches
C) 24 inches
D) 36 inches
Rationale: Proper trap connection distances prevent leakage and maintain trap seal integrity.
3. A 3-inch horizontal drain line serves a group of sinks. According to standard drainage tables,
what is the maximum fixture unit load it can carry?
A) 24 DFUs
B) 32 DFUs
C) 40 DFUs
D) 48 DFUs
Rationale: Drainage Fixture Units (DFUs) determine pipe sizing; a 3-inch horizontal line
typically supports up to 32 DFUs.
2026 Graded A+ EXAM
, 4. Which type of vent is used to prevent siphoning of traps in a branch drainage system?
A) Circuit vent
B) Relief vent
C) Stack vent
D) Main vent
Rationale: Relief vents prevent negative pressure in the system that could siphon traps.
5. Copper tubing used for potable water distribution must be joined by:
A) Threaded connection
B) Soldered connection
C) Push-fit connection
D) All of the above
Rationale: Copper is commonly joined using solder (or brazing) for potable systems; threaded
and push-fit are options depending on code and application.
6. In sizing a gas pipe for a residential water heater, the pipe length is 20 feet, and the heater
requires 140,000 BTU/hr. What is the approximate nominal pipe size needed?
A) 1/2 inch
B) 3/4 inch
C) 1 inch
D) 1 1/4 inch
Rationale: Using gas pipe sizing charts, a 3/4-inch pipe supports up to ~140,000 BTU over 20
feet.
7. What is the minimum slope for a 2-inch horizontal drain pipe?
A) 1/4 inch per foot
B) 1/8 inch per foot
C) 1/2 inch per foot
D) 1 inch per foot
Rationale: Drainage slope ensures gravity flow; standard minimum slope is 1/4 inch per foot for
2-inch pipes.
2026 Graded A+ EXAM
