Top 15 Plumber interview questions & Answers

1) Explain what is the primary step to unclog any blockage in the pipes?

First and primary technique to unclog the blockage is to pour hot water through the pipes. If the blockage still remains then, you need to use other options.

2) What is referred as Building Drain?

The lowest point in a drainage system where the interior drainage pipe meet and are conveyed into the sewer is referred as Building Drain.

3) List out some of the most common tools required for plumbing?

• Adjustable pipe wrench
• Faucet valve seat wrench
• Faucet valve reseating tool
• Faucet packing and washers
• Tubing cutter
• Teflon tape
• Cup plunger
• Flange plunger
• Closet Auger
• Sink Auger

4) What skills does a plumber should have?

• Problem solving
• Critical thinking
• Listening and paying attention to instruction
• Decision making
• Co-coordinating
• Technical knowledge related to pipe fitting

5) What all tools are required to unclog a sink?

• Cup Plunger
• Duct tape or wash cloth
• Sink Auger
• Channeled type pliers
• Bucket

Plumber

6) Mention what are the different types of chemical drain cleaners are used?

• Caustic drain cleaners: It contains a substance like caustic potash; they are bases and give electron to the clogging substance. This reaction will generate a lot of heat and dissolves the clogging substance, and clears the blockage.
• Oxidizing drain cleaners: It contains chemicals like household bleach, peroxides and nitrates. These chemical cause the organic material of the clog to lose an electron and become oxidized. It also generates heat and gas, which clears the blockage.
• Acid drain cleaners: It contains a higher concentration of acid and the hydronium ions present in acid reacts with clogging substance and releases heat. This heat will dissolve the substance and clears the blockage.

7) What is the home remedies to clear clogged drain?

The home remedies to clear clogged drain is

• Take half a cup of baking soda and pour down the drain, and then pour half a cup of vinegar. After 15 minutes, flush out the drain with hot water
• Add equal parts of salt, vinegar and baking soda. After one hour pour hot water into it
• Add half a cup of salt and equal amount of baking soda, sprinkle it into the drain and then flush it with hot water

8) Explain what is Angle Stop?

Angle stop is a shutoff valve between the water supply pipe and the fixture it supplies. It is used to shut off water to a fixture in case of failure, repair or leakage.

9) Mention what are some health and safety issues that plumber face?

Some of the health and safety risk that plumber face are

• Exposure to a hazardous substance like lead, sulfur dioxide, mould, carcinogenic substances
• Exposure to flammable and combustible materials
• Working in awkward positions may lead to musculoskeletal injuries
• Lifting heavy or awkward objects
• Risk of eye injury from flying particles
• Burns from hot equipment’s like steam lines, hot water heater, etc.
• Cut and bruises due to a sharp end of pipes
• Risk of electric shock while digging under-ground water pipes

10) What pre-caution a plumber could take for health and safety purpose?

• Avoid awkward body positions, and take break every 30 minutes
• Learn safe lifting techniques
• Wear appropriate footwear and gloves while handling sewage plant or metal pipes
• Keep tools and equipment’s in working condition, to avoid any unexpected accident due to inoperative tools
• To avoid electric shock use only power tools that can be used in a wet environment and have GFCI (Ground fault circuit interrupter).
• Keep work area clear

11) Explain what is the common reason for sump pump failure?

Sump pump is usually used in the basement area to remove the accumulated water during flood. Moreover, there are few reason it may stop working all of sudden.

• Switching problem
• Accumulation of excess debris, interfering with the switching
• The pump can move inside the basin, and that may interfere with the switching mechanism

12) Explain how you can fix a leaky PVC water pipe?

• Drain the water out and make the leakage pipe dry
• Now take a coupling, similar to the size of the pipe that is leaking
• Now cut the coupling into half
• Make sure that the half you going to use should have stop inside, as you have to slide the leakage pipe into it
• Slather the inside of the patch with adhesive, make sure that you have enough of the adhesive on your patch, as that is the portion that going to connect with the leaked pipe.
• Place the patch onto the pipe and slide it into place and keep it overnight to get dry

13) How can you avoid bathroom plumbing maintenance?

To avoid bathroom plumbing maintenance you can use the following tips

• Once a week flushes out the drainage pipes with hot water
• Apply pipe shield to drain lines once each month to keep soap scum building up and causing clogs
• To prevent further damage to the fixtures and faucets repair leaky faucets
• Showers and tubs should be fitted with strainers that can catch hair and soap chips
• Use vinegar to remove mineral deposit in your shower head, by placing a vinegar in a plastic bag and leave it over the shower head overnight. Take only 1 cup of vinegar.
• Throw the waste in wastebasket like tissue paper, cotton ball, etc.

14) Explain what is Pipe Dope?

A pipe dope is a pipe joint that is used to create a watertight seal.

15) Explain what is Eductor?

Eductor is a device that utilizes a nozzle and throat, fitted in a stream of water to build a partial vacuum to draw liquid or air into the stream; normally used to draw regeneration chemicals into an ion exchange water treatment system, like deionizer or softener.

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  1. Avatar
    Douglas says:

    very refreshing

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  2. Avatar
    GOWTHAM says:

    I WANT MORE & more gk fully deeply

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  3. Avatar
    Chitta Ranjan Barik says:

    I am chitta Ranjan Barik… Good job plumbing

    Reply
  4. Avatar
    Onesimo HolweniOn says:

    Im nevourse tomorrow ihave interview for plumbing aprentice but i learn more here thank you

    Reply