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Plumber Interview Questions for freshers experienced :-
1. What is Pipe Dope?
A pipe dope is a pipe joint that is used to create a watertight seal.
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. Suppose I were to ask a previous supervisor about your performance, what would they say?
That I am enthusiastic and a good listener, Learner and a good plumber.
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. Have you ever changed a toilet before?
Yes, I have done this several times at college, and feel confident to do it independently.
6. 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.
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. 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. 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. 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. 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. What are the advantages for installing steel plumbing underneath a sink? In what cases would you do it?
The advantages to using steel would be more or less for industrial areas where chemicals will be used.
15. 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.
16. Do you know low Flush Toilet Problems?
You might buy a better flushing toilet for your situation. Some air assisted toilet flush well. When the low gallonage gravity toilets first came out I replaced a couple of new Kohler Wellworth Lites with the Am.Std. air assist toilet with good results. That was then and this is now. Today most brands of gravity toilets flush well (including the redesigned Kohler Wellworth models). Power assisted toilets tend to be noisy and frankly, today I definitely do not recommend power assisted toilets.
By the end of 1999 (most brands of U.S. made) gravity toilets manufactured were flushing fine. At the end of 2000 my guess is that over 85% of 1.6gpf toilets flushed well.
17. Do you prefer PVC or copper for piping?
PVC is definitely a better choice, since copper pipes tend to rust, heat up and are time taking to install in contrast to plastic piping that is easy to install, has greater insulation and is rust proof.
18. What is the worst thing you had to do as a plumber?
To me, there is no worst thing I’ve had to do. I’ve had a lot of dirty days as a plumber, but it is my job and to me there is no one job that was worse than any other job.
19. What do you enjoy most about being a plumber?
I enjoy making the customer happy, but what I enjoy the most is overcoming a challenging problem and fixing and correcting whatever the problem may be, its a great feeling.
20. What all tools are required to unclog a sink?
- Cup Plunger
- Duct tape or wash cloth
- Sink Auger
- Channeled type pliers
- Bucket
21. When I Run The CWM My Toilet Bubbles/Overflows or My Shower Overflows?
When the lowest plumbing fixture in the house overflows when another fixture (like a CWM) is draining; the septic tank needs to be pumped, there is a break in the sewer pipe outside the house or the main drain is plugged somewhere.
22. Do you own plumbing equipment?
Yes, I carry my own tool kit for basic tools.
23. Do you prefer your water mains be pvc or copper?
Pvc under the building and just inside the building then change to copper pretty much instantly with a stop tap.
24. 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
25. Do unused drains dry up and get rough inside?
Yes, drain pipes do dry out and get real rough. Will it clear up with use? Maybe.
26. Is there really a difference between hard water and soft?
Yes. In fact, the difference can be damaging to your home and your body. Maybe you have experienced damaged clothing from the laundry, excessive soap consumption, pipe scaling, faucet and fixture deterioration, skin problems, or undesirable tastes or odors from your water. If you have, then you have a water problem. Call Blue Mountain for expert advice on all kinds of water treatment systems.
27. 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.
28. How long has it been since you’ve had a leak with copper piping?
It honestly has been awhile. When I first learned to solder, I always had leaks, but as I did it more I got better and only on occasion would a copper pipe leak.
29. Explain me 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
30. How to 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
31. What is the most common reason for sump pump failure?
The leading cause for sump pump to failure is usually a switching problem. Sometimes the pump can move inside the basin. This movement causes the float that operates the switch to lodge against its side. Debris can also be a factor by interfering with the action of the pump switch. It is important to make sure that your pump switch and float arm assembly move freely. The main thing to remember about sump pumps is that they dont last forevereven if you never use them. Internal part wear out and make them virtually useless when you need them most! Blue Mountain can test, maintain or replace any brand of sump pump. For flood-prone areas and homes that get water seeping in on a regular basis you may want to consider a sump pump back up system. There are even non-electric systems that work in the case of a power failure. Call Blue Mountain for more information.
32. Please explain conventional Water Heaters vs. Tankless Water Heaters?
Conventional water heaters are by far the most common type of water heater in the U.S. today. They range in size from 20 to 80 gallons (or larger) and are fueled by electricity, natural gas, propane, or oil. Called torageunits, these water heaters transfer heat from a burner or coil to water in an insulated tank. The down side to a conventional water heater is that energy is consumed even when no hot water is being used.
Tankless water heaters do not contain a storage tank like conventional water heaters. A gas burner or electric element heats the water only when there is a demand for hot water.
There are many things to consider when choosing conventional vs. tankless water heating systems. Your Blue Mountain representative can guide you through your options and get the right system for home that will give years of service and efficient performance.
33. What is Gas HWT Height?
Gas HWT have to be at least 18″ off the floor because combustible fumes *sink* and for air intake.
34. Why did you leave your last job as Plumber?
Whatever the situation was from your previous job, you should always answer this question with a positive and enthusiastic response. If the reason for leaving your last job was redundancy, then you should talk about how your company had to restructure, instead of focusing on your own personal situation.
35. Explain me your salary requirements as Plumber?
Find out what the salary is for the job is that is possible ahead of time. If there is no salary posted then do some research. Find out what the market is paying and what you are worth. Make a reasonable salary offer based on this information. Do your best to avoid making a salary offer if you can. You can ask the employer if they have a salary range they plan to pay the person in this position.