What does it mean when a faucet is said to have 8-inch centers?

The faucet mounts with the fixture holes set 8 inches apart. It’s important that you buy the right size faucet to fit.

What is plumber’s putty?

It is a sealing putty used for a variety of tasks including to seal basket strainers, garbage disposal rims and tub drains.

I don’t have enough room under my sink to get the faucet nut off.

A basin wrench is a tool designed especially for that.

What is the purpose of pipe joint compound or tape?

They reduce friction in assembly and provide a watertight seal.

Which is better for sealing – Teflon(TM) tape or thread joint compound?

They do the same job, but Teflon(TM) tape is easier to work with and makes a cleaner joint.

What kind of solder do I use on a water line?

Health codes require lead-free solder.

Do you recommend plastic pipe cleaners and primers?

These are applied to a pipe and fitting before applying the solvent weld glue to ensure a strong bond. Their use is always a good idea, especially if it’s for a water supply line or the connection is going to be somewhere that will be difficult to get to in the future.

What does flux do?

It cleans the surface prior to soldering. It prevents the oxidation of the metal. And it allows the solder to flow freely.

Is there a wrench I can use that will not damage the brass, aluminum or other soft material?

Yes, a strap wrench grips the pipe without teeth.

What is the difference between PVC and CPVC plastic pipe?

CPVC can be used on hot and cold lines, while PVC is for cold water only. PVC is usually used as a drainpipe.

How should I cut plastic pipe?

Any fine-tooth saw will work, but make sure you remove any burrs.

What is the proper way to join galvanized pipe to copper pipe?

You should use a dielectric union. This will prevent electrolysis from occurring, which deteriorates the copper tubing.

Is 1/2″ CPVC and 1/2″ PVC the same size?

No. CPVC is measured by O.D., which makes its sizing similar to hard copper. PVC is measured by I.D., which makes its sizing similar to iron pipe.I am not getting enough hot water from my gas water heater.The thermostat may be set too low, otherwise the burner is probably not burning correctly. If that’s the case, it’s best to call a service technician.

Are all electric hot water heater elements the same?

There are three types: screw in, bolt in and clamp in. They all have different wattage ratings and can work on either 120 or 240 voltage.

There is water leaking from my water heater. What’s the cause?

The pressure relief valve could be leaking. Try operating the valve to see if it will stop. It also might need tightening. A gasket around the heating element may need to be replaced, or the tank could be rusted out, which requires a new hot water heater.

What size water heater should I buy?

Most people base their purchases on the size of the storage tank, but a better method is to first estimate how much hot water you will need during the peak hour of use. This is referred to as the first-hour rating (FHR) on the Energy Guide label posted on new water heaters. Typical hot water use is:

  • Showering 3 gallons/minute
  • Bathing 15-25 gallons per bath
  • Shaving 1-3 gallons
  • Washing hands 1/2-2 gallons
  • Washing dishes 4-6 gallons
  • Running dishwasher 5-20 gallons
  • Running clothes washer 25-40 gallons
  • Cleaning house 5-12 gallons
  • Food preparation 1-6 gallons

What is the purpose of a pressure relief valve on a water heater?

This is a safety device that will open in case of high pressure or temperature.

What diameter trap do I need for my kitchen sink?

These are almost always 1-1/2 inches. The 1-1/4 inch traps are for bathroom lavatories.

What is the correct size of garbage disposal that I should put under my sink?

If you are replacing an existing unit that has worked well for a number of years, the old size should work fine. Otherwise, 1/3 horsepower will handle limited use once a day. A standard 1/2 horsepower will normally suffice for general use. Heavy-duty 1/2 horsepower units and larger are designed for a large volume of garbage.

What are the working parts of a toilet?

The refill valve, the flush valve and the trip lever.

How do I replace a damaged refill valve?

Turn off the toilet’s water supply valve, flush the toilet and sponge out any remaining water in the tank. The refill valve is usually removed by turning a nut that holds it in place. When the nut is off, the refill assembly can be lifted out. Install the new assembly by following the manufacturer’s directions.

You stock two sizes of supply lines. Which one will I need for my toilet?

The toilet supply line head is the larger of the two. The smaller ones are sink supply lines.

My toilet fills up every 10 minutes. What is the problem?

If the toilet flushes on its own, the flush valve is probably not seating properly and water is leaking from the tank into the bowl. This could be the result of the lift chain being tangled. If it is the valve, you can change the flapper. Scale deposits on the seat can be removed with steel wool or with No. 500 abrasive paper. Make sure you clean the valve seat. If it still leaks, the seat is damaged and you will need to replace it as well.

What does O.D. and I.D. mean?

This refers to the diameter of a pipe. Some pipes are measured based on their outside diameter, or O.D. Others are measured by their interior diameter, or I.D.

What do I need to do to repair my leaking faucet? Is it leaking from the handle or out the spout?

Most faucets are washer-type, and if these are leaking from the spout, you will have to replace the washer. If the seat is corroded, you will have to dress it or replace it.

If it is leaking from the handle, you may need to replace the O-rings, tighten the packing nut or replace the packing.

If a disk faucet is leaking, you will need to replace the O-ring. If it is leaking from the spout, you will need to replace the disk assembly. For ball-type faucet leaks, you may need to replace the cam assembly, the seat assembly and the ball.

Are all faucet seats the same?

No, you will need to bring in their old seat to match up with the new one. Each brand has its own design and thread.

How do I remove the seat?

Use a seat wrench, which has several sizes of square and hex ends.

What are the advantages of plastic supply lines?

They are less expensive, do not corrode, will not kink, are more flexible and are non-toxic.

My sump pump runs constantly. Do I need to buy a new one?

It could just be a bad switch that is easy to replace.

I just refinished my basement and I want to ensure that it doesn’t flood. Do you have any advice?

You can buy a sump pump that has a battery back up. There are also high-water alarms.

Do I use the same type of glue for both PVC and CPVC?

No, CPVC requires special solvent cement that is different from cement used for other types of plastic pipe.

How do I join fittings to plastic pipe?

Use a solvent welding glue, which softens the pipe and fittings so they can melt together.

Can the fittings be removed after they have been glued?

No, they are permanently joined and cannot be taken apart.

What do the letters “K,” “L” and “M” on copper tubing mean?

Type K is the heaviest. Type L is medium weight and used most often for water lines in homes. Type M is thinner and is used underground or for light domestic water lines if local codes allow.

I am getting no hot water from my electric water heater.

The high-temperature cutoff may have been tripped, which requires someone to press the reset. Otherwise it’s probably a faulty heating element or thermostat, which can be replaced.

I’m not getting enough hot water from my electric water heater.

The temperature control may be set too low. Otherwise it’s probably a faulty heating element or thermostat, which can be replaced.

The water from my electric hot water tank is too hot.

The thermostat may be set too high, or it may be faulty. It could also be a grounded heating element.

I am getting no hot water from my gas water heater.

The pilot light might be out, or you may have a faulty thermostat.

Is there any maintenance for a water heater?

Yes, you should test the pressure relief valve regularly and replace it if it fails to operate. At least once a year you should flush out the sediments. As long as a tank has a functioning anode, it should not rust. Therefore you should check the anode about once every two years. The fitting is usually on the top of the tank and it’s often tight, so a torque multiplier is a useful tool. If you find 6″ or more of the steel core wire exposed, or if the rod formed a hard, adherent calcium carbonate coating that prevents further corrosion of the sacrificial metal, replace the rod. There are segmented rods if overhead clearance is limited.

I think my kitchen drains are partially clogged because the sink drains slowly. What do you recommend?

First, try using a plunger. Second, try using a liquid drain opener, but use caution and read directions. Third, you can remove the trap. Be careful if you have used a liquid drain opener because there may be some in the trap. Fourth, if the clog is beyond the trap, there are drain augers that extend from about 15′ to about 50′.

Do you have anything I can put in my drain line that will kill the tree roots invading the line?

There are root killers that contain copper sulfate.

What is the purpose of an aerator on a faucet?

An aerator diffuses the water to prevent splashing.

Is a trap necessary under the sink?

You need a trap to shut off odor (sewer gas) from coming into the kitchen and bath area.

Can I use plastic drain parts on metal drain parts under the sink?


In the long run, which is better – chrome drain parts or plastic?

Plastic will usually last much longer than chrome, but you have to be careful because it can be affected by some harsh chemicals in drain cleaners.

What is a check valve?

A check valve keeps water from returning to the sump pit or crawl space after the pump shuts off.

What is the difference between soft copper tubing and hard copper tubing?

Hard copper is rigid line used throughout the house. Soft copper is used where flexibility is needed, such as faucet supply lines.

What is a compression fitting?

This type of fitting squeezes a brass or plastic ring around copper or plastic tubing.

What is a flare fitting?

A connector is slipped over the end of a copper tube, which is then flared out using a special tool. The fitting can then be screwed into another fitting.

Can I solder soft copper?


How do I solder copper tubing?

Clean the inside of the fitting, clean the outside of the tubing, apply acid flux, heat the fitting and apply the solder.

Can I attach metal fittings and plastic fittings?

Yes, there are transition fittings that make this possible.

There is water seeping from around the base of my toilet. What do I need to do to solve this problem?

Your wax gasket is probably not working anymore. This is a simple problem to fix. You need to remove the toilet and install a new wax ring. While you have the toilet off, you should go ahead and replace the bolts. Otherwise, it could be a crack in your toilet bowl.

What do I do if there is a crack in the bowl?

If it is a small crack, you can try to repair it. Drain the toilet, dry it off, apply some Plumber’s Goop and let it dry completely before refilling the tank. However, you may have to replace the bowl.

The toilet bowl is not filling up. What is the problem?

See if your toilet has an overflow pipe. If so, a rubber tube should go into it. It has a metal clip on it and sometimes it can come loose.

When replacing a faucet, I was told that I should put some putty underneath the faucet. Why?

This is a good idea to keep moisture from getting under the faucet and into the cabinet below.

I have a problem with the plumbing in my house making groaning and honking sounds.

It could be that you have lost your “air cushion.” To get it back, turn the water supply off at the main valve. Turn on all the faucets around your home. Then turn on the main valve again and shut off each faucet. This should take care of the problem.

What is a supply valve?

This valve is under the sink or beside the toilet and shuts off the water to the faucet or toilet.

Is there an easy way to replace the seat?

There are glue-in repair kits, but not all kits fit all toilets. And you must follow the manufacturer’s directions closely.

How do I replace the seat?

The flush valves are held to the tank by one large jam nut on the bottom of the tank. Installing a new valve usually requires removing the tank from the bowl.

How do I test to see if water is leaking from the tank into the bowl?

After flushing the toilet, let it refill. Now put a few drops of food coloring into the tank. If the color appears in the bowl after a few minutes, there is a leak.

Can I test to see if the leak is coming from the refill or the flush valve?

Yes. Shut off the water supply to the toilet. Mark the water level on the inside of the tank with a pencil. Check the water level in 10 or 20 minutes. If the water has fallen, you know the flush valve is leaking.

The water in my toilet seems to run constantly in my toilet.

If the refill valve is leaking, the tank overfills and the excess water runs into the overflow pipe and into the bowl.

How do I adjust this water level?

To adjust the water level on a conventional toilet tank, you simply bend the float arm down to lower the water level or up to raise it. Another widely popular valve has a pinch clamp that allows you to raise or lower the float.

What is a toilet vent?

It is a pipe that runs from the toilet drain to the outside, usually to the roof. This prevents air lock in the drain line.

How often should I change my furnace filter?

Normal time periods are one month to three months.

What is the advantage of the higher-priced air filters for furnaces?

They take out smaller particulates that are circulating in the air.

Will these higher-quality air filters last longer?

Actually, since they catch more particulates, they typically last a shorter amount of time. Always check the manufacturer’s recommendations.

What can I use to keep outdoor faucets from freezing?

Install a frost-free lawn faucet that is angled down to drain. For existing faucets, you can use an insulating cover.

Condensation is dripping from the water line in my basement. What can I do about this?

Pipe wrap will solve this problem.

Do you measure the diameter of hard copper the same as soft copper?

No, you measure hard copper with I.D. (inside diameter). You measure soft copper by its O.D. (outside diameter).

How do you measure galvanized pipe?

You measure it by the I.D. (inside diameter).

How do you measure black pipe?

Using I.D. (inside diameter).

I have heat tape on my water line. What type of pipe wrap should I use over the heat tape?

Use fiberglass. Don’t use foam wrap because the heat could melt it.

Installing a New Flush Valve

  • Flush valves are held to the tank by one large jam nut on the bottom of the tank. Installing a new flush valve usually requires removing the toilet tank from the bowl, which can be rather complicated. However, wall-mounted tanks may not need to be removed.
  • If the toilet tank must be removed, turn the water off completely, flush the toilet and hold the trip lever down to evacuate most of the tank water. Use a sponge to remove the remaining water. Disconnect the tank’s inlet fitting from the water supply. If the flexible riser tube is damaged, replace it.
  • Then, unscrew the two rubber-gasketed bolts flanking the flush valve. These bolts go through the tank and bowl flange, with nuts beneath. Use caution-forcing the bolts may cause you to break the tank, bowl or both. Use plenty of penetrating oil on the threads. If they still won’t budge without force, try wrapping masking tape around a hacksaw blade and sawing with the teeth facing you, so the blade cuts on the “pull” stroke. The layer of masking tape will protect the bowl’s glazed surface from saw scratches.
  • The tank should now lift away from the bowl. Lay it upside-down on a throw rug or newspaper padding to protect it, and unscrew the large nut holding the flush valve to the tank. Use locking pliers plus penetrating oil and extreme care to avoid breakage. Clamp a well-padded locking plier/wrench around the flush valve to keep it from rotating inside the tank.
  • Install the new flush valve (see image) according to the directions. The rubber gasket goes on the inside of the tank to prevent leakage. The flat washer fits on the outside to prevent tank damage.
  • Use new brass tank hold-down bolts, which will remain workable. Tighten the bolts just enough to compress the tank’s soft rubber gasket and keep it from leaking.

Installing Lavatory Faucets

  • The 4″ lavatory faucet without a pop-up drain is relatively simple to install. Place plumber’s putty in the groove just underneath the chrome framing to provide a tight seal (see image).
  • Insert the shanks of the lavatory faucet into the holes of the lavatory. Attach the locknuts and the washer to the shank and tighten them firmly into place.
  • Remove any excess putty from the base of the faucet. Connect the shank to the water supply and tighten.
  • Installing the 4″ lavatory faucet with pop-up drain is more challenging. Start by carefully reading the instructions that came with the faucet.
  • First, remove the old faucet and pop-up drain.
  • Insert the new faucet into position. Add putty in the groove around the base of the faucet.
  • Slip the washer over the shank and thread the locknut up the shank, placing the faucet loosely in position.
  • Insert the drain plunger into the center hole and affix the adjustment bar to the drain plunger.
  • Place the pop-up drain body in position and attach it to the adjustment bar. Tighten all nuts and attach the faucet to the water system. Attach the pop-up drain body to the drain system.
  • Place the stopper in the drain body and work the drain plunger. Make any adjustments by moving the lever assembly up or down in the holes provided.
  • Installing the combination lavatory faucet with pop-up drain is much the same as the 4″ lavatory faucet.
  • The main difference in this installation is that most models require the faucet handles, flanges and faucets to be removed. The assembly is then inserted from underneath the lavatory frame.

For additional information on these and other plumbing questions, check out these helpful links:

Planning and Designing Your Bathroom Unstopping Clogged Drains, Toilets and Sewers
Planning Your Kitchen Repairing Toilets
Designing Your Kitchen Replacing Toilets
Installing Plastic Laminate Countertops Replacing Water Heaters
Repairing Faucets and Valves Working with Plastic Pipe
Replacing Sink, Bath, and Shower Faucets Working with Copper Pipe

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Check your state and local codes before starting any project. Follow all safety precautions. Information in this document has been furnished by the North American Retail Hardware Association (NRHA) and associated contributors. Every effort has been made to ensure accuracy and safety. Neither NRHA, any contributor nor the retailer can be held responsible for damages or injuries resulting from the use of the information in this document.