Select Page

Water Heater Problems: Water Heater Troubleshooting & Repairs

water heater troubleshooting control valve© Lee Serenethos |

A water heater’s control valve should typically be set to 150 degrees F. or lower.

Expert step-by-step instruction for water heater troubleshooting and repairing hot water heater problems such as no hot water.

Need water heater help NOW? Get a Water Heater Repair Pro Fast!

Do you need to troubleshoot water heater problems or repair your water heater? Water heater problems normally become self-evident. For example, a hot water faucet fails to summon hot water, you see dripping or puddling near the water heater, or the tank makes strange sounds. Here you’ll find expert advice for water heater troubleshooting and DIY repair.

Though some gas utility companies will solve problems with a gas water heater’s gas supply, they won’t fix other water heater problems. Either you fix it your self or you call a pro to repair it. Calling a pro often means waiting a day or two without hot water and then paying a healthy repair bill. Consequently, it helps to know how to solve basic outages yourself, as discussed below. For more difficult issues, contact a qualified local water heater repair person.

Typical water heater problems include a leaking tank (see Water Heater Is Leaking), not enough hot water, water that is too hot or not hot enough, strange noises in the tank, and discolored or smelly water. You can diagnose and handle most of these problems if you understand how a storage water heater works.

Water Heater Troubleshooting: No Hot Water

With a water heater, the most common complaint is that it doesn’t heat water at all. Because a gas water and electric water heaters are quite different, fixing a water heater that doesn’t work depends on the type. (A gas water heater has a burner at the bottom and a flue at the top; an electric one is powered by a large electrical hookup.) Please jump to one of these two pages for the appropriate water heater troubleshooting and repair advice:

Gas Hot Water Heater Problems & Repairs

Electric Hot Water Heater Problems & Repairs


Not Enough Hot Water or Water Too Hot

Two of the most common problems with hot water heaters are that they produce water that is either not hot enough or too hot. Before you do anything else, adjust the temperature dial on the front of the water heater. Wait a little while, then check the water temperature at a faucet. But if adjusting the temperature dial doesn’t do the trick, try the water heater troubleshooting methods below.


Not Enough Hot Water

An undersized water heater is usually the culprit if it seems like you never have enough hot water in your home. If the problem is chronic—or if you’ve increased your needs for hot water by installing a big new soaking tub or high-flow shower head—you’ll probably need to get a new, larger water heater. Be sure to look into tankless water heaters because, with this type, you never run out of hot water.

On the other hand, if you’ve had enough hot water in the recent past but your water heater suddenly seems to supply less hot water, first check the dial on the water heater, as discussed above. Then continue with the following water heater troubleshooting advice.

NOTE: If outdoor temperatures have dropped significantly, your water heater must work harder to heat and maintain the cold inbound water, and the water cools more as it travels through pipes that run through unheated spaces. This calls for adjusting the water heater’s dial to a slightly hotter temperature.

Also make sure your water heater doesn’t leak—check around its base for signs of water. If neither of these issues are the problem, flush the water heater tank to clear out mineral deposits. These reduce the heater’s efficiency.

water heater troubleshooting drain©HomeTips

Attach a hose to the water heater’s drain valve and empty the tank.

Also test that the temperature-pressure relief valve, which keeps pressure from building up too much in the boiler. Lift or lower its handle. Water should drain from the overflow pipe. If it doesn’t work, see How to Replace a Water Heater TP Relief Valve.

If these measures don’t do the job, the dip tube that supplies cold water to the tank may be broken or cracked. This plastic tube is supposed to direct cold water to the bottom of the water heater tank, but, if it breaks or splits, cold water pours in at the top of the tank and mixes with the hot water that is on its way to the hot water pipes.

Either have the dip tube replaced by a water heater repair pro, or, if the water heater is out of warranty and showing other signs of age, consider replacing it—a new water heater is likely to operate more efficiently.

Hot Water Is Too Hot

water heater troubleshooting adjust water heater temperature©Don Vandervort, HomeTips

Mark the water heater dial and adjust it to a lower setting.

Clearly, the first thing to do if your hot water is too hot is turn down the temperature on the water heater’s thermostat dial. Note the present setting (or mark it with a felt-tip pen), and then turn it toward a cooler setting, wait a couple of hours, and see if the problem is solved. If it isn’t continue with the following water heater troubleshooting advice:

If steam or excessively hot water shoots out of faucets, or you hear boiling sounds inside the water heater, the appliance may not be shutting off at its set temperature.

The job of the temperature-pressure (TP) relief valve is to release excessive pressure from steam buildup, but this valve may have been improperly installed, or it may be faulty. Either way, this condition can be dangerous, both because hot water and steam can scald people and because the water heater could rupture.

Turn down the water heater’s temperature and allow the water to cool, then replace the water heater’s pressure relief valve.

Hot Water Is Discolored or Smells Bad

If your water has a strange odor, first determine whether the problem is with the source water or the water heater. If the problem is with both the hot and the cold water, or if only the cold water smells, the problem is more likely with your source water. Iron, copper, and other minerals can cause discoloration in water. To solve these kinds of issues, consider installing a whole house water filter and/or a water softener.

Dealing with Hot Water Odors

If the problem is only with the hot water, in most cases the odor is caused by a reaction between the hot water heater’s anode rod and water that has a high concentration of sulfates. Let the hot water run for two or three minutes. If it smells a bit like rotten eggs, you can try flushing the hot water heater tank (see How to Flush a Water Heater). If this doesn’t solve the problem, the anode rod may need replacement. A flexible anode rod is easier than a long, rigid one to insert into a water heater if there is limited space above the tank. If you need help, call a water heater repair person.

If you smell a garlic-like scent, the pilot light may have gone out. Turn the gas valve control to OFF (you may have to push down to turn it). Wait until the gas smell has dissipated before relighting the pilot light. If the gas smell is strong and doesn’t dissipate, immediately turn off the gas supply valve, ventilate the space, and call a plumber or your gas utility company from a remote location.

HA Water-Heaters---Repair

Water Heater Makes Noises

Noises coming from a water heater can be caused by expanding and contracting metal parts; drips; or, more likely, minerals and hard water scale accumulations inside the tank or on an electric water heater’s heating elements. When heated, dissolved hard water minerals recrystallize and form scale that cakes onto interior surfaces, making the water heater less efficient and more likely to fail.

To minimize corrosive minerals through ionization, water heaters have a magnesium or aluminum anode rod, inserted through the top of the tank. To avoid scale in the first place, every few months flush out the tank. See Not Enough Hot Water for complete instructions on how to do this.

Here are some common water heater sounds you might hear:

Water heater pops, bangs, or gurgles

These sounds are caused by the buildup of hard water sediment heating up and exploding inside the tank. You can flush out the tank yourself, although by the time you’re hearing this sound the sediment chunks may be too large to pass through the drain valve. For more, please see How to Flush or Drain a Water Heater.

If you have an electric water heater, these sounds could indicate a buildup of scale on your heating elements; it may be time to replace these.

Water heater makes a boiling sound

If water sounds like it is boiling inside the tank, this could indicate overheating and a dangerous pressure buildup. Call a service professional immediately.

HA Water-Heaters---Repair

More Water Heater Repairs & Tips

For step-by-step instructions on specific types of hot water heater repairs, next see:

Here are a few helpful tips regarding safe, efficient water heater usage:

water heater troubleshooting foam pipe insulationFrost King

Foam pipe insulation can prevents heat loss through hot-water pipes.

• Check the water heater’s temperature setting. Set the temperature control to about 150 degrees F. or lower if you have no dishwasher or if you have small children or elderly people in the home who might scald themselves.

• Insulate hot water pipes. To minimize the energy it takes to heat the water, insulate your water pipes if they run a long way from your heater to your faucets. If you can gain access to your hot-water pipes, from the basement, for example, put foam water pipe insulation sleeves onto them to minimize heat loss.

• Periodically check the temperature-pressure relief valve, which keeps pressure in the boiler from building up too much. Lift or lower the lever on this valve. Water should drain from the overflow pipe. (For more about this, see How to Replace a Water Heater’s TP Valve.)

get a water heater repair pro

Featured Resource: Find a Local Pre-Screened Water Heater Pro

Call for free estimates from local pros now:

Join the Conversation

  • Fatboyslick

    When I turn on my hot water the tank makes an horrendous noise…as if building up the pressure to take off. Then suddenly the sound of flushing occurs and the loud noise wears off…only for it to start again.
    It lasts about 39mins or until I turn on the hot water

  • Bert

    I have a closed water system. (a one=way valve was installed about 3 or 4 years ago). My T & P valve on my electric hot water started leaking occasionally. I replaced the T & P valve but same thing happened. I installed a pressure gauge on the system, and after a large drain of hot water the pressure would increase to 150 psi. Turning on any tap momentarily reduced the pressure to system pressure (50 degrees F). I am contemplating installing a thermal expansion tank. Is this the only remedy?

  • William Lenk

    I have an electric hot water heater off my kitchen in a small house. When I flush my toilet on the opposite end of the house I hear water running at the heater until the toilet shuts off. All is working ok.

  • Dougie Mac

    Too much gas is being released before the flame from the pilot light gets to it causing a lot of explosion how can I fix this? Should I put the pilot light underneath where the gas comes out? The pilot light is currently on the right side of the pipe where the gas comes out takes up to a minute to light causing a lot of explosion and the boiler shaking my doors it’s pretty scary I need help here thank you so much

    • home_tips

      Anytime you feel there is a gas leak or risk of explosion, call the Gas Company right away!!

    • Don Vandervort, HomeTips

      This sounds very unsafe. Please call your gas utility or a water heater repair person.

  • Jessica Davis

    My gas hot water system has no pressure. My cold water has lots of pressure but the hot water is barely a trickle. It’s not too bad in summer not looking forward to winter? what could be the cause?

    • Don Vandervort, HomeTips

      Make sure there isn’t a valve partially
      closed either coming or going from the water heater. The chances are good that
      some scale from mineral deposits chipped off the inner surfaces of pipes and
      partially clogged the pipes somewhere. Sometimes you can clear this by back-flushing the hot water system.

    • toddpeterson

      Jessica, you don’t get your hot or cold water pressure from your hot water tank. You get it from your city line. Also known as, mainline. The closer you live to a water tower the better the chances of your water pressure. It’s not uncommon to have really high cold water pressure, but since most pipes have to be double insulated for hot water it will come out much softer. I hope you understand and I hope this helps. I recommend if it’s too bad to contact the city you live in and the water department. Good luck

  • josh

    I have a propane hot water heater I just replaced with a new one. I also changed from well water to county water and installed a pressure valve in line with my main line. Now every time I turn my pressure up the temperature releif valve pops. The temp on the water heater is set low. The pressure on the house has to be set extremely low to keep this from happening. Can someone please give me advise on what to do to fix this problem

    • Don Vandervort, HomeTips

      Sounds to me like a defective pressure relief valve, but I’d like to have a plumber weigh-in on this…

  • Don Vandervort, HomeTips

    Sounds to me like a defective pressure relief valve, but I’d like to have a plumber weigh-in on this…

  • John

    I am not getting hot water water in my home. It’s lukewarm at best. Although when I check my hot water tank and open the pressure relief valve, the water comes out hot. Why is it that this hot water isn’t making it to the faucets? Please help. Any suggestions?

  • Faaris

    I have a fairly new gas hot water heater 40 gallon tank and when the kitchen faucet is being used there is not enough hot water to supply the other rooms such as the upstairs bathroom if both are used at the same time. Could there be an issue with the hot water tank or should the pipes be insulated? Thanks.

  • Tyler

    Cleaned the pilot light and had a new pressure relief valve installed but now I can’t turn the heat up past notch B without water coming out of the prv and pilot light blowing out? Any suggestions why this is happening?

  • The cold water supply entering a water heater may drop as much as 25 degrees during the winter. This temperature difference will cause a water heater to recover much more slowly.

  • Shane Stewart

    If a water heater isn’t completely level would that be a reason why the pilot light won’t stay lit?

    • toddpeterson

      I wouldn’t think so Shane. We had a hot water heater in a few rent houses put in the garage and the contractors had to have the heaters on level approximately an inch and a half. We never had any problems. May try to replace your thermal coupling. Very easy fix, step-by-step instructions on youtube

  • Marian Robertson

    I just moved into this townhouse last December. I recently had the water heater (rental) company service man out to replace the rod in my electric water heater, as the hot water was discolored. Apparently the rod should have been changed 2 years ago. The heater, I am told, is 10 yrs. Old. I believe it uses a magnesium rod. Ever since the rod was changed I have had a lot of air in the hot water lines both to my kitchen sink and my bathroom sink. It is similar to when the water has been shut off for repairs, when you turn it back on the air has to be cleared. Well, it is now 2 weeks since the rod was changed and I am still getting all the same spurting and splashing going on. I had the service man out 2days ago, and he asked how much water I use, if I had been away, etc. I live by myself but I shower regularly, run my dishwasher, my washing machine, etc.,etc. I have not been away. The service man claims that the new magnesium rod is causing a release of hydrogen gas in the water because of the reaction between sodium, magnesium, and chloride. When I run the hot water it comes out whitish and looks quite milky in a container. I understand this is air in the water and it clears fairly quickly. The service man thought my water softner may be backflushing into my water heater when it recharges at night. Is this possible, or is the service man feeding me a line?

  • I admire the valuable information you offer in your blogs. I will bookmark your blog and have my children check up here often. I am quite sure they will learn lots of new stuff here than anybody else!

  • Josh Truax

    I have a 40 gallon gas water heater and when the burner shuts off after heating the water the pilot light goes out I’m pretty handy but I just don’t know about this

    • Matthew Strenn

      Any luck? I have a similar problem

    • Larry Hinton

      It’s most likely the thermal couple needs replaced.

  • Taylor Black

    can I replace broken drain valve at bottom of 50 gal. tank?

    • bc_california

      Turn gas off and let it cool down (depending how hot the water), turn off inlet water supply valve to tank. connect a garden hose to the spout of the drain valve and run hose outside for draining, open the drain valve and also loosen the cold flex water line at the top of water heater to let air into the tank as water leaves it. Tighten water flex line. Replace faucet with same pipe thread type and open water inlet valve to refill and open a hot side faucet in sink to let air out, when water comes out it is full.

  • karen

    Oil heated hot water furnance is making hot water and comes on when desired but is not heating the home. The thermostat has been replaced. Any other suggestions of what could be wrong to find out why not heating the home?

  • Randy

    I have a gas water heater and its having a issue. When I first get up in the morning to take a shower the water is just luke warm. Throughout the day the water is perfect. It’s like the water heater goes dormant durning the night and does not maintain the heat of the water. You guys have and ideas what this could be? Any advice is good advice

  • toddpeterson

    I was at work, my wife called and stated that our hot water heater spraying water everywhere. Her father came over, and I found out it was just the hot water relief valve. I understand this is important as it could have blown up. I believe The temperature was set too high. So we cleaned up all the water, drain the tank halfway, which is 40 gallons. But now The burner will not stay lit. Actually, it won’t light. When I hold down the gas button the thermal coupling will lights but the burner will not catch fire. When a hot water relief valve goes off does it get water inside where the burner is and cause more moisture? It has been almost 24 hours, and still the same thing. Do you think water got on the burner and ruined it, or should I wait a little longer ? Thank you for your response in advance .

  • Joseph Massimino

    I replaced a electric water heater, and I have done plenty of them. This last one was for my brother and when he turns is hot water on, he gets some air in the line, like it spits some air out with the water. I’m am baffled, how is air getting into the hot water line?
    I have a pressure releaf tank, mounted upside down, and other than that, it all works well and does not leak. Does this spitting of air in the hot water ring any bells for anyone? I lowered the pressure releaf tank pressure to match the city water pressure. To me, this is too simple to not work perfectly.

  • Lara Watson

    We have a large hot water cylinder but we run out of hot water after 1 shower. Any idea what might be causing this?

  • Chris Vaught

    I replaced my electric unit less than a year ago with no issues in hot water supply. My problem is a sound started occurring the best way I can describe it is it sounds like a small air compressor in the wall. It only lasts for6seconds seconds and then stops with no reason. I’ve removed the drywall where the manifold is none of the pipes are viberating and have also checked for vibration at heater to wall location.

  • cherylbatic

    I have solar hot water that is backed up by electricity but some days I don’t have hot water until 11.30 at night when the J tariff cuts in.. can I do anything about this ?

  • Steve Price

    I have a gas water heater. The pilot is working. The gas starts flowing but doesn’t light right away. When it does there is a big flash of fire and it sounds like a jet engine. So to much gas for sure any suggestions why?

  • Danille Grissom

    I have a gas water heater and when I light it, it stays lit for a while, but goes out again. Now I tried to relight it and it wont relight. What do you think my problem is?

  • Risa Simon

    I had a new thermostat installed on my gas water heater.It is set on a proper temperature.but it takes about 10 minutes of running the water before it turns hot. Someone mentioned they think my repairman didnt open up the inlet valve enough…Do you agree, and where is that valve please. Thanks alot.

  • WittoStevie

    “Expert step-by-step instruction for water heater troubleshooting and repairing hot water heater problems such as no hot water.” Why would anyone want to heat hot water?

    • Don Vandervort, HomeTips

      I like your thinking—and chuckled when I read this. Actually, “hot water heater” is a commonly-used colloquial term. When you think about it, we all want to heat hot water to keep it up at the correct temperature. As a result, a conventional water heater is filled with hot water that is continually heated. Thanks for visiting HomeTips. :)

  • Bernadette Robinson

    my gas hot water heaters pilot wont stay lit got a new thermocouple but still having the same problem

  • Dee Mcbride

    my dad just replace the element in our electric hot water heater and it get hot but we have to flip the bottom after someone ues the hot water what might be the problem?

  • raven1041

    I have a propane water heater and I want to add an electric water heater so I can use one or the other when I want to. Should I put a check valve on the outgoing hot water lines from each heater so hot water from one heater won’t run back into the other one, or would it be fine without check valves?

  • Eileen Keenan

    We have just tried to turn on the water at our cabin after the system being drained and shut down for the winter. Water flows into the electric hot water tank but none comes out. we filled the tank until water came out of the overflow into the drip pan below. Is there any type of safety valve or anything that could be preventing water leaving the tank? when we disconnected the exit pipe and put a screwdriver into the opening there is definitely something obstructing the exit connection. Any ideas what could be wrong?

  • ng joo ooi

    I mean the valve of LOW/HIGH water volume controller was faulty. Any idea to bypass it. Can anybody advice to increase the water volume flow ?!

Share This