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How To Drain a Water Heater
Knowing how to drain a water heater will make doing various repairs and maintenance items on your water tank much easier.
When would you need to drain your tank? A common task is 'removing sediment' and 'flushing the water tank'. Other tasks, such replacing an 'anode rod' or a 'dip tube' will require that the tank be partially or completely drained.
For related information, see 'Troubleshooting Electric Water Heaters' and
'Gas Hot Water Heater Troubleshooting'. These articles contain common problems and the resources to get them fixed.
You also have to drain the tank when you need to 'repair or replace the drain valve'. These valves are prone to leaking of often break when you attempt to tighten them.
With electric water heaters, the heating elements cannot be changed without draining the tank.
Shutting Down the Hot Water Tank
You cannot drain a hot water tank while it is turned on. The heating elements and the tank can be damaged. Not to mention the danger in leaving a tank operational while you are working on it.
The first step will be shutting down the hot water tank. This actually involves a few steps and is different for gas and electric water heaters. The correct procedures for doing this are covered in the articles on 'Shutting Down an Electric Water Heater'
and 'How To Shut Off a Gas Water Heater'. Read this information before proceeding with any draining activities.
Part of the procedure for shutting down the water tank includes cooling the water. This is a safety precaution, the water inside your tank can be very hot and cause burns. It is best to 'cool off the water' prior to working on the tank.
Where Should the Hot Water be Drained To?
Assuming that you have followed the procedure for shutting down the water tank, the water inside the tank should be just warm. This will not damage drains or plumbing fixtures.
A floor drain is the ideal place to drain the water into. Locate a floor drain near your hot water tank.
If you do not have a floor drain, you can drain the water outside. Warm water should not damage concrete or grass. Find a suitable location to drain forty or fifty gallons of hot water to.
Hooking Up a Drain Hose
You will need a hose that is long enough to reach the drain or other location that you are going to drain the water to. The female end of the hose will hook up to the water heater drain valve. You should use a pair of pliers to get it on tight.
Stretch the hose out so that it will drain. The hose should be lower than the drain valve on the water heater. There won't be any pressure when you drain the tank. It will only be gravity that allows the tank to drain.
Allowing Air to Get Into the Water Tank
If you followed the 'shut down procedure', you should have opened up a hot water faucet somewhere in the home. This will allow air to get into the tank when the water is draining.
Make sure that the faucet is open, (preferably somewhere above the hot water tank) prior to opening the drain valve. When you are certain that valve is open, you can open the drain valve.
Water heater drain valves do not get used very often, so you may need to use a pair of pliers. Some drain valves are made of plastic, so be careful when you attempt to open it. If you damage the valve, now would be a good time to replace it. See the article on 'replacing a water heater drain valve' for instructions on how to do this.
Draining the Hot Water Tank
It will take some time for all of the water to drain out of the tank. Most hot water heaters have between 40 and 60 gallons of water in them. This would also be a good time to 'flush your hot water tank', see this article for what to do.
Now you should be ready to make repairs or perform other maintenance on your hot water tank.
Water Heater Pilot Light Igniter
Using a water heater pilot light igniter is easier than matches or hand held lighters. Many newer models have them. You just have to follow the instructions and then depress the button a few times.
Not sure if this is what you need to do? See the article on 'Gas Water Heater Troubleshooting' for a complete list of problems and thier corresponding solutions.
How To Tell If You Have an Igniter
A water heater igniter has a sparking tip that is directed at the location of the pilot light. You should be able to see it above or next to the gas supply line for the pilot light.
The other tell tale sign is the wire that runs from the gas valve to the igniter. Most water heaters do not have any wires attached to the gas valve.
The igniter is also likely to have a separate button that has to be pushed to engage the sparker.
Following the Instructions
The lighting instructions are different on each water heater. Read the instructions and follow the steps. You will usually turn the dial to pilot and hold down the button. Then press the igniter until the pilot lights. Hold the button down for as long as it tells you.
See the article 'Following Pilot Light Lighting Instructions' for information on how to locate the instructions and why it is important to follow them.
Lighting Procedure
The first thing you will want to do turn the temperature setting to its lowest position. Then turn the gas vavle to 'Off'. You should wait about ten minutes before you do anything else. There may be some lingering gas that you want to dissipate before you try to light the pilot.
The next step is to remove the outer cover from the burner assembly. It should snap off. There is a small view window that allows you to see the pilot light. Make sure it is cleaned off. A small flashlight would not hurt at this point.
Watch through the glass and make sure the pilot stays lit. Wait the proper amount of time and turn the gas valve to on. After that you can set the thermostat to the desired temperature.
If the water has been off for any length of time the burner should light right away. Make sure it is burning properly and replace the outer cover.
What If the Pilot Light Does Light
Normally you would get concerned if you followed the instructions and the pilot light failed to light. With an igniter, you may have a problem with the igniter itself. If you have ever used the igniters on a gas grill, you know what I am talking about. They are not always the most positive lighting method.
You can still light the pilot light using a traditional match or long lighter method. You will still need to follow the instructions and go through the procedure again. See the article on 'Manually Lighting a Pilot Light' for more information.
If after you have tried the traditional method, you find that the pilot light won't light or won't stay lit, you likely have another problem. See the article 'Problems With Water Heater Gas Valves' for a pilot light that won't light at all. For those that won't stay lit, it is likely the thermocouple, see the article 'Troubleshooting Water Heater Thermocouples' for instructions on what to do.
How To Light a Water Heater
You need to know how to light a water heater when your pilot light goes out. Without the pilot light a gas hot water heater will not work and you won't have any hot water. Lighting the pilot light will take about fifteen minutes.
Not sure if this is your problem? See 'Gas Hot Water Heater Troubleshooting' for a complete listing of all the possible problems and how to solve them.
Lighting Methods
Manual Method
For most hot water heaters, you do not have a choice. You need to use a long match or utility lighter. The reason is that the pilot light is inside of the water heater a few inches and it is difficult to reach. A lighter is a much better choice since the flame will remain constant.
The best tool for the job is a 'Utility' or 'Multi Purpose' lighter. This is the style with a long nose on it. They are ten or twelve inches long, plenty long enough to reach the pilot light inside opening.
Igniter Method
Some water heaters are equipped with an igniter. These are similar to the igniters on a gas grill. The article 'Lighting a Pilot With an Igniter' has information on this method.
Following the Lighting Instructions
Different water heaters have different procedures for lighting the pilot. Usually, there is a waiting period involved before can turn dial to pilot.
Look on the side of your hot water tank and read through the procedure that is required for your water heater. Failing to follow these instructions may result in the pilot not lighting. This topic is discussed further in the article, 'Following Pilot Light Instructions'.
Lighting the Pilot Light
The following is a general description of the steps involved. Make sure you read the instructions on your water heater before proceeding, they may differ from what is stated below.
Make sure that the temperature setting is on its lowest position. Then turn the gas valve to 'Off'. You should wait about ten minutes before you do anything else, or as long as the instructions indicate. There may be some lingering gas that you want to dissipate before you try to light the pilot.
The next step is to remove the outer cover from the burner assembly. It should snap off. There is usually an inner cover that you will also need to remove. A small flashlight would not hurt at this point. Do you see where the pilot assembly is? Good, you want to make sure you have a long match or grill lighter that can reach it.
You will usually turn the dial to 'Pilot' and hold down the button. Make sure you are ready with the lighter or match. If the pilot does not light quick enough the gas valve will shut down and you will have to wait again. Light the pilot and hold the button down for as long as it tells you.
Watch through the glass and make sure the pilot stays lit. Wait the proper amount of time and turn the gas valve to on. After that you can set the thermostat to the desired temperature.
If the water has been off for any length of time the burner should light right away. Make sure it is burning properly and replace the outer cover.
What If the Pilot Does Not Light
You followed the instructions, tried a couple of times and the pilot will not light. Another situation is a pilot light that will not stay lit. What do you do?
You may have another issue. A pilot light that lights initially and then goes out is the sign of a bad 'Thermocouple'. See the article on 'Gas Water Heater Thermocouples' for more information on what to do.
If the pilot light will not light at all, it could be the gas valve that is the problem. See the article 'Hot Water Heater Gas Valves' for information and options on what can be done.
Summary
Following the instructions above, you should have been able to successfully light the pilot light on your water heater. If not it is possible that you have another problem.
Water Heater Lighting Instructions
Lighting a pilot light for a gas hot water heater is not a difficult task. However, it can be irritating if you don't follow the instructions for your particular hot water heater.
You need to follow the sequence that is indicated and wait the prescribed amount of time before you attempt to light the pilot. If you don't the gas valve may not allow gas to go to the pilot light. If it doesn't light, you will not have hot water.
Not sure if the pilot light is your problem? See the article 'Troubleshooting Gas Water Heaters' for a complete listing of all the topics and links to resources for solutions.
Locating Water Heater Lighting Instructions
In the Owner's Manual
If you have the 'owner's manual' that came with your water heater, the lighting instructions for the pilot can be found there. Sometimes the manual is in a packet that is attached to the side of the water heater.
If you know the make and model number of your water heater, you can try and find the manual online.
On the Side of the Water Heater
Water heater pilot light instructions are found permanently fixed to the side of the tank. There are usually several steps, that involve waiting. These are meant for your safety in the event there is any unburnt gas left in the air.
The instructions for lighting a water heater pilot light are a little different for the various models. You will want to take the time to read them and make sure you understand the steps involved.
Pay particular attention to how long you have to wait. Additionally you want keep the button depressed the proper amount of time. Gas valves are fickle and they won't won't send gas to the pilot if you don't follow the instructions.
If you fail to get the pilot light lit the first try, you have to start over. The waiting periods will apply. These are safety precautions.
Lighting Instructions
For some pointers on how to light the pilot light, see the article 'Lighting a Water Heater Pilot Light' for instructions on using a utility lighter to light the pilot.
Some water heaters are equipped with igniters. If you have this type, see the article 'Using an Igniter to light a Pilot Light'.
Summary
Water heater gas valves are very tempemental, so you need to follow the instructions carefully when you attempt to light a pilot. Otherwise, you may be frustrated, when the pilot light won't light. Do not assume that you have another problem with your water heater unless you have followed the lighting instructions carefully.
If you still cannot get it to light, it could be a problem with your 'thermocouple' or the 'gas valve', follow these links for more information.
Water Heater Pilot Light
A water heater pilot light is used to ignite the gas that heats the water. You may go for a long time and not realize that your pilot light has been faithfully serving you.
When the pilot light stops working you do not have hot water. Then you notice. A malfunctioning pilot light may be a sign of another problem. It could be that it just needs to be lit again.
There are (4) Key Topics related to this subject. (1) Why it is important to 'Following the Instructions', (2) 'Using an Ingnitor' to light your pilot light, (3) 'Manually Lighting a Pilot Light' and (4) Other pilot light issues like the 'Thermocouple' or the 'Gas Valve' may need some additional attention. Use one of these links to find what you need or read the overview below.
Don't they have electronic ignition systems that will just light the gas when needed? Yes, they do. Most gas furnaces have such a system. Why don't water heaters? They do, but it is a matter of cost. A high efficiency hot water heater with electronic ignition will run you a $1,000 or more. Whereas, a standard gas model might be as little as $350.
The added cost results in the majority of units still using a water heater pilot light. This article will help you with the issues that a pilot light can cause.
Water Heater Pilot Light - Information
What Can You Save?
A serviceman that comes out will likely tell you your problem is a defective thermocouple. The bill for replacing it will be between $125 and $150. Up selling you to a new water heater is also a possibility. Plan on $800 to $1,500 if that happens.
How Hard Could It Be?
Lighting a water heater pilot light is not that hard. It should take less than ten minutes.
Check the Simple Things!
You're at the simplest problem you can have with a gas hot water heater. Sorry, there is nothing easier.
What Can Go Wrong?
A pilot light that won't stay lit may be indicative of a more serious problem. You will be without hot water if you cannot fix it. You can get a lot of complaining when this happens.
Troubleshooting Pilot Light Problems
There are two types of pilot lights that you may need to deal with. The older style that requires a match to light it. Then there are the newer ones that have an ignitor. Some high efficiency hot water heaters use and electronic ignition and do not have a pilot light.
Gas water heaters are equipped with a thermocouple, this is a safety feature that keeps the gas valve from allowing gas to flow when it is not being burned. See the questions below to try and narrow down your problem.
The Pilot Light Is Out
When the pilot light goes out completely there are a few possible explanations. As with many problems, you want to eliminated the simple and obvious things first. So we will address this problem from that standpoint.
No Gas
Was the gas supply interrupted for any reason. There could be many possibilities. We list some of the possible reasons below, but there could be other reasons. The simple thing to check first would be whether or not you have gas to other devices, such as a stove or oven.
Even if the stove or oven lights now, it does not mean that the gas was not shut off for a brief period of time. Other gas devices have ingniters that will ignite the flame after the gas supply is restored. Your water heater probably does not have this feature. See the list below and see if any of the possible situations may have happened. If the gas supply was intterrupted even for a short period of time, you will need to 're-light the pilot light'. See the article on 'lighting a pilot light' for instructions on what to do.
Reasons for Loss of Gas Supply
Pilot Light Blown Out - Is there a chance that a strong gust of air might have blown the pilot light out? This is more likely when the water heater is in a closet that is used for other things that may require the door being opened repeatedly. This is a strong possiblilty if the outer or inner cover plate has been removed for any reason. The pilot light is a small flame no bigger than a butane lighter flame. If a gust of air gets to it, it will blow out.
Working On Gas Devices - Did you work on any other gas devices in your home? Maybe you were working on the stove or a gas dryer. Of course the safe thing to do is shut the gas off before you work on the appliance. Unfortunately, even if the gas is only shut off for a few minutes, it will cause the pilot light on a gas water heater to stop working. If the thermocouple does not sense continuos heat from the pilot light, it sends a signal to the gas valve and no more gas will be sent to the pilot light. This is a safety feature to prevent natural gas explosions. If this has happened, you need to go through the process of lighting the pilot light. Before you proceed with the lighting procedure, make sure you have turned the gas back on. See the article on 'lighting a pilot light' for instructions on what to do.
When this happens lighting the pilot again is the only solution. See the article on 'lighting a pilot light' for instructions on what to do.
Utility Work at the Street - Has any utility work been done at the street, in front of or near your home? Many times it is a safety precaution to turn the main gas line off when utility work is done. If you are unsure, a call to your gas utility provider will tell you if there have been any intterruptions in the supply. Again, even if the gas was shut off for a brief period of time, the pilot light will need to be lit again. Verify that the gas is back on and see the article on 'lighting a pilot light' for instructions on what to do.
Shut Off by the Utility Company - Okay, we're all imperfect and things happen. Did the bill not get paid, for whatever reason? Maybe it was an oversight. Maybe you were trying to stretch things a bit. Maybe the utility company failed to credit a payment. Lots of possibilities here, no shame, just a situation to deal with. Do you have gas to any other devices in your home? If other things are working, then it is just the water heater, see above.
If everything is off, you will need to contact the gas utility and determine the problem. If they shut it off for any reason, once the matter is resolved, you will need to wait until they come out and restore the service before you can light the pilot light. If this has happened you will definately need go through the lighting instructions. See the article on 'lighting a pilot light' for instructions on what to do.
Pilot Light Will Not Stay Lit
If you have followed the lighting instructions correctly, the gas valve should allow the pilot light to continue to have gas. When it will not stay lit it is a sign of a defective 'thermocouple'. The thermocouple senses heat from the pilot light and sends a signal back to the gas valve. When they fail the gas valve will not open. See the discussion on 'gas water heater thermocouples' for more information.
Pilot Light Will Not Light
There is a procedure that needs to be followed when you light the pilot light. See the article on 'locating the pilot light lighting instructions' for more information.
The other possibility is a defective 'thermocouple' or 'gas valve'. Follow these links to determine if this is your problem.