A small amount to keep the pilot light going.
Spillage excessive condensate bad thermocouple draft
Thermocouple. Keep pilot knob depressed for 30 seconds after lighting pilot.
No because water heaters have a safety valves and when the pilot light goes out the safety valve shuts off the gas
My direct vent furnace pilot light issue was the glass viewing port was missingallowing room air to blow out the pilot light. Replacing the missing glass which stopped the draft, fixed the problem.
The thermocouple is going bad. The thermocouple is the small tube that sits in the flame from the pilot light and goes back to the gas valve. They are easy to replace and cost $6 to $8. For health and safety the failing part should be replaced without delay by a competent gas engineer.
If it is windy outside, you may be getting just enough of a breeze to blow out the pilot light -even though the covers are shut. My heater is in the garage, and even w/ the garage door shut and the covers on the heater shut, very windy weather can still cause enough of a draft to blow out the pilot. You could try to find something to block drafts around the heater such as a hot water heater blanket.
No If the hole is smaller then the diameter of the supply line
A number of problems can cause a swimming pool heater not to work. The most common I have found is lack of water flow. A heater needs a certain amount of water flowing through it to work correctly. The next most common problem is due to the pilot not lighting or remaining lit. This is usually due to the pilot generator not working. When you light a pilot light and have to hold it for a length of time before releasing the button you are allowing the pilot generator to heat up and then stay open to keep the pilot lit. Usually you need a licensed person to do work with changing items on a gas unit. The thermostat can be a problem for any water heater. Most of the heaters I have worked on were gas. If you have an electric heater waterflow still needs to be checked and the electrical connections can become corroded in the presence of chemically treated pool water.
You can turn it down so that it doesn't come on much. If it is a gas heater, the pilot light might provide enough heat to keep it from freezing, but that is not certain. If there is not going to be any heat in the building, the pipes need to be drained, the heater also and anti freeze put in the drains and the toilet. This anti freeze is different than what is used in cars.
The pilot light burner probably needs adjustment and cleaning.
Check your instructions, Usually you have to keep it on pilot mode for 30 seconds then you should be able to turn it to on without the pilot flame going out.
No, that is part of the function of the pilot light. To light the burner and to keep the gas valve open. The thermocouple sits in the flame of the pilot and produces a small electrical current that keep the gas valve open. When the tank cools down, the thermostat opens the valve to the burner so that it can light. When the pilot goes out, it is usually the thermocouple that is bad.
Why does the water cycle keep going?
form_title= Gas Water Heater form_header= Install a gas water heater in your home! Are you repairing an existing gas water heater?*= () Yes () No () Not Sure Do you want to install a new gas water heater?*= () Yes () No () Not Sure How old is your home?*= _ 
It stays on UNLESS you have a commercial heater with an electronic ignition
"Gas hot water heater"? Why would you want to heat water if it's already hot? Down draft (spillage) Defective thermocouple Dirty fuel tube supply Improper venting Excessive humidity Excessive condensation No enough FREE AIR for proper combustion To much blow back When in doubt hire a Licensed Master plumber /gas fitter
There could be a draft causing the pilot light to go out.
It will keep the water hot as long as the electricity or gas is on. If it's going to be off more than a day, turn the breaker or gas valve off.
There is no shut off valve. But you can by pass the heater core by disconnecting the 2 hoses going to the heater core. And connecting them together. The only problem with this is that you won't have any heat in the winter.
On a stove it will. On a modern, code-compliant water heater, space heater or furnace it will not, because these modern appliances have electric valves that will not open if the pilot flame goes out. Once the pilot is out, the only way to get gas to flow is to push the pilot button in on the gas valve and relight the pilot flame according to the instructions. You can check for gas leaking from the pilot burner or main burner by smelling for the scent of gas, as natural gas and LPG (propane) have an odorant added to allow you to detect their presence. (Do NOT use a flame or spark to test for the presence of gas!)
form_title=Water Heater Repair form_header=12213 Choose any description for the problem*=  No hot water  Not enough hot water  Pilot light is out  Leaking tank  Hot water fluctuations  Leaking or cracked pipe  Making noise  Want to move to other location  Want to replace with different type  Other Do you know the size of your water heater you have now?*= () 30 Gallons () 40 Gallons () 50 Gallons () No water heater () Other "If a replacement is required, would you like the same type?"*= () "Yes () No, I want a different size () No, I want a tankless water heater () No, I want a solar water heater () No, I want to change to electricity () No, I want to change to natural gas () No, I want to change to propane gas () Don't Know" What is the source of heat the water heater is using?*= () Electricity () Natural gas () Propane () Don't Know
Tankless. A tankless heater heats the water as you use it. It doesn't store hot water and keep it hot day and night whether any is used or not. The water is heated almost instantaneously, and the heater will keep the hot water flowing as long as the water is turned on.
Firstly, how old is your heater? Do you in fact have a pilot light or is it an electronic ignition heater? If the latter, it has no pilot.Older heaters have a gas valve knob that is rotated to "pilot" and then when ready with the ignition source, match, push the knob down and hold while holding the ignition source near the pilot flame outlet. Hold knob down for about 1 min. while pilot generator heats from that flame then let go and if the flame stays lit then rotate the knob to "heat" or "fire" or "run". In a brief amount of time the heater will fire. BE SURE TO KEEP FROM LOOKING INTO THE FIRE BOX TO WATCH THE HEATER FIRE!!!!!! STAND BACK FROM THE OPENING - YOU COULD GET BURNED OR AT LEAST LOOSE A LOT OF FACIAL HAIR AND/OR BE TERRIBLY FRIGHTENED BY THE RESULTING BLAST. Close and secure the heater door and listen for the combustion chamber to run continually.If pilot does not stay lit then it is possible that the pilot generator needs to be replaced.K