| Let's begin by examining the traditional tank-type | | | | turned on. |
| water heater. Basically you have a big barrel of | | | | To turn on the burner water must flow in the |
| water with a fire under it. (We will get to electric | | | | pipe. When you turn on your fixture, a flow |
| water heaters shortly.) If you put the fireplace | | | | switch inside the heater turns on the burner. So |
| right under the barrel with the chimney through | | | | there is no pilot light energy being used. And since |
| the center of the barrel then you have a pretty | | | | there is no big barrel of water to keep hot, there |
| good idea of how a gas water heater heats the | | | | is no standby loss either. All is well with the world. |
| water. | | | | As with the tank-type heater, the tankless heater |
| The gas flames are not very big, so it takes up | | | | is not perfect either. Since there is no big barrel |
| to an hour to heat that barrel of water. Having | | | | of hot water, when you turn on your hot water |
| that barrel of hot water is very handy. You can | | | | you will not only have to wait for it to make it |
| take a shower and have plenty of hot water. | | | | through the house piping, but first it must travel all |
| With a big barrel several people could take | | | | the way through that long pipe. So it will take |
| showers without running out of hot water. If you | | | | longer to get your hot water. This means you will |
| want just a trickle of hot water you just adjust | | | | likely run more water down the drain than with |
| the faucet. Filling a bathtub quickly is no problem. | | | | the tank water heater, and thus waste more |
| Usually a bath faucet will produce a much larger | | | | water. |
| flow than sink or shower fixtures. That way you | | | | Another downside is that to turn on the flow |
| can fill up the bathtub quickly before the water | | | | switch you need to have at least ½ gallon |
| has a chance to cool off. | | | | per minute of flow and usually more to turn on |
| An electric tank type heater works in a similar | | | | the heater. Less than that and the heater will not |
| fashion. Heating elements similar to electric stove | | | | come on. So if you want to use just a trickle of |
| burners are submerged in the tank and heat the | | | | hot water you need that big barrel of hot water. |
| water. Heating water with electricity takes much | | | | Want to fill your bathtub...it might not be that |
| longer since the heating elements used in tank | | | | easy. Typically tankless units won't be able to |
| type water heaters are not that powerful. Heating | | | | match the flow rate of a bathtub faucet, so it will |
| water with electricity is also much more | | | | take longer to fill the tub...possibly a lot longer. The |
| expensive. | | | | bath water might cool off before the tub gets full. |
| Storage or tank-type water heaters are not | | | | The average temperature of the water going into |
| perfect. Gas heaters have to have the little pilot | | | | your dishwasher will be lower, possibly causing the |
| light burning all the time, and although small, it does | | | | dishes to not be as clean. (More cold water must |
| consume energy. Even though that big barrel of | | | | be run out of your system before the hot water |
| hot water is very well insulated it still leaks out | | | | arrives...and with a dishwasher the amount is small |
| some heat. This is known as standby loss. | | | | enough it may not even get any hot water for |
| Standby loss is what the tankless water heaters | | | | the first cycle. |
| do not have. | | | | Tankless water heaters do not work with |
| Now we can examine tankless water heaters. A | | | | traditional hot water circulating (re-circ) systems. |
| tankless water heater can be thought of as a | | | | If the circulating water does not have a high |
| long piece of pipe coiled up and put over that fire. | | | | enough flow to turn on the heater, then the |
| As water flows through the tube, the fire heats it | | | | circulating water won't be hot. If it is high enough, |
| up. A never ending supply of hot water! | | | | then the heater will never turn off. They will |
| Of course, if the tube is only a few feet long, the | | | | however work with the newer demand type hot |
| water won't be exposed to the heat of the fire | | | | water circulating pumps. The demand pumps will |
| long enough to heat it very much, especially if the | | | | eliminate the problem of running more water |
| water is flowing real fast through the pipe. So it's | | | | down the drain while you wait. |
| a long piece of pipe or tubing. When water is not | | | | Now that you have more information you can |
| flowing through the pipe the gas burner is not | | | | make a better informed decision. |