Building a New Home? Go Green with Your Plumbing Layout!Be environmentally friendly by giving your new home a green plumbing system. |
All About Water Heaters and Water heating
Electric Water Heater Operation Electric Water Heater Repair Traditional Type Cold Water Return |
|
|
Which Kind of Water Heater; Solar, Tankless, Storage, Point-of-Use or Heat Pump? There are a variety of ways to heat your water. There are natural gas storage and tankless water heaters, propane heaters, electric heaters, wood fired heaters, boilers, solar, geothermal, heat pump, and probably some I have forgotten. For this article I won’t get into the exotic stuff like
geothermal, but stick to typical residential water heating methods. Solar Hot Water Heaters Solar hot water heaters can be a great bargain, providing very inexpensive or even free hot water. On or on the other hand they can be some of the most expensive. There are two basic types of solar water heaters, passive and active. Passive solar systems don’t have any pumps, automatic valves, or controllers. They are called passive because they have no moving parts or controls. Active solar systems use pumps, valves, and other devices and controls making them more efficient and expensive than passive types. They can also fail more often and can be expensive to maintain. Geographical location is very important with solar water heating. If your location is not subject to freezing temperatures If you are in an area where it never or rarely freezes then a passive system might be a good option. There are different types of passive hot water heating systems. There are batch systems, which basically consist of a tank of water in a miniature green house, and systems that use solar collectors. There are of course many variations of the passive type systems, collectors in series, in parallel, with and without storage tanks, back up resistance heating etc. If you live where freezing is a problem then you need an active system of which there are also many variations. Some heat the water directly, some use an anti-freeze solution in the collectors, some drain the water out of the system when it approaches freezing etc. Ideally if you want a solar hot water heating system you
live in a warm climate with an abundance of sunshine. Due to the high initial
cost of most solar water heaters or water heating systems the payback is usually
many years. Storage Water Heating My opinion is that storage water heaters are almost always a good way to go. Standard gas and electric water heaters are a commodity product. Parts are easy to come by, nearly any plumber can fix them, and if you need to replace one it’s easy to do, probably the same day. With a tank type water heater the usually first sign of trouble is the tank begins to leak. A puddle under the water heater provides you with advance warning that you need to replace the water heater. If something does go wrong with your natural gas or electric storage water heater just about anyone in town can fix it in an hour.
Heat pump water heaters are a more efficient at heating water than most other methods as long as it’s not too cold outside. Instead of creating heat, heat pumps just move the heat from one place to another. The heat is transferred from the air outside your house to the water inside the water heater. They work just like your air conditioner. There is a heat exchanger inside the tank that heats the water and a heat exchanger outside that sucks the heat out of the outside air. However, there needs to be some heat in the air. Heat pump water heaters take longer to heat water than electric resistance heaters, which take longer than gas water heaters. As the air temperature decreases the heat pump water heater will heat more slowly. The initial cost is of course fairly high in comparison to storage gas and electric models. Heat pumps can also gather the heat from under the soil by circulating water through sub surface piping and using that for the heat pumps source of heat. Heat pumps generally have backup resistance heating available for when the weather gets too cold for it to operate properly.
With the reputation for being “green” tankless hot water heaters are all the rage. Tankless water heaters do not have the standby losses inherent with tank type hot water heaters and the savings isn’t a whole lot. A tankless heater will save you about $5.00 a month. Most tankless water heaters are gas types. To heat water rapidly with an electric heater the amperage draw has to be so high that typical residential wiring isn’t heavy enough. Heaver wiring must be run to the heater and in some cases the service to the house from the utility company needs an upgrade. That can be very expensive. Tankless water heaters (gas), need larger venting than storage heaters, and often the venting has to be made of stainless steel which is expensive. Gas tankless water heaters also need a larger gas line than gas tank type heaters. When there is a power outage most tankless water heaters will not work. With a tankless water heater you must keep a minimum flow rate or the heater will shut off. Typically it requires about ½ gallon to ¾ gallon per minute of hot water flow to keep the heater turned on. If you are using a mixed flow to reduce the temperature then you may need to run some low flow fixtures at full blast to prevent the heater from shutting down. Installation is very important with tankless water heaters
and should only be done by someone who knows what they are doing, preferably a
plumber factory trained with the brand of heater he is installing. Poor
installations can cause problems years down the road. Point-of-Use Water Heating Point of use water heating refers to the hot water distribution system as much as it applies to the water heater. Any kind of water heater is a point-of-use heater if it is very close to the fixture. Homes can be designed with the bathrooms and kitchen arranged so that the hot water runs are all very short. It can save large amounts of water compared to a plumbing layout with long pipe runs. |
||