Gas tank water heaters have been the most common source for heating water in the Bay Area for decades. Gas is still a very affordable fuel compared to electricity. Older water heaters often lasted 20 to 25 years. Unfortunately, our newer replacements have on average 6-year pro-rated warranties and may not be manufactured to last much more than the warranty period. Energy efficiency is usually from 53% to about 62%, which means up to 47% of energy goes up in smoke. Energy Star conventional gas tank water heaters are a minimum of 67% efficient. These are not so common and can have slightly longer warranties.
Electric tank water heaters have not changed much in decades. Typically, they are 240-volt on a 30-amp circuit. They tend to last longer than the 6-year warranty because they have less stresses than a gas-fired tank water heater. They are about 91% efficient using electricity which is typically 3 times the cost of natural gas. One of their unfortunate traits is that electrical appliances that heat things can easily drive your electric bill up. If you don’t have gas, there is probably not a lot of alternatives other than the water heated listed next.
This is a tank with an electric heat pump unit mounted on top. A heat pump has a compressor just like your refrigerator, and it is basically an air conditioner or refrigerator in reverse. Heat pumps are usually 250% efficient. Yes, 1 kilowatt in and 2.5 kilowatts out—their technology is reliable, and they are regarded as a Green appliance. G.E., Rheem, Kenmore, A.O. Smith are just a few of the models available. If you are forced to have an electric water heater, or you have solar electric and want to conserve, this is a great choice.
Tankless water heaters were invented in 1868 in London. The first tankless water heater was called the “Geyser”. On-demand or tankless water heaters have been used worldwide for decades. Europeans, Asians, and Australasians would be confused if they saw a tank water heater.
The major producers of tankless water heaters in Japan began to tackle the remaining tankless hold outs of the world water heater market in Canada and the US in the late 1990s. High energy costs in other parts of the world would make it prohibitively expensive to use tank water heaters. Gas-fired tankless water heaters range from 84% efficient to 96% efficient. If you convert from a 62% efficient conventional gas water heater to a 96% efficient heater, you could reduce your household energy bill by up to 6%. That could be hundreds of dollars saved per year.
Tankless water heaters are great, but they are not a good fit in all situations. If the house has long pipe runs and does not have a recirculating system, the user can get frustrated with a tankless unit. Retrofitting recirculating systems or on-demand recirculating pumps can be a solution to wasting water in any household and make a tankless water heater user-friendly in a not so well-plumbed house.
Tankless water heaters also require maintenance to ensure they will last a long time. Maintenance is usually needed every 3 years. We have water heaters that are 15 years old and expect them to last 20 years. Some homeowners will buy 3 tank water heaters in 20 years, and not have the energy savings or reliability of a tankless water heater.
The Rinnai RH180 is a 40-gallon storage tank with a tankless water heater attached. It is called the 180 because it produces 180 to 190 gallons of hot water per hour if needed. (a 50-gallon gas water heater normally produces 90 gallons in the first hour). A thermal efficiency of 80% makes it 13% better than the Energy Star minimum standard. It uses a conventional ½” gas line, a conventional 4-inch metal flue, and is a direct replacement of any 40- or 50-gallon conventional gas tank water heater. It works with any piping configuration or long pipe runs in a house. The tankless technology is well-tested and more reliable than the low NOx burners in conventional gas heaters. There is no flame to stress the storage tank which will increase tank life considerably. In the event of a severe earthquake, you would have 40 gallons of fresh drinking water in storage. Installation time is reduced because it is a direct replacement and does not require a separate flue or new gas line or electrical outlet.
The most economical water heater to run is the one that is heated for free by the sun. Solar water heaters have been around for a long time. They were very popular in the 70s with the huge tax credits available. Former mayor Arnold Schwarzenegger re-vamped solar hot water with the California Solar Initiative Thermal Program wherein rebates and tax credits are available for replacing an electric, natural gas, or propane water heater.
Solar water heaters are generally “preheat systems”. The sun slowly heats a storage tank when sunlight is available. The pre-heated water then goes to feed another water heater before it comes to your faucets. In the summer months, the sun can heat 100% of the hot water. In the winter, the solar system partially heats the hot water. When no sun is available, the regular water heater can do 100% of the work. Solar energy systems that feed tankless gas or tankless electric water heaters are a great combination because the tankless is purely on-demand and has no wasted energy when not used.
An indirect tank is a storage tank that is heated usually by your radiant heat boiler. Most modern boilers are 95% efficient and make a very efficient heat source. Indirect tanks are very well insulated and do not lose a lot of heat just storing the hot water. They are typically made of high-quality stainless steel and should last a very long time. The indirect tank has been used in Europe for over 50 years. Indirect tanks are an efficient way to heat hot water and store it.
Water heaters are designed for heating domestic hot water for showering and bathing. Heating Boilers are specifically designed for radiant heating. Boilers are a great investment. They can last 20 to 60 years. Water heaters used for radiant heating often fail in 5 to 6 years because they are not designed for continuous use. Call a licensed Boiler Contractor to take care of your radiant heating needs.
Our philosophy is simple, we always want to maintain equipment to give it the longest life possible. Next, we want to focus on repairing when something goes wrong. Then only as the last choice, we replace equipment when needed. That’s the John Owens Way.