Selecting a Replacement Water Heater
How long will the water heater last?
Water heaters have several factors which determine their life. Most tanks are steel with a glass coating. The glass protects the untreated steel from corrosion. The main problems in tanks occur when the glass coating starts to come off the tank. This is caused by several factors but one being that the tank is welded and every time the heater goes through a heating cycle from hot to cold, the welds expand and contract. Eventually weakening the heater and chipping the glass protectant. Heaters can also fail prematurely from high water pressure in the house. The high pressure can be caused by a water pressure regulator failure or no thermal expansion protection. According to the insurance company, the average life of a tank water heater is 8 to 10 years. However, you will commonly see water heaters 18-25 years old. Personally, I believe if the water heater is in a location where water damage is not an issue, the tank is not warping and the heater is not a fire hazard, I would leave the heater until it leaks. If the heater is in a finished basement or in the attic, I would suggest a regular replacement plan.
How much more energy efficient are the new gas natural venting water heaters?
Generally the efficiencies range from .58-.64. Therefore, there realy is minimally energy saving between the new models. Older models were slightly less efficient due to less insulation in the jacket. Typically the models that are at the top end of efficiency are very expensive and have intricate temperature controls. Natural vent heaters exhaust flue gases from the process of hot air rising, more restriction in the hot air rising increases heat transfer, however, the gases can get slow that they won’t leave your house and will stop rising. Once too much heat is transferred the hot air stops rising. New power vent heaters contain a blower which pushes the air out of the house and show some high efficiency. The downside of power vent heaters is the installation cost and cost of the unit.
What about extended warranties?
Extended warranties can be tricky. Some box lot retailers prorate the heater based on life, so that if you have a leak in the last 4 years, you get almost no reimbursement. So the compensation they give you is almost the difference you pay for the extra warranty or less, that way they don’t lose. Rheem hot water heaters extended warranty heaters are good because they actually come with another protective anode rod, the anode rod protects the heater from free electrons which corrode the tank. Rheem gives a full replacement on the water heater if it leaks during warranty versus a prorating.
What’s the best water heater brand?
I am slightly partial to Rheem water heaters but State, AO Smith and Bradford White are good brands. My purchasing decision would be based on track record of the water heater, availability of parts, price, and warranty. I am not a promoter of rare energy efficient models of water heaters shipped in from the west coast. The cost initial cost is high, the actual saving for energy won’t be realized till the heater has been in service for 10 year and is ready for replacement (of course this could change if energy prices spiked), the repair parts are not available locally and the configuration to the existing system will need to be drastically changed.
Selecting Your Water Heater
They are several reasons to replace a water heater: Age, leaking, fire risk, not enough hot water. Typically water heaters are easiest to go bath with a like size and capacity in gallons. Changing from a gas to electric or vice versa can be costly or impossible. Frequently, upsizing from a 40 gallon gas to a 50 gallon gas can be done with little or no issues because the BTU inputs are the same. Larger tanks or multiple tanks can lead to improperly sized flue sizing. Location of the water heater is also important due to required air space gaps and combustion gas requirements and physical limitations of the room.
Is a tank less water heater a cure all to my water heater needs?
Tankless water heaters are great new technology which save some energy, save space and provide endless hot water. However, they are not trouble free. Tankless heaters have control valves, circuit boards, springs, inlet filters, welded heat exchangers subject to expansion stresses and are typically very expensive initially to install versus a typical tank heater. Tankless technology is improving year but do not plan on installing a tankless heater and not having to clean an inlet filter, remove scale from the heat exchanger or needing a plumber to service the gas and temperature control.
Why do new tank water heaters cost more than the old tank water heaters?
Simply the new heaters are slightly more efficient with more slightly more insulation and the new gas water heaters are explosion proof. Explosion proof water heaters or flammable vapor ignition resistant (FVIR), were required by the federal government to prevent explosions related to flammable products like gasoline. The old heater design, if gasoline was spilled on the heater would allow for an explosion to leave the water heater. The new FVIR heater draws air from the bottom of the heater and has a sealed combustion chamber that prevents flames from leaving the heater. Since the new heater is explosion proof the new heater is designed to sit on the floor in a garage or storage space (where the old heater needed to be elevated 18” to protect the heater from flammable gases).
What is thermal expansion and why do I need a thermal expansion tank?
Thermal expansion is a process caused when a material or fluid is heated. Thermal expansion in a water heater is when the temperature of the water is raised, the volume of water increases. Thermal expansion is more a problem now (then 10 years ago) because the federal government has required the counties to install check valves on all the water meters to prevent backflow and contamination into the public system. Check valves at the meter create a closed system on the internal plumbing, so as the water is heated in the water heater the water pressure increases since it can no longer push backwards through the water meter. High water pressure in the house can cause pipes to leak, toilets to run, faucets to explode, noisy or banging pipes, water heater tank failure and emergency relief valve discharge. A thermal expansion tank is a metal tank with a pressured rubber bladder full of air inside. The expansion tank connects to the cold piping on the water heater. When the water heater starts to heat the water, the extra volume of water is pushed into the tank, the air in the bladder compresses and the pressure in the house stays constant. Air is a compressible, water is not compressible. Two allowable alternatives to expansion tanks are a pressure relief ballcock or a separate cold water pressure relief on the cold system, these two alternatives allow water to drain from the system during every heating cycle.
If you would like an estimate on replacing an existing water heater or have any water heater questions, you can contact me with the following information.
Michael Whitman
Atlantis Plumbing
www.atlantisplumbing.com
Phone: 770-505-8570
Email: AtlantaPlumber@yahoo.com
