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When we hear the phrase “water heater,” most of us probably get a picture in our heads of the traditional storage water heater. Although many other types of water heaters are now available, the standard storage water heater remains the most commonly seen in homes across the United States. A storage water heater consists of a tank or reservoir that holds water. A pipe brings cold water into the tank, where it is heated. Warm water rises to the top of the tank and is disbursed through another pipe whenever hot water is needed throughout the house. Storage water heaters all do basically the same thing, they just use different sources of energy for heating the water. Let’s take a closer look.

 

STORAGE water heaterBasic Structure

The basic structure of a storage water heater is pretty simple. The visible part — the drum — is a tall cylindrical tank made of heavy metal, a layer of insulation and an outer shell. Tanks hold 30 – 80 gallons of water, depending on size. Cold water enters the tank through the dip tube. The end of the heat-out pipe lies near the top of the tank, ready to whisk heated water wherever it is needed. Other essential parts of each storage water heater are the thermostat, drain valve, pressure relief valve, sacrificial anode rod, and a shut-off valve. The heating mechanisms differ in how they supply the heat needed to warm the water. We’ll look at gas water heaters first.

 

Gas Water Heaters

Gas water heaters, as the name implies, use natural gas or propane to fuel the heat for your water. The heating system for this type water heater has two main parts: the burner and the venting system.

gas water heaterThe Burner

The burner sits beneath the tank in a small chamber. This burner operates on the combustion principle. Gas — either natural gas or liquid propane (LP) flows through a valve into the burner. A thermostat located outside the tank projects a heat sensitive probe inside the tank. The thermostat controls the flow of gas to the burner. Combustion occurs when the pilot light ignites the gas flowing through the burner. Flames heat the bottom of the tank, transferring heat to the water inside the tank. Small openings in the combustion chamber allow air to enter.

As long as gas and air continue to flow into the combustion chamber, the burner will continue to heat water. Thermostats are generally set between 120 to 180 degrees Fahrenheit , although newer models may restrict the upper limit to 150 degrees Fahrenheit. An energy cut off switch acts as a safety mechanism within the thermostat. If the probe detects water temperature above 190 degrees F, the energy cut off valve shuts off the gas flow. If this happens, you usually have to replace the entire gas valve mechanism. The combustion process, though very efficient for heating, produces harmful fumes and requires proper venting.

gas water heaterThe Venting System

Carbon dioxide, carbon monoxide, and nitrogen oxide produced in the combustion process are harmful to breathe. They must be vented outside the home or office to protect the people inside the buildings. Gas storage water heaters use a flue and hood venting system. The flue consists of a bottom hood within the combustion chamber. This hood collects and directs the exhaust fumes up through the flue. The flue itself is a small tube rising through the tank and exiting at the top. Many flues now contain baffles. A baffle is a shaped like a helix. It deflects the exhaust push the heated air to the sides of the flue to help heat the water. Exhaust exits the tank through the draft hood located just above the top of the tank. The draft hood prevents back drafts into the flue and vents noxious gasses outside the home or office.

Electric Water Heaters

storage water heaterElectric storage water heaters have the same basic parts as their gas-fueled cousins. Rather than heating water with fire, though, electric water heaters use electricity. The heating system for an electric water heater also has to main parts: the elements and the circuit control.

The elements

The elements in this system work much like the burners on an electric stove. Elements may be stainless steel or copper-plated. They consist of a wire surrounded by filler material encased in a U-shaped tube of either stainless steel or copper. They project into the tank about one-third down from the top of the tank and one-third up from the bottom. Each element has its own thermostat. As electricity flows through the inner wire, resistance in the wire generates heat. The heat passes into the filler material and outer sheath of the element to heat the water. The upper element operates first to heat the top one-third of the water to the temperature set on the thermostat. Once the upper water has reached this temperature, the lower element comes on and heats the middle third of the water.

The control circuit

storage water heatersThe control circuit includes the elements, thermostats, a high limit control switch, and a reset button. As in the case with the gas-powered water heater, the electric water heater also carefully monitors water temperature and pressure. If water temperature in the electric water heater exceeds the established limit, the high limit switch activates and shuts down the entire unit. You can restart the unit once it cools by pushing the reset button on the thermostat.

which storage water heaterConclusion

Well, there you have it. Although both types of storage water heaters provide the same function, the do so by very different means. When you’re considering a new water heater, be sure you review all your options carefully. Both types of heater have energy efficiency and safety features built in. Just how much money you can save will depend on the needs of your family or business. Give us a call today. We’ll walk you through all the details and help you make the best choice for your particular needs.

Solar water heaters have the potential of being an ecofriendly and cost-efficient way of heating one’s household water supply. The process is simple and does just what the name implies. This type of system harnesses sunlight, turning it into heat through a device called a Solar Thermal Collector.

Direct solar water heater systems

There are several types of solar water heaters on the market. While it’s true that these water heaters can work in any climate, some do work better in warmer areas.

Open loop

One of the most common types of Solar Water Heaters is called a Direct System, also known as an “active” or “open loop”.  The process for the Active system is simple: Water is circulated from the water tank, up to the roof to the Solar Thermal Collectors. The water is then heated in the collectors and transferred down to the water tank and into the household, ready, for use. This type of system is best for tropical climates, as it doesn’t require assistance in heating one’s water.

Closed loop

The most common Solar Water Heater, in the Direct System, is the Indirect or “closed-loop” system. These work best in climates where temperatures drop below freezing. This system uses a combination of sunlight and antifreeze to heat the water. Antifreeze is circulated from the water heater up to the Solar Thermal Collectors, heated, and then moved down into the heat exchanger, heating the water in the tank, indirectly. The cooler antifreeze is then pushed back up to the collectors where the process begins again.

Common Problems with Solar Water Heaters

Leaking

Probably the most common problem with a Solar Water Heater is leaking. The most plausible explanation for this is a leaky temperature and pressure relief valve on the solar heater. Do not try to repair this problem on your own. It’s better to call and have a technician come out and replace it. Another reason leaks can occur is because the piping in the solar panel has burst. This may be due to either freezing weather conditions or simply too much pressure in the pipes. It is best to call a technician to come and assess this problem as well. The problem could also be that the pipe fittings just need to be tightened.

Not enough hot water

The second most common problem is not having enough hot water. To address this issue you can do a couple of things.

Make sure the solar panel is in the correct placement on the roof, i.e. away from tree shading, facing south with the recommended tilt. Also consider if the solar panel size is correct for the household size. The amount of hot water that you use will help determine the size you need. Not having enough hot water can also be caused by a leaky or stuck valve. Make sure that if there is a back up storage tank, that the thermostat is set to the right temperature. Be mindful in the winter months that the solar panel is given an adequate slope, so the output end is higher. There could also be a system blockage. If so, all you need to do is flush the system until the flow is no longer blocked. The most important thing you can do is make sure that the solar panels are properly insulated.

No hot waterno hot water, water heaters

Finally, the third most often reported problem is no hot water at all. To avoid this problem, it is best to be preemptive. Make sure to maintain the absorber paint on the collector panels. If this paint deteriorates, it can cause the system to be less efficient. Make sure that the paint is both heat and UV exposure resistant. Also make sure to provide a small weep hole on the bottom of the collectors. When there is a lot of condensation inside the panels, the excess needs to be expelled so as not to affect the performance of the system.

Conclusion

Despite their drawbacks, Solar Water Heaters are a great option for alternative-energy conscious homeowners. If you are looking to save money, we’ve got everything you need to get you started on this eco-friendly alternative energy option for your home. Give us a call today!

scrabble tiles spell save on top of pile of moneyTankless or demand-type water heaters are a type of water heater that only heats up water when one needs it. They are a more cost-efficient way of heating water because they don’t waste as much energy on heating a whole storage water tank. They are also referred to as instantaneous water heaters.

How do they work?

 

diagram of how tankless water heater works

The way these water heaters are designed is quite ingenious. The hot water is turned on at the tap, and cold water is propelled though the pipeline into the unit. Once this happens, either an electric unit or a gas burner heats the water. This type of system practically insures that one will always have hot water available. It will produce about 2-5 gallons of hot water per minute. Keep in mind that a gas-burning water heater will yield larger quantities of flow rates than an electric-powered water heater. The beauty of this is that the demand-type water heater will do all of this without needing a hot water heating tank, saving space, money, and energy in the process.

While the tankless water heater itself is more expensive than the typical storage water heater, it will usually last longer. Tankless water heaters also cost less to operate, and as mentioned before, save energy. All that counters the initial purchase price. In addition, the storage water heater only lasts about 10-15 years, whereas a tankless water heater will last up to 20. It is also easy to keep up with the maintenance of a tankless water heater because its parts are so easy to come by and usually cheap.

What are some common problems with tankless water heaters?

Running out of hot water

One of the most common problems with a tankless or demand-type water heater is that it runs out of hot water too quickly. There are several variables that one must consider when dealing with this problem. One reason this could be happening is that tankless water heaters cannot supply enough hot water when the hot water is being used for multiple things at the same time. For example, if one household is using the dishwasher, the laundry machine, and the shower all at the same time, this will drastically impede the water heater’s ability to supply hot water to all three places. A simple but slightly pricey solution to this problem is to install an additional tankless water heater next to the original to help spread the hot water throughout the household. Another possibility is to install appliance-specific water heaters onto the appliances.

close-up of blockage in pipeMineral build-up

Mineral build-up can be another culprit. Hard water can be damaging and counter-productive for any water heater. Be sure to flush the tankless water heater about every six months or so to insure optimal usage. Consider a water softener to help keep the mineral build-up to a minimum.

flame lighting matchesFailure to ignite

Failure to ignite is a frustrating problem. This is often caused by blockage of the air supply or exhaust. Many tankless water heaters will have a display with an error code to tell that there is an air supply or exhaust problem. The demand-type water heater is most likely struggling with venting or combustion air. Make sure all the vents are clear. Look out for small animals, birds or even wasps. These creatures like to make their homes in or around the outside vents.

Flame failure

Flame failure is another common problem. This typically occurs from an electrical or gas pressure issue. Make sure that it is not because of an overdue gas bill or empty propane tank before calling professionals.

Sound good?

Give us a call if it’s time to change the way your house heats water! We have professionals standing by to help with the next chapter in your home improvement journey.

Whether your water heater broke or your family is growing, you might just need a new water heater. Choosing a new one doesn’t have to be overwhelming. Just follow these tips, and this will be one of the easiest things you’ve done!

Research How Water Heaters Work

There are a lot of different kinds of water heaters. They range from tank to tankless and can be powered by gas, electricity, oil, solar or heat pump.

graph showing differences between electric and gas water heatersThe two most common tank water heaters run on gas or electricity.

Electric water heaters use coils that go down into the tank to heat your water. This type is ideal for a smaller household that doesn’t require much hot water. Although electric water heaters might be cheaper to purchase, they’re not as efficient as gas heaters in the long run. They also tend to be more expensive over time.

Gas heaters, be it natural gas or propane, are another common water heater choice. They use a gas burner that is vented through a chimney or small wall vent. Propane gas heaters are used when natural gas is not accessible. Propane tends to be cheaper than natural gas.

Above are great examples of tank water heaters, but there is another option: a tankless water heater.

graph of a water heater in a basementAlso known as the “on demand” water heater, it only turns on when you need hot water. There is no holding tank, which makes this a more efficient option. However, like the electric water heater, this also makes it a more expensive option.

You also need to consider the lifetime expectancy of the heater you choose. Where a tank water heater can hold from 40 to 60 gallons of hot water and last up to 13 years, a tankless heater can last up to 20 years.

Taking all this into consideration, it ultimately comes to what is most suitable for you and your household.

Size and Storage Of Water Heaters

You must factor size and storage into your search for a new water heater. To help with this, think back to how satisfied you were with how your old one worked. Some things to consider: Did you had enough hot water? How long did you have to wait for it to reheat?

graph of water heaters and sizes

If the old water heater didn’t provide enough hot water, you might want to upgrade the size of the new water heater.

For a storage tank water heater, a very important factor to consider is the amount of water that can be held and the recovery rate, which is basically the amount of water that can be heated in an hour. An energy sticker on the new water heater will display the recovery rate as First Hour Rating (FHR).

For example, a four-person household would require a 40- to 50-gallon water tank, whereas a two-person household could skate by with a 30- to 40-gallon tank.

Gas heaters have a better FHR than electric water heaters, which means they have a smaller tank with the same EF rating.

Now What?

Choosing your new water heater doesn’t have to be a headache. Just remember: do your research on types, sizes and storage options.

If you get stuck, give us a call. Here at Knoxville Plumbing, we have experts who can help you evaluate what your family needs and match these up with the heater that will work best for you and your household.

frustrated kid holding his headIt can be very frustrating trying to figure out if it’s time to replace the household water heater, or if it simply needs a little TLC. This article will help shed some light on whether it just needs a repair, or if it needs to be replaced.

There are plenty of signs that a water heater is about to fail. Below are some of the most common indications that it’s time to replace the household water heater. 

Common Signs It’s Time To Replace the Water Heater

rust-colored water running out of a faucet

If the water heater is 10 years or older, it will be in the best interest of the house to go ahead and replace it before it starts causing problems. To check the age of the water heater, simply look on the upper part of it and find the manufacturer’s sticker.

If rust-colored, metallic tasting water is coming out of the hot water faucet, this is another big indicator. Dark, metallic water is a clear sign that the inside of the water heater is beginning to rust. If this is left unattended for too long, it will severely damage the tank. It will also begin to leak and cause more damage to the home. 

sediment at bottom of a water heaterWith older water heaters, it is not uncommon to notice strange noises or rumbling coming from the unit. These are usually caused by excessive sediment build-up accumulating on the bottom of the water heater. As the water heater will frequently change temperature, the sediment will eventually harden. When this happens, it will be harder for the water heater to effectively heat the household water supply. This will ultimately cost more money to run it. 

leak underneath water heaterConsistent “puddles” around the base of the water heater could be a sign that there are fissures and cracks in the hull of the tank. As the metal heats and expands and then cools and shrinks again, this causes these fissures and cracks. While this is normal and should not cause problems for quite some time, in an older water heater it could be a sign that it is time to replace the water heater. But before doing that, make sure that leaky pipes or loose valves are not to blame.

Why Isn’t There Enough Hot Water? 

shivering duckIt’s safe to assume that the biggest problem with water heaters is that there is often not enough hot water being supplied to the household. There are some simple explanations as to why this is happening, regardless of the type of water heater (i.e. gas or electric).

Electric Water Heater Malfunctions and Possible Causes 

yellow lightning boltMake sure that the water heater has a proper connection to the power source, and then, reset the thermostat. There could also be too much sediment in the bottom. As mentioned above, this impedes the function and makes it harder to heat enough amounts of water. A good flushing of the water tank will make sure that all the sediment is removed.

Another culprit might be that the pipes are not properly insulated, and the water is losing heat on its way up to the rest of the household. Another thing to assess is the heating element or thermostat. If this is the case, it would be best to just replace that part, rather than the entire unit. If all those things check out fine, it could just be as easy as raising the temperature.

Gas Water Heater Malfunctions and Possible Causes

close up of water heaterThere are only a few differences when it comes to assessing problems with electric and gas water heaters. The first thing to check on a gas model is the pilot light. If the pilot light has gone out, relight it, and make sure that the gas valve is hooked up securely and properly. Another issue could be that the gas burner needs to be cleaned. The cleaning is a good time to go ahead and replace the thermocouple, too. Just like electric versions, it is important to flush to rid the tank of sediment. Also, keep an eye out for rusty water coming from the hot water faucet.

In conclusion, if the tank itself is presenting serious damage signs, it is smartest to replace the whole water heater. Give us a call, and we will be more than happy to help you make the right decision!