Tankless Hot Water Heater will provide hot water immediately without the use of the enormous amount of energy it takes to heat a big storage tank. They fit into our vision of an eco-friendly home. Although installing a gas Tankless Hot Water Heater may be a bit more time consuming than installing an electric one, both processes are relatively easy with proper preparation.
Installing a Gas Tankless Hot Water Heater
The beauty of a Tankless Hot Water Heater is it's a wonderful way to reduce energy cost, and it is not bulky like old school water storage tanks. These heaters don't lose standby heat like most storage heater, and gas driven tankless heaters have flow rates that are higher than do the electric ones. We are going to learn how to install a gas Tankless Hot Water Heater but first a safety note.
CSST (corrugated stainless steel tubing) is the flexible gas supply line for this installation. Be on guard for lightning strikes that could create arcing between the metal conductors near the CSST causing the flexible line to rupture. Therefore, all installations with CSST must be bonded directly using heavy gauge wire in order to conduct electrical energy safely to ground which significantly reduces the threat of arcing.
If we don't have one, we need a supply gas line installed for the Tankless Hot Water Heater. To do this, in the existing gas line place a T and valve and run a corrugated stainless steel supply line for the heater. The inside diameter of one quarter inch is the minimum gas line size. Tankless water heaters run on higher BTUs in order to run more efficiently and to heat water quickly. The heater doesn't use more gas but requires a greater gas jolt.
Next, we have to mount the copper waterline for the Tankless Hot Water Heater. There are brackets that will hold the pipes steady and prevent them from wall contact as well as to aid in applying the pipe insulation. Before soldering, clean pipe copper joints thoroughly and coat with flux. Now we can tie in new copper waterlines for the tankless heater.
We need a platform that is covered to position the Tankless Hot Water Heater so the tank's vent clears the joints on the floor when passing through the walls located on the outside. The platform needs to be secured with concrete screws.
Place the Tankless Hot Water Heater on the platform and secure it with a screw through the mounting bracket and into the platform.
With an adjustable wrench connect gas shut off valve, supply line and sediment trap. Follow this by connecting them to the stainless steel corrugated supply line. Tighten up with an adjustable wrench.
Use the bell hangers to support pipe runs after making connections between the tankless water heat and the water shutoff valves. Follow this by soldering the joints on the piping making sure the joints are secure.
Bleed the air from the line after turning on the gas and run a gas sniffing device at every joint to check for gas leaks.
We are now ready to apply silicon sealant to the vent's heater and place a connector securing it with a hose clamp. Continue by adding secure sections of elbows and vent pipe and drill through the center of the vent hole to the outside wall. Attach heater
We can now install the metal wall thimble through the wall by tracing the thimble and cutting the outside wall away. The thimble should rest against the sheathing of the wall. Exterior and interior portions of the thimble can now be installed and remaining pieces of the vent piping can be added.
Time to plug in the unit to generate power to the thermostat and microprocessor. We also need to insulate the hot water pipes with pipe insulation. Plug Electric Power to the Tankless Hot Water Heater and Insulate Pipes. Turn on the gas, press start and voilà, we have hot water!
Electric Tankless Hot Water Heater
One benefit of installing an electric Tankless Hot Water Heater is safety. Tne chances of an explosion caused by a gas leak are far greater than faulty wiring to the tank causing electrocution. Safety: Your chances of an explosion from a gas leak are much greater than electrocution from faulty wiring to your tank. Plus, the damage to your home after an explosion far exceeds most damage that an electric tank could do.
As noted above, installing an electric Tankless Hot Water Heater is easy and can be done by most of us in less than ten minutes by following these easy steps.
- Consider an installation location for the electric Tankless Hot Water Heater close to existing main electrical panel and existing configurations of plumbing like kitchen, bathroom, etc. Make sure the heater is in an easy access location and is physically near the faucets most often used. This allows hot water to travel to applications faster.
- Secure your electric Tankless Hot Water Heater to a mounting surface with screws using mounting brackets usually provided in the purchased package. Be sure the surface you are mounting on is secure and solid to ensure a level unit. Install the unit in an upright position with outlet and inlet connections for water at the heater's bottom. This heater should be installed in a upright position with the inlet and outlet water connections at the bottom of the unit.
- The hot water pipe and water heater needs to be at a minimum 25 inches away from any combustible material.
- When installing a tankless electric water heater, follow national and local electrical codes because these units need a higher voltage power supply and a wall outlet that is properly grounded and the voltage must match the rating plate.
- All hot water pipes should be insulated to minimize energy loss. Now we are ready to enjoy hot water the Eco-friendly way.
Advantages Of A Tankless Water Heater
Most of us have probably considered replacing our old hot water tank with a tankless hot water heater. An “on demand” water heating unit may sound like a novel idea that probably doesn't work as well as a good old fashion tank but it does. That's why many homeowners like us have made the switch and here are some reasons why.
Tankless hot water heaters take up much less space than does the conventional hot water tank. They are compact with a typical size of about 20 inches by 12 inches by 3 inches. This frees up a lot of room in our homes that can be used for other reasons. It's even a better idea if the space we are living in is small. Traditional tank heaters hold between 40 to 60 gallons of water and are approximately five feet tall and two feet round. The tankless water heater takes up about as much space as a computer used in the home. A small tankless water heater can fit in a small space and be much less obtrusive than a big tank. They can be mounted on a wall in the basement or some other unobtrusive place. For small homes, this is a truly welcomed benefit.
Safety is another reason that comes as a benefit of choosing a tankless hot water heater. Because the tankless water heater is small, there is little chance of getting burned since hot water is not stored in the tank and is processed only when needed. There is no need to worry about an explosion or an accident which could spew tons of scalding water everywhere harming our families, our pets and our furnishings. Plus, children will not be tempted to turn the tap on the conventional tank, which could be an accident just waiting to happen.
A safe setting which is standard for a tankless hot water heater is 122 degrees, and many systems have thermostats that are computer controlled and keep a safe setting consistently. They also utilize a computerized monitoring system and controls that are adjustable and are self monitored, so we don't have to constantly check the settings. Information like flow rate and temperature settings are displayed on LED readout panels.
- Cost efficient
Reason three is significant because using a Tankless Hot Water Heater offers a 50% reduction in heating costs as opposed to using a hot water tank. Hot water tanks often undergo what is known as standby losses, where heat has evaporated through the sides or the flue and adds an unwanted expense to a bill. In addition, tankless hot water systems don't leak like conventional tanks can. This also runs up a utility bill because of maintenance and drips. Plus, the tankless heater obviously doesn't have a tank that could potentially run out of water.
The water supply from a tankless hot water heater is endless. This means we will never have to wait for a hot shower or bath. The unit runs at about 200,000 btu's per hour allowing for plenty of hot water for three or more showers without running out of hot water.
They also qualify for financing through PACE. The purchase and financing can be done by the homeowner contacting a local PACE program and pay for the tankless upgrade over a time period and add as an item on annual property tax bill. For those of us on a budget, this comes as a welcome benefit.
Last but not least, the life expectancy of a tankless water heater is approximately 20 year. The conventional water heater has a life expectancy of 10 to 15 years. Unlike a tankless heater, when a conventional tank fails, there is no option but to replace it. The warranty on a tankless heater usually covers the heat exchange and parts. Most brands cover the heat exchange for 10 years and parts for up to five years.
Generally, manufactures will guarantee their warranties for half of the heater's life expectancy, which is the case for most electrical appliances. Again, the advantage is a tankless system has replaceable parts. Should the heat exchange breaks after the warranty period ends, a new exchanger can be purchased.
Note that the type of water that is flowing through our tankless system will play a role in its life expectancy. If the water is too acidic, there is a good chance that it will erode the heat exchange and pipes that are part of the unit. Any acidic water should be treated with a water softener and any scale build up should be removed by flushing out the system. The system should be flushed out about every six months to keep it clean and free of calcium and mineral deposits. if not, we may need to replace the tankless heater, or the very least, the heat exchange sooner than we would like.
Tankless Hot Water Heater With Or Without a Water Tank – Our Thoughts
We have to make a decision, and there is a lot to consider. Should we go with a conventional hot water tank or should we try out a tankless hot water heater? If we think about the last time our conventional tank leaked all over the floor and had to be replaced to the hefty tune of $600 or more (not including installation), we might lean towards a tankless unit. On the other hand, if we are a family of five or more who tend to take showers one right after the other, more than one tankless unit may be needed.
If the expense of purchasing and installing more than one tankless hot water heater is more than our budget can handle, a large hot water tank just might be the way to go. There's a lot to consider when trying to decide. Let's start with price comparisons. Depending on the size we need has a lot to do in determining the price, as does the type and brand we choose, as well as the model we choose and whether it is electric or gas or tank or tankless.
Most units with tanks fall somewhere between $500 to $600. Although some can run over $1000. Electric water heaters with tanks run a bit higher. Tankless electric units average between $600 to $800, while gas tankless run on the average around $900. As with tank units, some tankless can run over $1000.
We know that a tankless heater doesn't store hot water and uses water when needed. So we realize that this is a plus because the tankless uses less energy, and we save money in the long run. As mentioned, depending on the factors listed above, both tank and tankless prices range from around $500 to over $1,000.
However, there are more choices available when selecting a hot water heater with a tank. The short of it is any water heater is a somewhat costly investment for us, and we have to live with it for a long time, so we have to consider longevity, efficiency and cost when choosing a new water heater.
We need to do our homework to decide which hot water heater will best fit our needs. Whatever one we choose has to provide enough hot water for the number of people we are providing for. If the choice is a water heater with a tank, check the old one to be sure the new one is the same height and size that provides an adequate supply of hot water. If we find that the hot water runs out too quickly, we may need to consider a larger tank. Also decide whether the tank runs by gas or electric.
Traditional Tank Storage Water Heaters
Storage tank heaters are often found in homes often times in the basement. They are made up of an insulated tank that holds between 30 to 50 gallons of water and heats until water is required. There's a pipe at the top of the unit that delivers hot water to sinks, bathtubs, washing machines, dishwashers, etc. throughout the house.
They use either electricity or natural gas to power them. The natural gas heater are more efficient using less power to operate and are more expensive than their electric heater sisters. Gas heaters also have a temperature/pressure release valve that opens when the pressure or temperature goes above the preset level.
Electric hot water heaters with tanks have, in the past, most often used when gas is unavailable. The reason is they are not nearly as economical as gas hot water heaters. Even with a high efficiency heater, the high cost of electricity can't compete with a gas driven unit.
If we do go with electric, we need to consider these factors:
- Energy factor tell us the efficiency of the heater converting hot water via electricity. The greater the energy factor, the better the heater.
- Capacity needs to be in concert with our home's demands for hot water.
Tankless water heaters heat water directly without the use of a storage tank. When a hot water tap is turned on, cold water travels through a pipe into the unit. Either a gas burner or an electric element heats the water. As a result, tankless water heaters deliver a constant supply of hot water. We know that tankless heaters are more efficient because heat is not lost by water cooled down in a tank and then reheated. However, a tankless hot water heater has to have a capacity to meet needs through a temperature rise specification, which is degrees displaying the amount of heat generated at gallons per hour flow rate.
In other words, if the cold water flowing into the heater is 50 degrees, and we need it to be 75 degrees, the gallons per hour flow rate must be sufficient to meet household demands. As noted, if our hot water demands at any time exceed the unit's flow, we may have to install more than one unit to compensate and up the flow. The good news is, this will probably provide a longer life for each unit.
Like everything else, there are pros and cons when it comes to deciding on a conventional hot water tank heater or a tankless hot water heater. One common thread is they will both heat your water, but the tankless unit takes up less space and lasts ten plus years longer than the tank. Since the prices are comparable, it comes down to deciding what best fits our needs that that of our families.
How Does A Tankless Water Heater Work?
To understand how a tankless hot water heater works we need to recap how a standard tank heater works. There is a large tank filled with heated water. The tank heats the water on an ongoing basis to keep it at a sustained temperature and ready to provide hot water when we need it. The energy it takes to keep water hot consistently is known as “standby loss of heat.
Contrary to a tank water heater, the tankless system bypasses standby loss by providing on demand water or water is heated when it is needed. That's why many consider tankless hot water heaters more efficient and economical.
In making the decision to go with a tankless heater we must figure out the amount of water we need at any given time. We should also know the difference between the desired hot water temperature we want as opposed to the groundwater temperature. As an example, if our home is in Atlanta, ground water is around 62 degrees F. In order to reach a hot water temperature of 120 degrees F, we need to subtract 62 away from 120. This gives us a the 58 degree F required.
Whole-home gas tankless water heaters utilize the same principle to heat water as do standard gas water heaters, but without a storage tank. They conserve energy by heating water when needed, eliminating energy lost during standby operation. When a hot water faucet is turned on in the home, cold water is drawn into the water heater.
A flow sensor activates the gas burner, which warms the heat exchanger. Incoming cold water surrounds the heat exchanger and leaves the heater at its set-point temperature. Combustion gases safely leave through a dedicated, sealed vent system. By heating water only when needed, instead of maintaining a full tank of warm water all the time, Tankless Hot Water Heater do achieve greater efficiency than standard tank-type water heaters.
Gas Driven Tankless Hot Water Heater
It is recommended that when choosing a gas tankless system we go with an Energy Star certified unit because it uses a heat exchanger which is secondary and uses nine percent less energy than a conventional gas tankless model. More heat from combustion gas is extracted from the heat exchanger and cools it until there is condensation. Therefore these heaters are known as “gas condensing“. They require vertical PVC pipes as well as a condensate drain for venting. Investing in the drain and PVC pipes will pay off in the long run.
The gas burner supplies heat to the exchanger which allows water to pass in a serpentine pattern. This allows heat to be absorbed by the water from the heat exchanger's walls. As noted, some gas tankless use a secondary heat exchanger that uses heat from exhaust gases from the burner to pre-heat water. Most gas tankless come with pre set maximum temperatures to prevent scalding.
As temperature and flow rate can vary, there is a modulator than controls the amount of gas entering the burner, raising or lowering it as necessary. This is what keeps a set temperature for the water based on a water temperature sensor that is on the heat exchanger's exit side. The sparking ignitor is powered to our power supply.
How An Electric Tankless Hot Water Heater Works
We've discussed “on demand” when we talk about electric systems, which is cold water entering one side of the heater that is instantly heat and leaves from the other side passing through pipes as it departs. Most owners prefer to install tankless electric units close to where they are being used in order to reduce water travel time going through pipes enabling hot water faster. There is no cycling or stand by loss because the hot water comes on demand which reduces heating expenses as well.
The elements included in an electric tankless unit consists of coils that heat up the water flowing through. A power switch applies electrical current directly to the coils when hot water is required. When not in use, there is no current present. A factory set microprocessor can maintain a constant output temperature even if low rates vary.
The electric tankless hot water tank can be point of use or whole house heaters. The point of use systems are small and only heat water for one or two outlets like a shower and sink. They easily fit in a closet or under a cabinet.
They are often installed near the outlet we need it for to avoid lag time of hot water flow. Some people choose to install more than one electric unit. Whole house systems are much larger than point of use and operate more outlets at the same time. Obviously, they are more expensive than point of use, but are certainly more practical for large families.
Problems That Might Occur Using a Tankless Gas Heater
Although they do not happen often, problems can happen with an electric or gas tankless hot water heater. Here are some issues and concerns that have occurred with gas tankless.
- Flame failure message
- Air supply of exhaust blockage
- Mineral Buildup
- System Overload
- Cold Water Sandwich
- Air Supply or Exhaust Blockage Message
- No Ignition Message
A flame failure message alert in a gas tankless indicates there is an electrical problem or a gas pressure problem. It could be because of gas pressure. In addition, no ignition messages could be an indication that there may be a low propane tank level (if propane is used) or a gas bill that has not been paid. If these two reasons do not apply, it could be one of several factors creating a problem with gas pressure. For instance, the gas line could be too small, issues with combustion, regulator failure venting, etc.
It's probably time to call a technician who specializes in tankless heaters to check out the problem using a manometer to measure the gas pressure and identify the problem. If the gas pressure isn't the problem, the flame failure could be related to an electrical issue that should also be handled by a knowledgeable technician.
Mineral buildup is a serious problem because it could ruin the water heater. The water in the unit should be flushed every six months with a flushing system and descaling cleaning kit. It would be wise to add water softener to slow down the buildup. Hard water, as opposed to soft water, has a very high mineral content and the harder the water is, there is a higher likelihood for mineral buildup damage. Magnesium and calcium are the two culprits that can cause scaly accumulation which can cause trouble in the way the unit functions.
If there are too many hot water applications running simultaneously like dishwasher, washing machine and shower running at once, the water heater can be overloaded causing a system overload. It can't easily supply the hot water necessary and may shut down if it becomes overloaded. To fix this, we must reduce the hot water demand by eliminating running applications simultaneously.
We might also need to consider upgrading to a higher capacity unit or adding one or more units to our home. This is an additional expense, but in the long run we will save money using less water while we wait for hot water.
A Cold Water Sandwich may sound funny but it's not funny if we are the last one in the family to take a shower. We're the one who jumps in the shower and after a brief splash of warm water are greeted with a blast of cold water lasting several seconds before the water warms up again.
Simplicity tells us that after the first shower came to an end, there still warm water trapped in the pipes leading to the shower. That trapped water is what we first feel when it's our turn for a shower. Even on demand tankless heater need time to heat water. When the trapped water is gone, there's a short gap of cold water before hot water flows from the heater to the shower head. Not much can be done about it but at least we know why.
If exhaust or air supply is blocked it could be combustion air or venting problems. Make sure there are no holes in the vent pipe or the pipes are not properly connected. It could also be animals building nests causing a clogged exhaust. If it's not obvious, the nests could be in the fan motor or in another area that if hard to check.
None of us want to see an ignition failure message, but this doesn't have to be fatal. It could simply mean that the gas supply is low is propane is used. If the water and gas valve are not fully opened, this could be another cause for ignition failure. Water and gas valves should be fully engaged. A more serious cause could be ignition pack failure or something more serious. It's time to call in a professional to help trouble shoot and provide replacement parts if needed.
Common Electric Tankless Water Heater Problems
An electric tankless hot water tank is an investment, and general preventative care and routine maintenance will almost guarantee the 20 year life expectancy of the unit.
Water heater elements have a limited working life. To satisfy hot water needs, continuous cycling can wear the element out as can mineral deposits in the water. The heating cycle of the unit causes minerals that are dissolved to solidify and coat the element acting like insulation. This forces the element to work much harder and sooner or later cause it to fail. If we turn off the power and drain the heater every other month, it helps get rid of sediment and adds longevity to the element's life.
Water heater elements must always be immersed in water because they generate heat that could burn through the copper core in less than a minute if the heat doesn't transfer to water. If the hot water system is not bled when the tank is filled, air pockets can happen allowing the upper element to burn because it's not covered in water. This will cause failure of the element.
Electricity is fed to the elements with heavy gauge wires. Wires that have come off a terminal or a poor connection can stop an element from working. This could also cause a hot wire grounding through the metal on the tank.
The thermostat aids in regulating an element heating water, and this is based on a set temperature level. Should this level deviate, there is a high limit switch that will shut down the power to the element when the temperature is above normal. The thermostat has a reset button that will restore the electricity flow. A technician will need to find out why the high limit switch activated.