FROZEN TOES - Breathes there a
person with soul so dead who never to himself (or herself has said) - "Good
grief that water is cold!" (language cleaned up to protect the innocent). Since
most of us don't belong to the Polar Bear Club that blast of cold water as you
first turn on the shower is enough to shatter the firm resolve of even the
strongest will. All of which brings us directly to the subject of water heaters.
The gas or electric tank water heater you are used to has been in our midst
since the early part of the twentieth century and has had little change for 25
or 30 years. The first one I remember was about the size of an oversized
canister vacuum sweeper and was made by RUDD. I won't say how long ago that was.
THE SIMPLE FUNCTION OF A WATER HEATER -
Most current units have elements at the top and bottom. One of them
cycles on or off constantly which increases your heating bill. We all like to
have all the hot water we want the moment we want it. For that reason most of us
have our heater's temperature set on "molten lava" which is both dangerous and
costly. Turning on the hot water causes cold water to be added to the bottom of
the tank which lowers the temperature in the tank. The element turns on to
reheat the water which, of course, uses more electricity. When you are ready for
your bath or shower you adjust the faucet to get the water to a suitable
temperature which usually results in a lot of wasted water. A 60 gallon tank has
45 gallons of useable hot water. There is a "stand-by" heat loss associated with
this. Thus, conventional tanks are constantly losing heat through radiation.
HOW DO YOU GET INSTANT HOW WATER AND STOP WASTING
ENERGY? The solution is to install a tankless water heater. It's a
compact heating unit that provides hot water on demand. For this reason you will
also hear it called an "on demand" system. Unlike a traditional tank type water
heater it does not store hot water. In this system when you open a hot water tap
water enters the heater, the system senses the demand and an electric or gas
heating device heats and delivers hot water at the predetermined temperature.
The system has an electronic ignition system. This eliminates the need for a
pilot light. When the water flow stops the heating element shuts off. The
tankless heaters are energy and money savers since they only use energy to heat
water as it is used. Savings are estimated to be 20% to 40% of the energy used
to heat the water and
NOT of the entire energy bill. None-the-less, on an
annual basis that can amount to a tidy sum; especially in these days of high
energy costs.
WHEN SHOULD YOU CONSIDER A TANKLESS WATER SYSTEM AND WHAT DO THEY
COST? Whether you are interested in a tankless system in order to
save on your energy bill, because you are building a new home and have an option
as to the kind of hot water system to be used or because your existing tank
isn't cranking out hot water as quickly as you want or is showing signs of going
to that old water tank junk yard in the sky, the time to think about it and
consider all the ramifications of installing one is well before it
has to be done. If you would be changing to a
tankless system from an existing tank type system there will be plumbing
modifications required and you may want a separate tank to hold more water as
well. These systems are more limited in the amount of hot water they can produce
at one time than regular systems. Also, they cost 2 to 2 ½ times as much as a
conventional tank type system. While energy saving should eventually pay for the
difference the up front cost is a consideration most people can't afford to
ignore. Furthermore, since these systems don't start heating water until it is
called for it can take longer for it to be delivered. Fear not! For every
problem there is usually a solution. In this case it takes the form of a special
pump. The pump helps the system get hot water to you in about half the time it
takes a normal system to do it. Keep in mind that installing a tankless hot
water system and recirulating pump takes time and you will probably need some
permits and/or licenses prior to starting the job.
ANOTHER ADVANTAGE OF VALUE With a tankless hot water
system you don't have to worry about a water tank leaking or breaking and
causing damage to your home. If this happens when the tank is on the second
floor or attic of a home the damage can be very substantial.
KINDS OF TANKLESS HOT WATER SYSTEMS Basically, there
are two kinds of tankless hot water heater systems: Whole-House and
Point-Of-Use. The whole house system produces from 2 to 5 gallons of hot water
per minute and distributes it to the entire home from a central location.
Point-of-use systems heat water for only one or two fixtures. These heaters are
used when hot water is needed at a considerable distance from the central system
such as a guest house sink or shower. A standard tank heater's average life is
about ten years while a tankless system can last twice as long - with proper
maintenance of course. While these system are relatively new in the U.S. they
have been in use in Europe for many years.
TYPES OF TANKLESS HOT WATER SYSTEMS The types of
tankless hot water systems are natural gas, electric and propane gas. Most of
what you read and hear about electric models is that they take longer to heat
water than their natural gas and propane gas counterparts and use more energy to
do it. To quote from a Rinnai, a manufacturer of natural gas and propane units,
"Electric tankless water heaters can only produce a relatively small amount of
hot water. This is because they require a large amount of electrical current to
produce a significant amount of hot water. For example, in order to have the
same capacity as our smallest unit you would need to provide about 120 amps of
power to an electric tankless unit. This represents over half of the amperage
capacity of a typical home and 5 times the amperage of a typical central air
conditioning unit." Some sources refute the superiority of gas units and later
on I will suggest a source you might want to read concerning this. Of course, if
your home or area does not have natural gas available to it and/or there is
difficulty in getting and maintaining propane tanks that becomes a moot point.
None-the-less, I suggest that you check the ratings of electric units to see how
much hot water per minute they produce and determine how much water is used at
any one time in your home. The "down and dirty" on propane units is that they
are efficient and heat quickly. Propane is stored in a tank on your lot and is
not piped into your home.
To assure proper combustion and to properly vent combustion gases out of a
home, for natural gas and propane units, a good air supply is needed. Many
manufacturers offer units that use the combustion air that is in the home.
Others, such as Rinnai, don't think that is the way to go. They feel that
tankless water heaters have a large gas capacity and need a lot of combustion
air and that most homes don't have the free space needed to install a tankless
system to code. Rinnai says, "Even if you do have the huge open space necessary
to install a system with interior combustion air, that unit will be drawing
thousands of cubic feet of conditioned air from inside your home each day and
will discharge it outdoors. To replace this, outdoor air will be drawn back into
your home through infiltration and will need to be warmed or cooled by your HVAC
system. To us, this is an unacceptable waste of energy." The Rinnai interior
units are sealed combustion and they utilize what is called a power draft
system. Their pipe within a pipe concentric vent sucks in combustion air from
outside and expels the flue gas back outside through a single penetration in the
roof or a wall. This system is exclusive to Rinnai. Furthermore, the tankless
water system heating vent system is cool to the touch.
Since the vast majority of water heaters are placed within the home it is
hard to think in terms of systems that can be mounted outside. Again, material
from Rinnai addresses this when it says that their unit is designed to operate
properly down to outdoor temperatures of minus 30 degrees - F. They go on to say
that exterior units will not freeze up as long as they have electrical power and
gas. However the water connection to an exterior unit must be properly insulated
to prevent them from freezing.
To determine what kind of unit you might want to use I would suggest that you
talk to a building or plumbing contractor. Above I mentioned that electric units
take longer to heat and that not everyone agrees with that. I would point you to
an article by David Seitz that's called - THE GUIDE TO TANKLESS WATER HEATERS.
He makes a case for electric units rather than gas units and his credentials are
substantial. To find it go to Google and type in - tankless water heaters. You
can find it from there.
LOCAL AND NATIONAL LONG RANGE BENEFITS OF USING TANKLESS HOT WATER
SYSTEMS More than 7 million tank water heaters are hauled to
landfills around the nation every year. A switch to tankless systems would be a
substantial help to landfill managers and the number of landfills needed.
Finding places for landfills is a very difficult problem for many communities.
Any major items that are put in them that can be eliminated, or at least
substantially reduced, is of major benefit to them and, in the long run, to you
as well. Switching totally to tankless systems in this country would also
produce annual savings of 290 millions gallons of fuel oil, 6 billion hours of
kilowatt electricity and 164 million gallons of propane.
WHERE DO YOU PUT TANKLESS HOT WATER HEATERS AND WHAT SIZE ARE
THEY? They can be installed in a laundry room, a garage or just
about anywhere that's convenient - including, as just mentioned, outside. For
quicker and better distribution of the heated water, when mounted inside, a
location in the central part of a basement or crawl space is preferable. A
regular 40 gallon hot water heater tank is about 20" in diameter is about 47"
high and weighs in at about 250 pounds. A wall mounted Rinnai tankless hot water
system (for example) is 14" x 24" x 9" and weighs 46 pounds. It has a digital
control that allows users to select the desired water temperature. If you want
to change the temperature from wherever you are in the home you can use wireless
or wall-mounted digital controllers.
DETERMINING YOUR NEEDS AND THE UNIT YOU SHOULD USE
Chili Pepper Appliances is the source of the following information. May I first
say that the following information is probably only going to be read and/or put
into operation by the kind of person who is handy with tools and enjoys being
"Mr. or Mrs. Fix It." But, whether you go directly to a plumbing contractor or
not it is always good to have an idea of what they are talking about so that you
don't get sold the proverbial "bill of goods" and so that you can ask
intelligent questions and end up with the system that best suits your needs.
Chili Pepper Appliances produces pumps that are used to solve the problem of
water waste cause by letting water run to get the desired hot water. The first
thing they say to do is to list the number of faucets and shower heads you
expect to have open at any given time and add up their flow rates. This equals
the flow rate for the heater. Once you know this, THEN go looking for one that
can produce it or have you plumbing contractor look for it.
Water flow for various faucets and shower heads is - Faucets: 0.75 gallons
(2.84 liters) to 2.5 gallons (9.47 liters) per minute. Low-flow showerheads: 1.2
gallons (4.54 liters) to 2 gallons (7.57 liters) per minute. Standard shower
(thar she blows!) heads: 2.5 gallons (9.46 liters) to 3.5 gallons (13.24 liters)
per minute. Clothes washers and dishwashers: 1 gallon (3.79 liters) to 2 gallons
(7.57 liters) per minute. Unless you know to the contrary, assume the incoming
potable water temperature is 50 degrees F (10 degrees centigrade). For most
washing machines you will want your water heated to 120 degrees F - 49 degrees C
and for most dishwashers (without internal heaters) 140 degrees F - 60 degrees
C. To determine how much of a temperature rise you need, subtract the incoming
water temperature from the desired output temperature.
Most tankless hot water heaters are rated for a variety of inlet water
temperatures. Select the model that most closely meets your needs. Chili Pepper
gives the following example: Assume one hot water faucet open with a flow rate
of 0.75 gallons (2.84 liters) per minute. One person in the shower using a
shower head with a flow rate of 2.5 gallons (9.46 liters) per minute. Add the
two flow rates together. If the inlet water temperature is 50 degrees F - 10
degrees C, the needed flow rate through the heater would need to be no greater
than 3.25 gallons (12.3 liters) per minute. Faster flow rates or cooler inlet
temperatures will reduce the water temperature at the most distant faucet. Some
systems are thermostatically controlled. They can vary their output temperature
according to the water flow rate and the inlet water temperature. This is useful
when using a solar water heater for preheating the inlet water. If, using this
example, you connect this same tankless water heater to the outlet of a solar
system, it only has to raise the water temperature a few degrees more, it at
all, depending on the amount of solar gain that day. Thank you Chili Pepper
Appliances.
COMPARISION OF A RINNAI SYSTEM TO GAS AND ELECTRIC 40 GALLON HOT
WATER TANKS I have referenced the Rinnai system several times. I
found an independent study done by the Okaloosa Gas District in Valparaiso,
Florida that measured a Rinnai system against both a gas and electric fired
40-gallon hot water tank. The three key factors it measured were: hot water
recovery time, energy efficiency and economic savings. The Federal Register
developed, in part, the testing procedure guidelines used by the Okaloosa Gas
District. The Federal Register provides a standard for fair comparison between
energy efficiency, energy use and the operating cost of each water heater under
the same conditions of testing. Before starting this test each unit was set to
output water at 135 degrees F. What they did was draw hot water from each
heating system every 30 minutes each weekday from 7 am to 3 pm for a total of
360 draws. The energy meter readings and cumulative water drawn were recorded at
the start of each draw. The results showed that the Rinnai provided consistent
135-degree water. The electric and gas heaters couldn't maintain that
temperature. Furthermore the operating costs of the Rinnai was considerably
lower than both of the others. With the Rinnai the average monthly cost was
$6.50 less than the gas-fired 40 gallon tank and $21 less than the electric
40-gallon tank. With regard to energy consumption, the electric 40-gallon tank
used 332.0 kilowatts per hour while the Rinnai used just 0.6 kilowatts during
the same time. Measured against the natural-gas fired tank, the Rinnai saved, on
average, 6.6 terms of natural gas. With regard to recover time the test
evaluated the time it took each unit to reheat water to a desired temperature.
The natural gas-fired unit took thirty-three minutes to full recovery while the
electric tank system took approximately one hour. The Rinnai wasn't involved in
this test since it doesn't store water. It is connected directly to the water
line and heats water only when a hot water tap is opened. This, of course,
allows Rinnai owners the luxury of using several sources of hot water at the
same time with no loss of temperature consistency.
