Propane Unlimited Tankless Water
Heater Operation - No Moving Parts
So, your hot water tank has sprung a
leak and you want to know why I switched to a Tankless Propane Water
Heater and am I happy with it.
I guess I
first started thinking about Propane Tankless Water Heaters during my
travels. I noticed in the U.K., Europe, Pacific Rim countries and many
other parts of the world, that everyone uses Propane Tankless Unlimited
Water Heaters. Common sense told me there had to be a reason.
Fuel costs have
historically been higher in the rest of the world, resulting in more
efficient water heating equipment. I learned that Propane Tankless
Unlimited Water Heaters are 25-30% more efficient than tank types
which have to burn 25-30% longer just to keep the water in the tank hot.
Also, because they have single or multiple flues running up the middle
of the tank, when the burner is off cool air can travel through and draw
significant heat back out of the stored water which is very wasteful and
inefficient. My Propane Tankless Unlimited Water Heaters has no
tank to keep hot or to lose heat through, and the burner only comes on
when hot water is needed. This is how I save 30% and contribute 30% less
flue gas emissions to the environment.
I next found out that
even though a Propane Tankless Unlimited Water Heaters costs more than
the tank type water heater, they last 3 to 4 times longer. In North
America we are used to throwing away the whole water heater every 5 to 7
years when it leaks. Propane Tankless Unlimited Water Heaters are
designed to be repaired - you never throw them out. This, to my mind, is
investment and conservation smart.
I guess the clincher was
the time we were traveling with the Murrays and one night we all had to
share a small cottage - five adults and four kids. We had driven all
day, we were hot and dusty and decided we could clean up and go out for
supper. We had nine leisurely showers one after the other and never ran
out of hot water - and yes, you guessed it, there was a Bosch Propane
Tankless Unlimited Water Heaters mounted right on the wall of the
kitchen unit. We just couldn't believe it!
I bought my Bosch Propane
Tankless Unlimited Water Heaters when my tank heater failed, and its
small size (31"H x 18"W x 9"D) and the fact that it uses no floor space
was really helpful when we remodeled our kitchen. My friend Ron, who's a
plumber, said it was just as easy to install as a tank type.
If you asked me if there
were any negative factors, I would really have to say no, but there are
two things you should be aware of. First, because the heaters are flow
activated and operate on a pressure differential, it's very important to
have a minimum of 30 psi water supply pressure. The other point is that
while you can run a shower continuously and never run out of hot water,
you can't run more than one shower or major appliance at the same time.
However, this doesn't worry us as most homes, even with 2 or 3
bathrooms, rarely run baths or showers at the same time because of
temperature fluctuations and the fact that with heavy demand, a tank
type heater soon runs out of hot water and you have to wait for it to
heat up again. Propane Tankless Unlimited Water Heaters never keep you
Are we happy with our
Bosch Propane Tankless Unlimited Water Heaters ? We save up to 30% on
our gas bill, conserve energy, save space, protect the environment,
never run out of hot water and we have a smart, long term investment
that is going to save us money for as long as we burn gas - you bet we
Low Volume Tankless Water Heater with Pilot Ignition. Ideal For Low Flow
Camp or Cottage Use. This Handy Small And Compact Unlimited Water Heater
is Also Popular In RV and Marine, Hot Tubs, Portable Bush Showers, Animal
Grooming, Mobile Blind Cleaning Trucks, Mobile Food Service Trucks Etc.
Mounts on wall for easy installation
Compact and lightweight
Modulating gas valve to control
Pressure relief valve included
- Standing pilot ignition
- 78% average efficiency
30,735 - 74,900 Btu
30,735 - 74,900 Btu
Min. Flow To Activate
||0.5 Gal Per
Minute to Activate
||45°F rise @
@ 2.1 gpm
65°F rise @ 1.7 gpm
77°F rise @ 1.5 gpm
rise @ 1.3 gpm
||28.8" h x
12.2" w x 8.5" d
Modulating Gas Valve
Internet Special: $1099
Tankless water heaters and Tankless Propane gas Water Heaters provide
- Long term energy savings: Though a tankless gas water
heater typically costs more initially, it usually costs less to
operate because of lower energy use—since it only heats water when
required instead of continuously maintaining a tank of heated water.
Even homes or buildings with high demand for hot water may realize
some level of savings. If instant hot water at taps at limited hours
is a priority, a recirculation system can be accommodated by using
an aquastat and timer to decrease the added heat loss from the
recirculation system. If the storage tank of an Propane Gas
heater is highly insulated, so that the outer surface of the tank is
only slightly warmer than the ambient air, the savings with a
tankless heater is less.
- Unlimited hot water: Though flow rate determines the
amount of hot water the Tankless gas Water Heater can produce, it
can deliver it at that flow rate indefinitely. However, this can
also be an ecological disadvantage, as running out of hot water
limits use, but a tankless gas water heater provides no such limit.
- Less physical space: Most tankless gas water heaters can
be mounted on a wall or internally in a building's structure. This
means less physical space must be dedicated to heating water. Even
systems that can't be mounted on walls take up less space than a
tank-type water heater.
- Reduced risk of water damage: No stored water means there
is no risk of water damage from a tank failure or rupture, though
pipe or fitting failure remains possible.
- Temperature compensation A temperature compensating valve
tends to eliminate the issue where the temperature and pressure from
tankless gas water heaters decrease during continuous use. Most new
generation tankless gas water heaters stabilize water pressure and
temperature by a bypass valve and a mixing valve incorporated in the
unit. Modern tankless are not inversely proportional, because they
regulate the amount of water they heat and discharge, and therefore
stabilize water temperature by using a flow control valve.
Temperature change, not flow speed, is the issue the water heater
must address. The wider the temperature rise, the less flow from the
unit—the smaller the temperature rise, the greater the flow. The
flow control valve, in conjunction with thermistors, maintains a
stable temperature throughout the use of the tankless gas water
- Safety Tankless gas Water Heaters precisely control water
temperature, which means dangerous temperature levels and spikes are
Tankless water heaters—also called instantaneous,
continuous flow, inline, flash, on-demand, or
instant-on water heaters—are gaining in popularity. These
water heaters instantly heat water as it flows through the device,
and do not retain any water internally except for what is in the heat
Copper heat exchanger are preferred in these units because of their
high thermal conductivity and ease of fabrication.
Tankless heaters may be installed throughout a household at more than
one point-of-use (POU), far from a central water heater, or larger
centralized models may still be used to provide all the hot water
requirements for an entire house. The main advantages of tankless water
heaters are a plentiful continuous flow of hot water (as compared to a
limited flow of continuously heated hot water from conventional tank
water heaters), and potential energy savings under some conditions. The
main disadvantage of these systems are their high initial costs
(equipment and installation).
The tankless gas water heater is normally turned off, but is equipped
with flow sensors which activate it when water travels through them. A
negative feedback loop is used to bring water to the target temperature.
The water circulates through a copper heat exchanger and is warmed by
gas. Since there is no finite tank of hot water that can be depleted,
the heater provides a continuous supply. To protect the units in acidic
environments, durable coatings or other surface treatments are
available. Acid-resistant coatings are capable of withstanding
temperatures of 1000°C.
Common in Europe and Japan for 75 years, tankless water heaters are
still fighting for market share in Canada. The rising cost of energy may
give them the boost they need to replace conventional storage tanks.
Recently my gas water heater sprung a leak. It had been working away
faithfully in the basement since before we bought the house 17 years
ago. Since it’s a rental from the local gas utility, I called them and
they installed a new unit. It didn’t occur to me to ask about installing
a tankless water heater, and they didn’t suggest one.
Many communities and utility companies are now promoting tankless
water heaters as a more energy efficient option than the conventional
storage units used in most North American homes. Also known as demand or
instantaneous water heaters, tankless units heat water only as it is
required, eliminating the need to have 200 or more litres of water
sitting in a heated tank, waiting to be used.
Information from Green Venture, a non-profit environmental group, and
The City of Hamilton, Ontario says that most families use hot water for
a cumulative total of about one hour per day. “The other 23 hours you
purchase electricity or gas to heat water is unnecessary,” says Green
Having a constantly heated tank of water is like leaving your car
running all night for the morning drive to work, suggests retailer
Tankless Low Energy Systems of Whitby, Ontario. On its website
(www.tanklesswaterheaters.ca), the company says that “most gas tank type
water heaters lose 6 F degrees per hour because they have a flue sucking
the BTUs out of the stored hot water.”
Green Venture says that heating water accounts for about 20 per cent
of a household’s total energy use, and that tankless water heaters can
save anywhere from five per cent to 70 per cent of the energy required
to heat water. That equates to annual household energy savings of about
30 per cent, says Green Venture.
Tankless water heaters have several other advantages as well. They
take up much less space than conventional tanks and can be hung on a
wall. Problems with mineral or scale build-up are unlikely, because
there is no water storage and they can be used with water softening
systems. They are a proven technology, having been in use in Europe and
Asia for more than 75 years. Finally, manufacturers say they last longer
than storage water heaters.
So why do most of us stick with conventional hot water heaters?
Money. Tankless water heaters can cost up to three times as much as
Until recently, there was also a question of
whether tankless water heaters could handle the capacity required for
whole-house installations. Many of the tankless heaters currently in use
are small, supplemental units installed at the point of use, such as a
remote bathroom or the laundry room.
Natural Resources Canada (NRCan) says that “depending on overall
water usage, they may not have the capacity to supply an entire home
with hot water. For this reason, they are often used as booster heaters
to supplement another water heating system.”
However, in recent years, manufacturers have been making larger
tankless units for whole-house applications. “A relatively new tankless
technology – the low mass water heater – is capable of supplying much
more hot water to the home,” says NRCan. “These systems are typically
gas-fired with electronic ignition and power exhaust, which means they
are also more efficient than conventional tankless heaters. They can be
connected to an external storage tank, if necessary.”
To find out what size of water heater is right for your house, you’ll
need to figure out how much water flow you need to meet your home’s peak
hot water demands. A report from the U.S. Department of Energy says to
list the number of hot water devices you expect to have open at any one
time, and add up their flow rates.
Next, select a manufacturer that makes a unit that can handle that
“Most demand water heaters are rated for a variety of
inlet water temperatures,” says the Department of Energy. “Choose the
model of water heater that is closest to your needs.”
A report by Platts Research & Consulting (available on the B.C. Hydro
website, www.bchydro.com) says that electric heating element and gas
requirements for tankless water heaters are higher than for storage
water heaters. A gas tankless heater uses more BTUs per hour, so it may
require larger gas lines and vents. An electric unit may require 8- or
10-AWG copper wiring, says the Platts report.
One drawback to buying a tankless water heater could be that because
they are not yet common in Canada, it may not be easy to find someone to
install and maintain your unit.
However, tankless water heater manufacturers are convinced that
storage units are on the way out, and that before long, we’ll all be
saying, “No tanks”.