Bosch AquaStar Tankless Water Heaters FAQ'S General and Specific information on Bosch AquaStar tankless water heaters. If you do not find
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You can save between $100.00 and $400.00 dollars a year (up to 50%), depending on
whether you are comparing your savings to a natural gas, propane or
electric storage tank. Bosch Aquastar tankless water heaters without pilots will save
approximately $40 per year more. Savings also depend on usage, so keep
in mind that with the benefit of endless hot water, your showers might get
The Bosch AquaStar is manufactured with materials that will last a lifetime:
copper, brass and stainless steel. The engineering and manufacturing of a
tankless gas water heater is much more sophisticated than that for making
storage tank water heaters. For example, the Bosch AquaStar gas control
modulates the burner energy output according to the hot water flow
demand. Keep in mind, too, that you should not be buying another water
heater for 20 years or more, and that you will not need to buy extra
strapping, mounting, drip pans or leak detectors.
The AquaStar model 1600 / 125 series can replace the conventional storage tank in a
home. There is a smaller AquaStar model available for camps and cabins (1000P / 38B), and the
Bosch 2400E, Bosch 2400ES, Bosch 2400EO, and Bosch 2700ES - larger on demand model available for simultaneous demands, like two showers at
once. Check each heater page for what each tankless water heater can do
for you. Make sure you choose the right heater for your application. If you have
any questions - please hit the "contact us" button at the top of most pages and
ask our experts. We are here to help you find the perfect hot water heater for your
A simple installation should take less than three hours. Tankless water
heaters require 1/2 inch or 3/4 inch gas lines (depending on size), so if a
larger gas supply line is required, the time (hence, cost) will be more.
Venting work can also cause the installation cost to increase. The
Bosch AquaStar 1600 / 125 series requires a minimun 5 inch vent, so masonry work may be required.
The units can also be power vented through 4-inch vents, making retrofits
into existing exhaust systems less costly. Check out the power vent
accessory on the AquaStar 125 lineup page.
A licensed plumber or a licensed gas technician would be able to install
an AquaStar Tankless Water Heater. The connections at the heater are standard 1/2 inch
AquaStar 1600 / 125 Series and 3/4 inch for Bosch 2400ES, 2700ESfor water and gas lines.
On Demand Tankless water heaters are rated by gallons per minute (gpm) at specific
degree rises. Check the specifications for any given model. For example,
the AquaStar 1600P will produce 3.5 gallons per minute (gpm) at a 50
degree rise. This means you would have 105°F water at 3.5 gpm
(50-degree rise to inlet water temperature of 55°F. This is plenty for a
good shower and simultaneous hand washing at a sink. The flow rate is the
same as 210 gallons per hour at a shower temperature.
Bosch AquaStars have a modulating gas valve, so accordingly the burner flames
will increase and decrease in order to keep the temperature steady.
AquaStar tankless water heaters modulate by flow, so that the gas burners
activate according to the volume of water flowing through the heater.
Therefore, the temperatures will not vary when flow is increased or
decreased at the faucet.
Yes. When the Bosch AquaStar tankless water heater is set to activate at 0.5 gpm for the
125 / 1600 Series hot water Heaters, and the
maximum flow rate is 4.0 gpm (depending on model). At this setting, the temperature rise will be
90°F (giving 140°F water). Adding cold water produces higher flow
rates. The AquaStar can easily be set to activate at a higher flow rate, and
then it will produce up to 3.5 gpm at shower temperatures. The Bosch 2400ES and 2700ES will
produce up to 5.9 gpm. The limits are set so that the flow rates are never
too much for the burners to heat instantaneously, guaranteeing desired
temperatures at the faucets.
The temperature will remain constant but the flow will decrease. The
decrease in flow will be equal if the outlets are the same distance from the
AquaStar and if the outlets have the same flow rate. If one outlet is further
than the other from the AquaStar, the decrease will be most noticeable at
the further outlet. If one outlet has a greater flow (bathtub compared to a
sink, for example), the flow at the bathtub will not experience as much
decrease as the faucet since water runs the path of least resistance and the
tub's spigot is larger than the sink's.
The hot water at any faucet or outlet will never run out as long as you are
calling for hot water. The Bosch AquaStar tankless water heater will allow one major flow of hot
water at a time. You could run shower after shower, then when finished,
run loads of laundry, and then do the dishes, and so on. It is generally fine
to run hot water at a sink while someone is taking a shower.
The average ground water temperature is 50-55° F (ground water
temperatures vary as little as two to three degrees from summer to winter).
Because tankless water heaters operate by increasing the incoming water
temperature by a fixed number of degrees (called degree rise), knowledge
of the ground water temperature allows you to know what water
temperature a tankless water heater will produce.
There are very powerful burners located beneath the copper heat
exchanger that heat the water as it flows through the numerous feet of
copper coils. Copper transfers heat instantly to the water in the coils.
For the Bosch 125 / 1600 Series - the water valve's inside components should be replaced every
five years(average cost: $20.00). In
hard water areas, the heat exchanger should be flushed every 2-5 years.
Burners should be kept free from dust, lint and cobwebs. The exhaust
system should be inspected annually.
This is the way the Europeans and Asians have heated water for over
seventy-five years, and the engineering technology has evolved over this
time. However, since fuel costs in the U.S. have been quite low, we've
never had to think much about the waste of keeping a tank of water hot 24
hours a day.
Yes! We offer several electric tankless water heaters that can supply hot
water for one sink (point-of-use) of for an entire home (one major flow at
a time). The units can be installed in such a way as to eliminate a long
water run (plumbed independently of the main hot water heating system).
Ask for Powerstream (point of use models) or PowerStar (for the whole
house) and Ariston point-of-use mini tank.