Hidden
costs:
> Hot water takes just as long to reach faucet > tankless
is
not 'instant' unless located under sink or next to bathroom
> Tankless warranty does not match 20-year claims made by
promoters
> check warranty papers, since repairs can leave you without hot
water until parts arrive
> Savings does not match promoter claims >
exception: household with reduced consumption, and
with bath/kitchen located near tankless unit will realize more savings
than home with multiple tankless units blazing each time a bath is
run.
> Promise of unlimited hot water is not consistent with claims
of energy savings. Tankless consume more energy to heat a gallon of
water than storage-type heater. Proof: Notice that tankless-gas require
larger gas line and larger exhaust. And tankless-electric require
90-120 Amps.
>
Tankless are prone to
lime build-up
in heat exchanger. Softener and filter required, adding long term
expense.
> Hard water reduces tankless efficiency within 2 years.
De-liming each 9 months can help, but pressure
regulators clog causing failure to heat. Constant maintenance
eliminates savings.
>With correct water softener, Tankless maintain 79% efficiency.
In
comparison, electric storage heaters operate at 99% efficiency with
hard water or soft water, and can be maintained by homeowner without
expense
of softener or technician. Read
pdf
>
Tankless units are not made in your town. They are high tech gadgets
requiring precision engineering. Heat exchanger is special metal
alloy and expensive to replace, especially if improper
installation
causes dripping condensation that corrodes exchanger.
> No hot water during power loss > no power to
electronics, no hot water. Both gas and electric
tankless units require 120V for electronics inside unit. By comparison,
storage tanks hold heated water for hours.
> Minimum 1/2 to 3/4 gallon water flow before tankless turns on.
Tankless start heating when
water begins to move through pipe. Faucet located far away might not
activate heater immediately. Consumer might wait longer for hot water
to arrive. Hot water may not arrive. Ask questions.
> Water flow requirements for tankless are not consistent with
water conservation
>
Low water
pressure causes tankless computer to shut down burner. Homes
with
water wells & homes in MUD & PUD districts with low
water pressure are not suitable for
tankless. Check your pressure for a full day. Check the tankless spec
sheet.
Additional
in-line
pressure tank required. Turning up well pressure shortens life of well
parts and uses more water.
> Hot water circulation pumps will not activate tankless.
Tankless require 1/2-3/4
gallon per minute water flow. Read spec sheet on tankless and on
circulation
pump. Larger circulation pump likely needed > not consistent
with energy savings.
>
Tankless problems are difficult to diagnose. No hot water during delay.
Tankless are complex and
problems vary from brand to brand. Keep manufacturer
website and trouble
page in your records.
>
Homeowner dependent on professional service. Repairs are not done
by low-cost handyman.
>
Parts are not interchangeable between tankless brands. Parts not
available at
home center. Parts may not be available on weekend. If tankless unit
lasts 20 years as claimed, who will carry parts in year 15? Ask
questions.
>
Homeowner cannot install tankless. Each brand has
installation protocol
that must be followed for warranty to take effect. Warranty is void
unless installed by person
trained by manufacturer. Homeowner installed tankless needs repair.
>
Before buying tankless, add up total BTU of existing gas appliances and
heating, and then add BTUs for tankless. Check that gas meter is large
enough to supply needed gas. Undersized gas line or gas meter will
cause tankless and other gas appliances to malfunction.
> Oversized units are usually installed
to meet home demand. Oversizing eliminates all savings. Ask questions.
> Incoming cold water during winter might not heat without
oversized unit or additional staging tank. See staging tank
> Gas: Converting to tankless-gas is 3x more
expensive. Larger gas
line is required. Larger vent. Need for more combustion air. Read
installation spec
sheet & ask questions.
>
Electric: Converting to tankless-electric requires additional 90-120
Amps. Check your main breaker to see total amps of your service. New
breaker panel and service may be necessary. Read tankless spec sheet
& ask questions.
>
Tankless use more energy per minute than storage-type heaters. The
promise of unlimited hot water is not consistent with promise of energy
savings.
> Tankless units have internal heater to keep unit from freezing
in
winter, which adds standby cost similar to storage-type heaters. Check
spec sheet.
>
All gas burning appliances send heat up vent stack. This is wasted
energy. A heat exchanger can recapture some vented heat. However
if tankless vent is slowed by heat exchanger, combustion will
slow, causing computer to turn off unit. In comparison, new
high-efficiency gas
storage heaters recapture large percentage of vented heat. Compare
innovations and ask questions. Read about water heating innovations.
> All gas burning appliances draw air from outside. Tankless
burn more fuel per minute and require more air. Unit located
in house might require
incoming vent pipe, or drafty location like garage. Drafty locations
have colder incoming water in winter. Tankless may not heat water in
winter. See staging tank
>
Tankless cannot store heat gathered from other sources.
In comparison,
storage-type
heaters can store heat gathered from heat-pump-exchanger,
solar-heating, geothermal, drain water recovery & wood stove.
>
Future planning: Ordinary storage-type heaters can be adapted many ways
to meet future
needs: For
example: low flow water systems that conserve water, integration with
solar heaters,
integration with heat-exchangers. Tankless can only use hydrocarbon
fuel with high water
flow.
>
Recapturing CO2 from gas appliances at each home is not very
likely > converting to innovative electric water
heat is likely
the
future, since CO2 from electric generation can be centrally recaptured
at power plant
> Your storage tank works fine. It is easy to
fix and replace. It is cheaper over the long term. There are many ways
to reduce energy costs and save with storage-type heaters including
insulation, off-peak thermostats, and timers. Read
Sources:
see links at bottom of page
|
