About 53% of U.S.
households use natural gas water heaters, while 38% use electric and
less than 4% use oil.
Gas heaters produce more BTU's per hour and can
heat water faster than electric heaters.
Standard
2-element electric
heaters are simple to install and can be maintained to last forever.
They have higher efficiency than gas, but cost more to operate.
|
| Less than 55 gallon |
What
they said in 2014:
Under
55 gallon:
Gas heaters: No standing pilot light and flue
baffles means requires 120 volt outlet.
Gas and electric heaters might be 8" taller and 6" wider due to
insulation.
Reality
2020:
Gas water heaters still have pilot lights. Exceptions would include
power vented heaters, and condensing heaters that use hot surface
ignition ... this is unchanged
since 2014.
It's true that flue damper heaters need outlet, as do power vented, and
condensing heaters, same as 2014. But the residential and
commercial atmospheric heaters with pilot light remain on the market
and still do not need electric outlet. Review flue damper
The 50 gallon electric hybrid (heat
pump) models are taller than ordinary electric heater, but they're same
size as 2014.
Most ordinary 30-40-50 gallon heaters are probably 2" wider
and maybe 1" taller ... almost as predicted.
What
they said in 2014
The
new standard will result in approximately 43% energy savings.
Lower
energy bills would cover typical incremental costs for more efficient
water heaters (about $800) in seven years.'
Reality
2020:
The
prediction was false .... No heater
has achieved 43% efficiency gain ... and increased costs of buying
heaters has far exceeded any energy saving.
Condensing heaters have 80%
efficiency, same as 2014, and maybe more homes have been forced into
buying them.
Atmospheric and flue damper
and power vented models that were 59-63% efficient before might be
2%
more efficient after 2015 assuming manufacturers are actually making
improvements, which
is difficult to discover or prove based on resources they post ... and
since manufacturers do their own testing without oversight, the whole
situation is more than
laughable.
What
they said in 2014
Many homes will need to be remodeled to accommodate larger heater.
Reality
2020:
This might carry some truth, and would affect folks with small
living space. In this instance, a smaller heater might be necessary to
save expensive remodel,
and this would result in slight energy savings ... except offset by the
fact ...
that
an undersized heater will work harder, requiring more maintenance and
reducing lifespan of heater ... requiring early replacement of heater
... raising overall cost which far exceeds any energy saving.
|
| More than 55 gallon |
 New
energy standard April 2015
What
they said in 2014 about gas
heaters Over 55 gallon, must buy condensing
heaters with higher technology, but cost of heater and maintenance will
exceed expected savings.
Reality
2020
Yes, you must buy condensing for over 55 gallon, and costs exceed
saving, but condensing heaters deliver a lot of hot water for high
consumption homes, making it difficult to compare.
Condensing
heaters cost more to buy (running into the thousands of dollars), they
are higher technology, require more maintenance,
require power vent or power direct vent installation, require 120 volt
outlet, Condensing heaters are
generally not DIY repair.
But wait,
instead of a condensing heater, you can there are ordinary atmospheric
vented, non-condensing 74-98 gallon gas heaters that are rated
commercial grade for residential (a new category invented in 2015 to
side-step energy standard). Example 74-98 gallon spec sheet
Or instead of installing a condensing, you can install 2 heaters, but
again, it raises consumer cost and requires a
larger flue pipe.
Undersized heater will work more, costing more maintenance and
shortening life of heater.
Resource:
Review Polaris condensing heater (gas)
What
they said in 2014 about electric
heater The 30-40-50 gallon
ordinary tank will have more insulation, larger size, higher
efficiency, higher cost, but otherwise remain mostly unchanged after
2015 energy standard.
Reality
... true ... ordinary electric heaters are slightly wider and taller.
What
they said in 2014 about electric
heaters
Electric water heaters over 55
gallon must be heat
pump to meet energy standards.
Reality
2020: Hybrid
(heat pump) heaters are required unless you install 2
heaters.
Manufacturers
are sticking to their guns on this one, despite the customer needing a
rebates (you
loaning yourself money to buy something that makes no sense
otherwise).
Why is there reluctance to buy hybrid heat pumps? Hybrid heaters are
expensive. They require yearly maintenance and are generally
not DIY repair. They are noisy, tall and heavy (900 lb massive like 4
linebackers) ... they require incoming air supply (7' x 10' room),
floor
drain for condensate, yearly maintenance (cleaning air filter and
condensate drain), and can be a drain of money if unit needs $400-800
repair or consumes energy from the HVAC to heat water.
However, if
all works well, then the hot water is heated using 690 watts of power
instead of
4500 watt elements, albeit the unit reheats tank slowly unless
secondary elements kick in to assist.
Demand
Response
There are still
'ordinary' 2-element 80-100 gallon electric water heaters, but by law,
they
must be enrolled in a 'demand response program' where the lower element
of heater is
controlled by electric utility. Read spec sheet You
might be able to rewire these units to sidestep requirements, but I
have not tried or heard of anyone doing so.
Resources:
Review Hybrid electric water heaters
(electric)
Vaughn demand response control |
 Short nipple
 Combo
anode rod |
Result
of more insulation on top of 30-40-50 gallon gas and electric heaters:
Hot-cold connections
are same length as 2014 heaters, so the nipples are too short to apply
a wrench
... and nipples are near impossible to remove.
Resource:
How to remove short water heater nipple
This is huge disadvantage for customers, especially folks that have
heaters with the combo anode rod.
Anode
rods protect steel tank from rusting. Most anodes are hex head and
removed with a 1-1/16" socket, and have no connection to the nipple. See image
However
the combo anode is connected to, and part of the hot water nipple ...
the combo anode rod cannot be removed for inspection or
replacement. See image
There
is no magic answer for this problem.
This is going on ... no matter how much it costs or inconveniences you.
Resource:
How to inspect and replace anode rod
|
See example chart |
Old sizing chart
Post 2015 heaters require high tech for sizes over 50 gallon.
High tech heaters have electronic controls that are susceptible to
surge.
Plug
heater into Surge Outlet. Multiple surge protection on one circuit is
good. Do not use GFCI with water heaters, or risk errors and lockouts
etc.
Buy:
Surge
outlet
Take showers instead of bath. Showers consume 7-10 gallon hot, while
bath consumes 15-20 gallon hot. Save 10 gallons hot water each time.
To achieve same hot water consumption as previous heater without buying
more expensive heater install 2 water heaters, cut consumption,
maintain heater, turn up thermostat temperature, install mixing valve.
Buy:
Mixing
valve
Resources:
Two water heaters
9 ways to save with water heater
Maintain water heater
How to adjust thermostat
Ways to increase hot water
Calculate first hour delivery
Advantages-disadvantages mixing valve |
 |
Over
55 gallon size heaters
Picture not to scale
1) Gas heaters over 55 gallon require a condensing heater.
Approximate efficiency 80% compared with ordinary 50 gallon tank heater
60%.
50 gallon condensing 22" x 71" and 75 gallon 27" x 64" Spec sheet
Condensing
heaters produce massive amounts of hot water, but are expensive to buy,
require large gas line, power venting, yearly maintenance, plus repairs
and parts are expensive.
Note you can still
buy 'commercial grade for residential' 74-98 gallon heaters. Spec sheet
2) Electric heaters over 55 gallon require hybrid/ heat pump.
50 gallon 22" x 63" and 80 gallon 27" x 69". Spec sheet
Heat
pumps are reliable and deliver 50-80 gallons hot water but are slow to
reheat tank. They are expensive and require yearly DIY maintenance.
Payback is possible in some instances, but hybrids heat water by
leeching energy from the HVAC, making payback uncertain.
There
are still 1-element 80 gallon electric heaters that are typically used
for solar hot water collection, but for the ordinary 2-element 80
gallon electric heater, it must be enrolled in a 'demand response
program' where local power company can turn off lower element. Spec sheet
High technology water heaters increase
purchase price considerably but improve efficiency.
Both gas and electric models require more maintenance.
 Repairs
and parts are expensive.
Both
types generate condensation and require floor drain
Resources:
Review Polaris condensing heater (gas)
Review Hybrid electric water heaters
(electric) |
Energy
factor is not efficiency
Energy factor is a formula for calculating efficiency
Source for efficiency/ pdf
Chart
shows typical tank-type gas water heaters manufactured after April 2015
gained 2% efficiency over
prior years. This might
save $12-15 per year operation cost.
All
costs are energy, and new heaters
have one-time up-front cost: they use
more materials, arrive in larger boxes, take up more space and cost
more to buy. On the back end, they cost more to replace. What is the
real energy savings if a heater saves $12-15 per year, lasts 12 years
for
a total saving of $144, but
consumes more raw materials to manufacture and costs
$200 more to buy just to claim higher efficiency? |
Why
the new energy standard is suspect:
1) Aside
from reliability of self-tested products, the older
2012 energy standard is based on 135° thermostat setting. The new 2015
energy standard uses lower setting of 125° to achieve the higher
efficiency.
A lower thermostat setting is always more efficient, but means you have
less hot water in
the tank. It reduces first
hour delivery (the amount of usable hot water from a single continuous
draw), so the water heater
might run longer to keep up with
demand. This factor might eliminate the expected
savings shown on this page. Resources: Calculate first hour Ways to increase amount of hot
2) All
costs are energy, and new heaters have one-time up-front cost: they use
more materials, arrive in larger boxes, take up more space and cost
more to buy. On the back end, they cost more to replace. All costs are
energy. What is the
real energy savings if a heater saves $12 per year, lasts 12 years for
a total saving of $144, but
consumes more raw materials to manufacture and costs
$200 more to buy just to claim higher efficiency?
3) The
new water heater standards illustrate an attempt to preserve the heyday
of
consumption by using 'more efficient'
products.
Instead
of high cost efforts, why not sell a cheap
do-it-yourself insulation kit,
since most of the design difference between pre-and-post 2015 30-40-50
gallon water heaters is thicker insulation? Besides, it would not cause
the 'short water heater nipple' problem mentioned before on this page.
4) My
observation: People relying on 'the marketplace' to
solve problems
has
often resulted in promoting boutique-priced rooftop solar panel
installations, and awarding 'energy stars' to 4-person, 5000
square foot home because the massive windows are triple-pane, while
overlooking inherent efficiency of DIY solar panels installed
on a 6 person mobile home. Perhaps
more do-it-yourself decisions, and
less reliance on 'somebody inventing a new product' might be correct
solution.
Protect your investment:
How to maintain water heater
The future of water heating might be solar panels: Convert AC water heater to DC
Should you buy solar water heater |
Heaters
that plug into outlet
must have correct polarity or gas water heater will not work
Time
for 2 water heaters?
New
standards will spark innovation
