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Hi! from Randy at
Inquiring Eye Home Inspections!
Introduction
The following is your bi-monthly newsletter. Each newsletter is
written by me and addresses topics that are relevant in the homes we
all work with on a daily basis. March’s newsletter contains two
smaller articles, but both are on topics you may not have had any
contact with as of yet.
One article addresses an item required in any home built since 2002,
an “Arc Fault Circuit Breaker.” This circuit breaker is designed to
help prevent electrical fires caused by “electricity arcing” in
wiring in homes. In 2002 they were required for all bedroom
circuits. In 2008 that was further expanded to include all
accessible receptacles in the rooms of a house. So, no matter
whether you’re representing a listing or buying client, of a new
home, this is a subject you should become more conversant in.
The second article is on “Tankless,” or on-demand hot water heaters.
This is a component found in many European and Japanese homes but is
a relative newcomer here in the United States. This hot water
generation system provides hot water without the need for a
reservoir or “back-up” storage tank, to provide an ample supply of
hot water of a home. The article also discusses some cons of the
system as well.
Enjoy your reading and again if you have any questions please don’t
hesitate to call or email me back. Topics of interest are also
appreciated.
Arc Fault Circuit Breakers
Over 40,000 fires are caused by arcing and sparking every year
because of damaged household electrical wiring. These arc-related
fires can create sparks and temperatures that approach 10,000
degrees Fahrenheit. These fires claim over 350 lives annually and
injure many more. With recent technology, many of these fires are
now preventable. A device identified in the 1999 National Electric
Code called an Arc Fault Circuit Breaker is designed to provide this
added protection from unsafe wiring conditions. When unwanted arcing
occurs, it generates high temperatures that can ignite combustible
items such as wood, paper, cloth and carpets. This electrical arcing
can occur in damaged or inadequately insulated wires or cords.
Potential damage may occur when the older wire insulation has
deteriorated or grown thin by bending, stressing, the lines or the
build up of excess heat. Other causes include; puncturing the wire
insulation when home owners hang pictures, or electricians piercing
the cable when securing the wiring to framing, poorly installed
outlets and switches, appliance cords caught in doors or under
furniture, when household furniture is pushed against plugs in
outlets, or when electrical cords are exposed to excessive amounts
of heat from home heating systems and sunlight.
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An Arc Fault Breaker responds differently than the typical circuit
breaker in an electrical panel. A conventional breaker “faults” or
responds to overload conditions or short circuits. An AFCI is
selective in that it protects against conditions that produce
erratic current flow. An AFCI continuously monitors current flow and
is able to sense between normal and unwanted arcing conditions. When
an unnatural condition is detected, the control circuitry trips the
internal contacts, de-energizing the circuit, (shutting off the
power). Arc Fault breakers are a portion of conventional circuit
breakers – serve a dual purpose- combining traditional overload and
short circuit protection as well as arc fault protection. An Arc
Fault should not occur during normal arcing conditions, which can
occur when a switch is opened, (turned on), or when you see an arc
when a plug is pulled from a receptacle. It should be noted that
AFCI’s will detect most, but not all, arcing conditions.
As of January 1, 2002 AFCI’s were required in all outlets for
bedrooms in new residential construction. This area of the home was
first identified as the source of many electrical arc related fires.
As of the NEC Code for 2008 Arc Fault Breakers are required for all
non GFCI outlets within a residential dwelling. Arc Fault breakers
should also be strongly considered for use in older homes where the
electrical wire insulation has the potential to be compromised or
the wire insulation does not meet today’s heat resistance standards.
AFCIs vs. GFCIs
The AFCI should not be confused with the GFCI or ground fault
circuit interrupter. The GFCI is designed to protect individuals
from severe or fatal electric shock caused by contact with water
while the errant electricity is seeking a ground source (through a
person). The AFCI protects against fires caused by arcing faults.
The GFCI also can protect against some electrical fires by detecting
arcing and other faults to ground but cannot detect hazardous
across-the-line arcing faults that can cause fires. |
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Tankless Hot
Water Heaters
Here in the Northeastern United States, we use a variety of methods
to heat our potable hot water for use in showers, dishwashers and
clothes washers. The most common residential hot water heating
systems are a direct fired oil, gas, or electric storage tank-type
water heater. Other methods may be an indirect fired hot water
heater, or tankless coil hot water systems. Both of these systems
rely on a gas or oil fired boiler to provide the heat for warming
the water.
No matter which method you use for heating hot water, these systems
can account for upwards of 30 % of your total energy consumption.
These traditional storage tank methods or boiler heated hot water
systems provide a reservoir of hot water to be constantly heated for
later consumption. These systems all rely on aquastats (thermostats
designed for use in water) to maintain the hot water at a
predetermined temperature. As a result 10 to 20 % of the energy used
to heat hot water can be consumed in maintaining that constant
temperature in your storage system. This ability to have a constant
reservoir of hot water is called “standby losses.”
However, in Europe and Japan, many residences use a tankless (no
storage tank present) hot water heating system. These hot water
heating systems are called “on demand” hot water heaters. Here in
the United States, tankless water heaters are a relatively new
phenomenon and just starting to gain popularity. Because they have
been popular overseas for so much longer, the top brands of tankless
units are from Europe and Japan.
Tankless water heaters are compact heating units that provide hot
water as it is needed, and have no storage tank present. These
tankless systems come in two varieties; a whole house unit that is
designed to provide hot water for the entire house, from a central
location, or a point of use system that has less capacity and is
designed to heat enough hot water for use at one or two fixtures.
Tankless water heaters are available in natural gas, propane and
electric models. Tankless water heaters are rated by the maximum
flow rate at which a desired temperature rise is met. They are
available in a variety of capacities providing a hot water flow rate
of between 2 to 5 gallons per minute. When a hot water tap is turned
on, cold water travels through a pipe into the unit. Either a gas
burner or an electric element heats the water.
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In general, gas tankless heaters have larger capacities to deliver
hot water than their electric counterparts, and are the most common
fuel supply source. Remember, natural gas must be available in the
street to be able to utilize it as a fuel. Propane would provide a
natural gas alternative. Gas tankless water heaters, use
high-powered burners to quickly heat water as it runs through a heat
exchanger. Natural gas and propane units also need proper venting of
the combustion bi-products which will add additional cost to there
installation, or may not be viable under certain styles of
construction.
Electric tankless water heaters do not heat water as quickly as
natural gas, which usually makes them ill-suited to be used as a
central water heater as a primary source. Electric tankless water
heaters require a high electric power draw. As a result, the
electric service from the street to the house should be evaluated to
guarantee that the service is of sufficient quantity (size) to
handle all of the house’s electrical needs.
Other considerations:
Manufacturers of tankless water heaters are fond of proclaiming
their products’ ability to provide an endless amount of hot water,
but surveys of users complain of inconsistent water temperatures.
Nor do tankless water heaters deliver hot water instantaneously. It
takes time to heat the water to the target temperature, and just
like storage water heaters any cold water that has been standing in
the pipes needs to be drained, or used, from the pipes first before
hot water will be received.
Whole house “on demand” units are really only optimal for smaller
houses or households where the occupants have staggered schedules
and there is a staggered demand for hot water. Bathtubs may need to
be filled slowly if the heater cannot keep up with the hot water
demand. |
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