Plumbing Code Update Thermostatic mixing valves required on DHW System

Serving over 30,000 HVAC/Refrigeration & Plumbing Contractors Across Canada
New Certification
Contractor Survey Prize
for Hydronics
WIN
Professionals
1 of 2 Honeywell
Step Tool Boxes
Tips for Selling
Over $500 Value
Commercial Service
Agreements
Plumbing Code Update
COMPLIMENTS OF YOUR WHOLESALER:
eement No. 40034889
Thermostatic mixing valves
required on DHW System
oduct Agr
November/December 2003
Canada Post Pr
$3.50

---

c o d e u p d a t e
Proposed National Plumbing Code
amendment will impact water heater
installations in new construction
Canada’s newest plumbing code pro- Europe in its recognition of the need to bacteria that causes Legionnaire’s dis-
posal, up for review by the
protect the public from domestic-hot-
ease – multiplies in warm water.
Canadian Commission on Building
water-related injury and death. At 60º C
Destroying the bacteria requires
and Fire Codes in early 2004, will
(140º F), water can scald a child in one
scalding water temperatures of at
require contractors to change water
second, and cause third-degree burns in
least 60º C (140º F).
heater installations to safeguard the
adults in five seconds. It’s estimated that
The only solution that resolves both
public from a dual threat posed by
more than 5,000 people suffer burns
public health issues is to maintain
domestic hot water.
from scalding water every year. A hun-
stored water at a high temperature,
The proposed objectives stipulate
dred scalding victims die.
and temper it before distributing it
that residential hot water installations in
But if water heaters are simply
from the tap.
new construction must deliver water to
turned down to prevent scalding, bac-
Jean Pichette, president of HG
fixtures at a temperature no greater
teria thrives. Recent studies show
Specialties based in Laval, Quebec,
than 49º C (120º F) to protect against
that Legionella Pneumophilia – the
applauds the proposed plumbing
scalding. In addition, the proposed code
cautions against storing water at tem-
peratures below 55º C (131º F) because
of the risk of contracting deadly
Legionnaire’s disease from the domestic
hot water supply.
Addressing these public health
issues now is considered so important
that the proposal, originally intended as
part of the 2005 National Plumbing
Code, is expected to be approved in
January for implementation on an inter-
im basis by mid-2004.
A single change in water heater
installation can accomplish both
code requirements – high tem-
peratures for water storage
and low temperatures for
water distribution – according
to Heath Sharp, general man-
ager for valve manufacturer
Cash Acme, a division of The
Reliance Worldwide Corporation.
“With minimal extra time and
expense, a thermostatic mixing valve
placed at the water heater provides a
cost-effective solution to the code’s
mandates,” Sharp says. His recommen-
dation comes from first-hand knowl-
edge: Sharp experienced the nation-
wide implementation of similar code in
Australia almost a decade ago. (See,
The Australian Experience.)
Diagram of compliant installation:
Why a water heater code change?
Water heater set to 60º C (140º F) eliminates bacterial growth. Thermostatic mixing valve set to 49º C (120º F) delivers tempered
Canada is joining Australia, New
water to all fixtures. Source: Cash Acme
Zealand, the United Kingdom and
6 • NOVEMBER/DECEMBER ’03 • CONTRACTING CANADA

---

c o d e u p d a t e
codes as a positive step for the indus-
try. “With the changes to the code,
there are opportunities for contrac-
tors to grow their businesses while at
the same time improving the safety of
their installations.”
Master valve vs. Point-of-use valves
The proposed code allows contrac-
tors the flexibility of choosing either of
two methods for meeting the objective.
One solution is to install a master valve
at the hot water source, providing tem-
pered water for the whole house. A sec-
ond solution is to install end-use valves
at each point of use, allowing different
maximum water temperatures to be set
at each outlet.
“A single master valve is the simpler,
lower cost installation,” Sharp says.
“Multiple valves obviously raise cost and
require more time to install.”
Even with a master mixing valve,
Sharp recommends automatic compen-
sating valves in shower installations to
Heatguard 110-D thermostatic mixing valve and how it works
prevent a toilet flush from diverting the
shower’s cold water supply. While tem-
pered water will not scald, a bather
The Australian Experience
could experience unexpected tempera-
ture shock, leading to possible injury
Australia adopted hot water storage
who live in older homes. Even in states
from a fall.
and delivery codes on a state-by-state
with codes that do not address retrofits,
The proposed code permits hotter
basis beginning in 1994. By 2000,
contractors have a duty to inform con-
water delivery to dishwashers and
every state in the country had enacted
sumers of the risks. Plumbing contrac-
clothes washers, if desired. In that case,
plumbing codes similar to Canada’s
tors can be held liable for failure to use
a separate hot water pipe can be run
newest proposal.
their knowledge to safeguard cus-
directly from the heater to provide hot
Heath Sharp, now general manager for
tomers’ health.
water for washing. This solution does
valve manufacturer Cash Acme North
“Since some 80 percent of new
not pose a great problem for the con-
America, a division of Australia-based
water heaters are installed in existing
tractor because kitchens and laundry
Reliance, witnessed firsthand the imple-
residences, contractors now see the
rooms are typically located close to the
mentation of the new plumbing code. It
code as a real opportunity to grow their
water heater. The common two-pipe sys-
was an easier transition than anyone
businesses,” Sharp says. Each replace-
tem will suffice for the remainder of the
expected. “Initially, contractors were con-
ment job offers the prospect of selling a
home’s plumbing needs.
cerned about the extra cost of a master
water heater plus a thermostatic mixing
mixing valve, and the extra time required
valve that will deliver safely stored, tem-
Choosing a suitable valve
to install it,” Sharp says. “Within six
pered water.
The first consideration in selecting a
months, the new installation design had
valve is compliance with the Canadian
been totally accepted.”
Standard CSA B125. Contractors can
Several Australian organizations
Additional resources
install with confidence an approved
worked together to help spread the word
and their web sites:
valve bearing either the cUPC or CSA
about the new code through a series of
seal, indicating that it has passed rigor-
workshops. “Contractors are very good
National Plumbing Code of Canada:
ous standards in its manufacture.
at dealing with change,” Sharp says.
http://www.nationalcodes.ca/npc/indexe.shtml
Customer satisfaction is a contractor’s
“Once they see how pleased customers
next priority for selecting a temperature
are with the benefits of the change, they
Cash Acme: http://www.cashacme.com
control valve. The key factor in customer
find they can use their new expertise to
satisfaction and repeat business for the
upsell water heater installations in exist-
Plumbing Manufacturer’s Institute:
contractor is the valve’s reliability.
ing construction.”
http://www.pmihome.org/tempcontrol.htm
Three types of thermostatic
Some Australian states have updat-
valves are generally available: a liq-
ed their codes to address replacement
Association of Water Technologies:
uid-filled bellows type; a bi-metallic
water heaters, requiring an upgrade in
http://www.awt.org
type; and a more technologically
water storage and delivery for people
advanced encapsulated wax type.
CONTRACTING CANADA • NOVEMBER/DECEMBER ’03 • 7

---

c o d e u p d a t e
The liquid-filled bellows valve is used
primarily in larger commercial appli-
cations. Its complexity, high initial
cost and high maintenance require-
ments make it unsuitable for wide-
spread residential installation.
The bi-metallic valve was the first
mixing valve developed for smaller
installations. The valve’s working parts,
made from two different metals, are
prone to electrolysis, scaling and corro-
sion. Without frequent care, a bi-metallic
valve can lose its ability to deliver water
at a constant temperature.
The most advanced thermostatic
mixing valve makes use of encapsulated
wax technology. The valve is simple,
inexpensive and reliable, and delivers
water within a three-degree tempera-
ture range. In most cases, the valve will
continue to operate without mainte-
nance for the life of the water heater.
Thermostatic mixing valves are read-
Cutaway diagram of encapsulated wax thermostatic mixing valve:
ily available from global manufacturers
who have been supplying Australia,
Fluctuations in temperature due to changes in supply conditions cause the wax within the element to expand or contract. In turn,
the element shuttles the piston to regulate the relative amounts of hot and cold water entering the valve, thus maintaining an
Europe and other markets for several
essentially constant delivery temperature. In case of cold water failure, the valve automatically shuts off hot water delivery.
years. This means that when the new
(Source: Cash Acme)
code goes into effect, contractors will
have no difficulty finding valves to meet
the new objectives.
For example, Cash Acme manufac-
tures the Heatguard line of factory-tested,
factory-set valves. Certified to CSA B125,
the valves allow compliance with the
requirements of Canada’s proposed code,
as well as the practical considerations of
installation contractors. The valves are
TECH TIP
produced to fit 1/2", 3/4" and 1" pipe, with
a variety of fittings for different types of
Repairing Threaded
connections, including sweated, threaded,
compression, CPVC and PEX. Cash Acme
also offers a unique 4 in 1 service fitting
PVC Joints
for use with the Heatguard valves.
Pichette, whose company has distrib-
Because pipe threads are tapered, over-tightening or using too much
uted Cash Acme/Reliance valves in
Teflon tape
silicone,
service tip
may crack the fitting. If you have time to let it set, try
Canada for several years, says the com-
which will lubricate the fitting when it is being inserted and fill
pany’s Heatguard products are the lead-
in any imperfections. To avoid pushing the silicone into the plumbing and
ing line of thermostatic valves in the
clogging pumps and jets, always apply silicone to the male threads.
Canadian market. “Most contractors
To repair a cracked PVC bushing:
already are familiar with the valve and
• Clean out any old Teflon tape or silicone and thread the element or
its robust and effective function.”
fitting back into the bushing to slightly open up the crack.
Once installed, the presence of a
• Apply primer and glue and remove the fitting to allow the crack to
master thermostatic mixing valve deliv-
close up.
ers an additional, unexpected benefit,
• Attach a pipe/gear clamp around the bushing to prevent the crack
Pichette says. “When the water heater
from reopening. Reinstall the element or fitting with silicone and allow
is set to a higher temperature, con-
24 hours to cure.
sumers get a greater effective volume of
hot water,” he says. “The new home-
Note: Attaching a gear clamp before threading a fitting into a PVC
owner is rarely aware of the difference
bushing will prevent cracking.
in his plumbing. He simply knows that
his new water heater works better than
any he’s ever owned before.”
8 • NOVEMBER/DECEMBER ’03 • CONTRACTING CANADA

---