Water Chemistry Requirements - Westinghouse WGR-076 Series Installation, Start-Up, Maintenance, Parts, Warranty

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candle or smoke from a cigarette.
6. After it has been determined that each appliance remaining
connected to the common venting system properly vents
when tested as outlined, return doors, windows, exhaust fans,
fireplace dampers, and any other gas burning appliances to their
previous condition of use.
7. Any improper operation of the common venting system
should be corrected to conform to the National Fuel Gas Code,
ANSI Z223.1. When resizing any portion of the common venting
system, the system should approach the minimum size as
determined using the appropriate tables in Appendix G of ANSI
Z223.1.
Figure 2 - CO Warning Label
H. Water Chemistry Requirements
Chemical imbalance of the water supply may affect efficiency
and cause severe damage to the water heater and associated
equipment. Westinghouse recommends having water quality
professionally analyzed to determine whether it is necessary to
install a water softener. It is important that the water chemistry
on both the domestic hot water and central heating sides are
checked before installing the water heater, as water quality
will affect the reliability of the system. In addition, operating
temperatures above 135 F will further accelerate the build-up of
o
lime scale and may shorten the service life of the water heater.
Failure of a water heater due to lime scale build-up, low pH, or
other chemical imbalance IS NOT covered by the warranty.
Outlined below are water quality parameters that need to be
met in order for the system to operate efficiently for many years.
Water Hardness
Water hardness is mainly due to the presence of calcium and
magnesium salts dissolved in water. The concentration of
these salts is expressed in mg/L, ppm, or grains per gallon
as a measure of relative water hardness. Grains per gallon is
the common reference used in the US water heater industry.
Hardness expressed as mg/L or ppm may be divided by 17.1 to
convert to grains per gallon. Water may be classified as very soft,
WHL-001 Rev. 3.16.15
slightly hard, moderately hard, or hard based on its hardness
number. The minerals in the water precipitate out as the water
is heated and cause accelerated lime scale accumulation on
a heat transfer surface. This lime scale build-up may result in
premature failure of the water heater. Operating temperatures
above 135 F will further accelerate the build-up of lime scale
o
and may shorten the service life of the water heater.
Water that is classified as hard and very hard must be softened
to avoid water heater failure.
CLASSIFICATION MG/L OR PPM
Soft
Slightly Hard
Moderately Hard
Hard
Very Hard 180 and over
If the hardness of the water exceeds the maximum level of 7
grains per gallon, the water should be softened to a hardness
level no lower than 5 grains per gallon. Water softened as low
as 0 to 1 grain per gallon may be under-saturated with respect
to calcium carbonate, resulting in water that is aggressive and
corrosive.
pH of Water
pH is a measure of relative acidity, neutrality, or alkalinity.
Dissolved minerals and gases affect water pH. The pH scale
ranges from 0 to 14. Water with a pH of 7 is considered neutral.
Water with pH lower than 7 is considered acidic. Water with a
pH higher than 7 is considered alkaline. A neutral pH (around
7) is desirable for most potable water applications. Corrosion
damage and tank failures resulting from water pH levels
of lower than 6 or higher than 8 ARE NOT covered by
warranty. The ideal pH range for water used in a water heater
is 7.2 to 7.8.
Total Dissolved Solids
Total Dissolved Solids (TDS) is a measurement of all minerals
and solids dissolved in a water sample. The concentration of
TDS is usually expressed in parts per million (ppm).
Water with a high TDS concentration will greatly accelerate
lime and scale formation in the hot water system. Most high
TDS concentrations precipitate out of the water when heated.
This can generate a scale accumulation that will greatly reduce
the service life of the water heater.
The manufacturer of the water heater has no control over
water quality, especially TDS levels in your system. TDS in
excess of 2000 ppm will accelerate lime and scale formation
on the element or the heat exchanger. Water heater failure
due to TDS in excess of 2000 ppm IS NOT covered by warranty.
Failure of a water heater due to lime scale build-up IS NOT
covered by warranty.
Hardness: 7 grains
Chloride levels: 100 ppm
pH levels: 6 - 8
TDS: 2000 ppm
Sodium: 20 mG/L
GRAINS/GAL
0 - 17.1 0 - 1
17.1 - 60 1 - 3.5
60 - 120 3.5 - 7
120 - 180 7 - 10.5
10.5 and over