Water Chemistry - Westinghouse WGR050NG076 Installation Instructions Manual

13
determine if there is blockage, leakage, corrosion or other deficiencies that could cause an unsafe condition.
3. If practical, close all building doors, windows and doors between the space in which the water heater remains connected to the
common venting system and other spaces in the building. Turn on clothes dryers and any appliances not connected to the common
venting system. Turn on any exhaust fans, such as range hoods and bathroom exhausts, at maximum speed. Do not operate a summer
exhaust fan. Close all fireplace dampers.
4. Place in operation the appliance being inspected. Follow the lighting instructions. Adjust the thermostat so the appliance will operate
continuously.
5. Test for spillage at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of a match or candle or
smoke from a cigarette.
6. After it has been determined that each appliance remaining connected to common venting system properly vents when tested as
outlined, return doors, windows, exhaust fans, fireplace dampers and any other gas burning appliance 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 in the National Fuel Gas Code, ANSI Z 223.1.
H. WATER CHEMISTRY
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. Failure of a heat exchanger due to lime scale build-up on the
heating surface, low pH, or other chemical imbalance IS NOT covered by the warranty.
o
Operating temperatures above 135 F will further accelerate the build-up of lime scale on the heating surface and may shorten the
service life of the water heater. Failure of a heat exchanger due to lime scale build-up on the heating surface, low pH, or other chemical
imbalance IS NOT covered by the warranty.
Outlined below are water quality parameters which 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
measurement used in the U.S. 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, 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
o
scale build-up may result in premature failure of the heat exchanger. Operating temperatures above 135 F will further accelerate the
build-up of lime scale on the heating surface and may shorten the service life of the water heater.
Water that is classified as hard and very hard must be softened to avoid heat exchanger failure. See below for further information about
water hardness.
CLASSIFICATION MG/L OR PPM GRAINS/GAL
0 – 17.1
Soft 0 - 1
17.1 – 60 1 – 3.5
Slightly Hard
60 – 120 3.5 – 7.0
Moderately Hard
120 – 180 7.0 – 10.5
Hard
Very Hard 180 and over 10.5 and over
If the hardness of the water exceeds the maximum level of 7 grains per gallon, 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 7.0 is considered neutral. Water with a pH lower than 7 is considered acidic. Water pH higher than 7 is
considered alkaline. A neutral pH (around 7) is desirable for most potable water applications. Corrosion damage and heater failures
resulting from water pH levels of lower than 6 or higher than 8 ARE NOT covered by the warranty. The ideal pH range for water
used in a storage tank or a water heater system is 7.2 to 7.8.
WHL-001 REV. 9.3.14