HTP PHR199-55C - Manual (Page 56)

56
LP- 325 REV. 3.21.14
Water Hardness
Water hardness is mainly due to the presence of calcium and magnesium salts dissolved in the water. The concentration of these salts
is expressed in mg/L, ppm or grains per gallon, as a measure of relative hardness of water. 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 when the water is heated and cause accelerated lime and scale accumulation on a heat transfer surface.
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 appliance
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.
Total Dissolved Solids
Total Dissolved Solids (TDS) is a measurement of all minerals and solids dissolved in a water sample. The concentration of total
dissolved solids 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 on the heat transfer surface that will
greatly reduce the service life of a water heater. This scale accumulation can also impede the ability of the heat exchanger to transfer
heat into the water. A heat exchanger damaged or blocked by lime/scale accumulation must be replaced.
The manufacturer of the appliance has no control of water quality, especially TDS levels in your system. Total dissolved solids in
excess of 2,000 ppm will accelerate lime and scale formation in the heat exchanger. Heat exchanger failure due to total dissolved solids
in excess of 2,000 ppm is a non-warrantable condition. Failure of an appliance due to lime scale build up on the heating surface IS
NOT covered by the warranty.
Hardness: 7 grains
Chloride levels: 100 ppm
pH levels: 6-8
TDS: 2000 ppm
Sodium: 20 mGL
D. FREEZE PROTECTION (WHEN USED)
NEVER use automotive or standard glycol antifreeze. Do not use ethylene glycol made for hydronic systems. System water, including
additives, must be non-toxic, having a toxicity rating or Class of 1, as listed in Clinical Toxicology of Commercial Products. Use only
freeze-protection fluids certified by fluid manufacturer
as suitable for use with stainless steel boilers, verified in the fluid manufacturer’s
literature. Thoroughly clean and flush any system that has used glycol before installing the new boiler. Provide the boiler owner with a
material safety data sheet (MSDS) on the fluid used.
1. Determine freeze protection fluid quantity following fluid manufacturer instructions. Remember to include expansion tank water
content.
2. Local codes may require back flow preventer or disconnect from city water supply.
3. When using freeze protection fluid with automatic fill, install a meter to monitor water makeup. Freeze protection fluid may leak
before water begins to leak, causing concentration to drop, reducing the freeze protection level.
Test / replace freeze protection fluid
1. Follow fluid manufacturer instructions to verify inhibitor level and other fluid characteristics are satisfactory.
2. Freeze protection fluid must be replaced periodically due to degradation of inhibitors over time. Follow all fluid manufacturer
instructions.