A.O. Smith 197835-001 Manuel D’Utilisation

13

Water supply systems may, because of code requirements or such

conditions as high line pressure, among others, have installed devices

such as pressure reducing valves, check valves, and back flow preventers.

Devices such as these cause the water system to be a closed system.

As water is heated, it expands (thermal expansion). In a closed system

the volume of water will grow when it is heated. As the volume of water

grows there will be a corresponding increase in water pressure due

to thermal expansion. Thermal expansion can cause premature tank

failure (leakage). This type of failure is not covered under the limited

warranty. Thermal expansion can also cause intermittent temperature-

pressure relief valve operation: water discharged from the valve due to

excessive pressure build up. The temperature-pressure relief valve is

not intended for the constant relief of thermal expansion. This condition

is not covered under the limited warranty.

A  properly  sized  thermal  expansion  tank  should  be  installed

on  all  closed  systems  to  control  the  harmful  effects  of  thermal

expansion..

note:  to  protect  against  untimely  corrosion  of  hot  and  cold 

CORROSION OF THE FLUEWAYS AND VENT SYSTEM MAY OCCUR IF 

AIR FOR COMBUSTION CONTAINS CERTAIN CHEMICAL VAPORS. SUCH 

CORROSION MAY RESULT IN FAILURE AND RISK OF ASPHYXIATION.
Spray  can  propellants,  cleaning  solvents,  refrigerator  and  air

conditioning  refrigerants,  swimming  pool  chemicals,  calcium  and

sodium chloride (water softener salt), waxes, and process chemicals

are typical compounds which are potentially corrosive.
Do not store products of this sort near the heater. Also, air which is

brought  in  contact  with  the  heater  should  not  contain  any  of  these

chemicals. If necessary, uncontaminated air should be obtained from

remote or outside sources. The limited warranty is voided when failure

of water heater is due to a corrosive atmosphere. (See limited warranty

for complete terms and conditions).

HOTTER  WATER  CAN  SCALD: 

Water heaters are intended to produce hot water. Water heated to a

temperature which will satisfy space heating, clothes washing, dish

washing, cleaning and other sanitizing needs can scald and permanently

injure you upon contact. Some people are more likely to be permanently

injured by hot water than others. These include the elderly, children, the

physically or developmentally disabled. If anyone using hot water fits into

one of these groups or if there is a local code or state law requiring a

certain temperature water at the hot water tap, then you must take special

precautions. In addition to using the lowest possible temperature setting

that satisfies your hot water needs, a means such as a *mixing valve,

should be used at the hot water taps used by these people or at the water

heater, see Figure 2. Valves for reducing point of use temperature by

mixing cold and hot water are also available:

 

Consult a Qualified Installer or Service Agency. Follow manufacturer’s

instructions for installation of the valves. Before changing the factory

setting on the thermostat, read the “Temperature Regulation” section in

this manual.

This water heater should not be connected to any heating systems or

component(s) used with a non-potable water heating appliance.
All  piping  components  connected  to  this  unit  for  space  heating

applications should be suitable for use with potable water.
Toxic chemicals, such as those used for boiler treatment should not be

introduced into this system.
When the system requires water for space heating at temperatures

higher than required for domestic water purposes, a mixing valve must be

installed. Please refer to Figure 2 for suggested piping arrangement.