A.O. Smith 100 Series, Руководство по обслуживанию

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Servicing should only be performed by a Qualified Service Agent
Water Connection
Heat Exchangers are equipped with 2 water male connections with NPT threading, according to the ANSI/ASME B1.20.1 standard,
which are sized according to the capacity of the heat exchanger.
Flue Gas Outlet Connection
The heat exchanger is equipped with an evacuation for the combustion products at the back side. Flue gas outlets are sized
according to the capacity of the heat exchanger.
A. O. Smith recommends the recovery and the evacuation of the flows coming from the chimney, mainly if there’s a risk of remains
in the chimney’s channel, in order to avoid that they return in the heat exchanger.
Burner Door/Plates Connection
A. O. Smith recommends that the burner doors should integrate a double tightness, a gasket insuring a thermal protection and a
gasket tight to the condensates and flue gas.
A. O. Smith recommends as well that the burner door should be itself in contact with the front panel of the heat exchanger in order to
limit the risk of leakage from combustion products in case of lack of remounting the gaskets.
Bolts on the front of the boiler/water heater can withstand forces resulting from the weight of the front panel and assembled parts
(burner door, fan, gas valve, venturi, air-gas sleeve). Maximum nuts torque for assembling the burner door is 3.7 ft.lb.
Operating Conditions - Installation factors
Heating units will be subject to the effects of corrosion from the moment they are filled with water. It is however essential that the
following installation factors are taken into account in order not to worsen the phenomenon of corrosion.
•
Combustion air must not contain chlorine, ammonia, or alkali agents. Installation of the product near a swimming pool, a washing
machine, or a laundry do expose combustion air to these contents.
• The heat exchanger must be used filled with water within the temperature and pressure limits specified in its technical specification
booklet.
• The water's pH must fall within the following limits: 7.5<pH<9.5 and if the system contains aluminium parts, it must be less
than 8.5. This pH value is achievable after steady state conditions after filling the mains network water (pH around 7) inside the
installation and the air bleeding operation has been done ( death water condition).
• Water hardness must fall within the following limits:
• 5°F<TH<15°F
• 3 Grains/US gallon<TH<9 Grains/US gallon
• To avoid to the maximum presence of oxygen in the system, it is advised to prevent as much as possible air intake and water
leakage during installation. Usual spots where air is most likely to seep in are: suction gasket, pump, air valve working as venting
pipe, O-rings gaskets in stuffing box. Using an automatic water refill system reduces some risk (as any fresh water is bringing
fresh oxygen in the system), like installing a water meter so that it is possible to evaluate the water volume in order to eliminate
any water leakage as early as possible.
• A minimum water pressure, adapted to each exchanger type, is requested in order to allow good performances.
• A. O. Smith recommends to the customers to carry out the drain of the heat exchanger after test or use in order to avoid
consequences on the product in the event of freezing ; the expansion of the water in case of freezing could cause degradations
or leakages.