General, Description of the appliance | A.O. Smith BTI 85 G guide

1. GENERAL

1.1Description of the appliance

Construction of the water heater is in accordance with the European standard for gas heated water storage heaters for sanitary application (EN89). The appliance thus meets the European Directory for Gas Appliances and is therefore entitled to carry the CE- marking. It is an open flued appliance without ventilator and with a flue gas down draught safeguard, a Thermal Reflux Safeguard (TRS) (category

B11BS). The water heater is suitable for a maximum working pressure of 8 bar.

The water heater tank is manufactured from low carbon sheet steel and is glasslined on the inside. In addition the tank is fitted with a magenesium anode as extra protection against corrosion. A thick, CFC-free, PU insulation layer covered in a steel jacket reduces unnecessary heat loss. When the appliance is filled with water it continuously is under water pressure. As hot water is drained from the tank, cold water is added immediately. Four flue baffles have been placed in the flue tube to improve heat tranfer. The flue gasses pass their heat on to the water by means of radiation and convection. The exhaust of the flue gasses is realized by natural thermal draught (see figur 1).

Dead legs on a hot water installation are undesireable. Where possible they should be avoided. When the inclusion on the system of a dead leg is unavoidable the following restrictions should be applied:

-for pipes not eceeding 19 mm. inside diameter; maximum length of dead leg permitted 12 metres;

-for pipes exceeding19 mm. but not exceeding 25 mm. inside diameter; maximum lenght of dead leg 7,5 metres;

-for pipes with an inside diameter

exceeding 25 mm. maximum length of dead leg 3 metres.