State Water Heaters PRV 30 NORS G, Инструкция по установке и эксплуатации

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4
1. GENERAL
1.1 Introduction
Construction of the heaters is in
accordance with the European
standard for gas heated water storage
heaters for sanitary application (EN 89).
The appliance thus meets the European
Directory for Gas Appliances and is
therefore entitled to carry the CE-
marking.
It is an open flue appliance without a
fan and with a flue gas down draught
safeguard (category B
11BS
). The water
heater is suitable for a maximum
working pressure of 8 bar. The heater
tank is manufactured from low carbon
sheet steel and is glass-lined on the
inside. In addition the tank is fitted with a
sacrificial anode as an extra protection
against corrosion. A thick 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. A flue
baffle has been placed in the flue tube
to improve heat transfer. The flue
gasses pass their heat on to the water
by means of radiation and convection.
The flue gasses are guided to the
chimney via the draught diverter. The
exhaust of the flue gasses is realized
by natural thermal draught (see
Figure1).
Dead legs on a hot water installation are
undesireable. Where possible they
should be avoided. Where the inclusion
on the system of a dead leg is
unavoidable the following restrictions
should be applied:
-
for pipes not exceeding 19 mm.
inside diameter; maximum lengh of
dead leg permitted 12.0 metres;
- for pipes exceeding 19 mm. but not
exceeding 25 mm. inside diameter;
maximum length of dead leg 7.5
metres;
- for pipes with an inside diameter
exceeding 25 mm. maximum dead leg
3.0 metres.