State Water Heaters SCE 65-400, Installation, User And Service Manual

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Warm-up cycle of the appliance
Release R.1.0 Uk 15
gis
through the flue tubes
d
; flue baffles
e
are located in the flue tubes. These
delay the transport of the flue gases, which has the effect of improving
efficiency. The flue gases leave the appliance via the draught diverter
b
. A
radiation shield/condensation tray
k
is fitted under the burner tray. This
prevents overheating of the floor surface under the appliance and serves as a
collection tray for condensation water.
The PU insulation layer
f
prevents heat loss. The inside of the tank is
enamelled to protect against corrosion. The anodes
c
provide additional
protection. The Hydro Cannon also protects the bottom of the tank from furring.
2.3 Warm-up cycle of the
appliance
The complete appliance is controlled by the burner controller
t
and the control
thermostat
s
or frost thermostat
v
. The control thermostat and frost thermostat
both independently measure the water temperature (T
water
). The appliance's
warm-up cycle is activated as soon as T
water
falls below the threshold value
(T
set
). The value of T
set
depends on the selected state of the appliance, see
paragraph ’6.2 Operating states’ . If the appliance is in its 'OFF mode' (frost
protection) then this value is determined by the frost thermostat (threshold value
= 20°C). If the appliance is in its 'ON mode', then the threshold value can be set
via the control thermostat (±40°C - ±70°C).
As soon as T
water
falls below T
set
the (control or frost) thermostat in question
closes and the burner controller confirms a heat demand. The gas control
l
is
opened and the gas is mixed with air. This mixture is ignited with the glow
igniter
A
and the water is heated. As soon as T
water
rises above T
set
, the
thermostat opens once again. The heat demand is cancelled and the burner
controller stops the warm-up cycle.
The thermostats have a set margin both when closing and opening. This margin
is referred to as the hysteresis. The hysteresis cannot be adjusted.
2.4 Protecting the
appliance
The burner controller monitors the water temperature using thermostats and is
responsible for safe combustion. This takes place by:
•
the Water temperature protection ;
• the Flue gas outlet cut-out ;
• the Ionisation pin .
1. The gas flow is accelerated through the narrow opening in the injector. This creates a vacuum. Air
is also drawn in (Venturi effect) through the suction effect of this vacuum.