Ravenheat RSF 82E, Installation And Servicing Instructions

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2.4
2.4.1
2.4.2
2.4.3
Domestic hot water mode 2.4.4
The heat exchanger in the D.H.W. circuit is
built into the main heat exchanger, and
domestic water is heated by converting the
water in the central heating circuit. The
transference of heat is very high because
the two fluids move in a counter direction
flow to each other.
Switch 33 in the (winter) position.
When a hot water tap is turned on a
diaphragm diverter valve excludes the cen-
tral heating circuit the boiler automatically
modulates to maintain the domestic hot
water at a constant temperature.
Water temperature can be regulated using
the D.H.W. thermostat located on the front
control panel.
When domestic hot water is being drawn the
main burner and pump perform as they do
during central heating except that the burner
is commanded by the D.H.W. thermostat.
2.4.5
3.1
OVERALL DIMENSION
3.1.2
Fig. 3
When D.H.W. is no longer called for the boil-
er automatically returns to the central heat-
ing mode.
Switch 33 in the (summer) position. The
boiler functions like an automatic gas hot
water heater. When D.H.W. is no longer
required the main burner, fan and pump
immediately turn off.
This also takes place when switch 33 is on
(winter) if there is no demand for
heat to the central heating system or until
the room thermostat/time clock demands for
heat to the central heating circuit.
SAFETY DEVICE
In both central heating and domestic hot
water mode safe operating is ensured by:
- A differential pressure switch which shuts
off the main burner if the fan stops or the flue
or combustion air intake duct is obstructed.
An overheat cut off thermostat set slightly
higher than the high limit thermostat acts to
turn off the burner to resetable “lockout”
(Fig. 50 item 3).
3.1.3
A safety valve fitted on the
central heating circuit set at
43 psi (3 bar).
3.2.1 A heating circuit (low water)
pressure switch is set at 0.4
bar.