Operation; Domestic Hot Water Mode; Central Heating Mode - Chaffoteaux & Maury Britony SE 80 Nat Operating Instructions Manual

5

Operation

29

Domestic Hot Water Mode

In order to supply hot water, the main switch 19 Fig. 6
must be in ON position I This will be confirmed by the
green indicator light 23 Fig. 6. Turn the selector switch
20 clock wise to establish the green DHW indicator 28 Fig. 6.
When a tap or shower is turned on, the flow of mains
water, above 2 litres per min., will activate the 3 way valve
f Fig. 7 to move to the DHW position. The pump will now
circulate primary water heated by the main heat exchanger
through the secondary heat exchanger.
The first stage solenoid a Fig. 7 and safety solenoid c
Fig. 7 open together to allow gas to the burner. The
ignition sequence begins and a continuous high speed
spark ignites the gas. As soon as a flame is detected the
orange indicator bulb 24 Fig. 6 will light and the second
a b c
d
e
Fig. 7
25
26 22
reset
21
f
24 23
20
stage solenoid b Fig. 7 opens to allow the full gas rate. If a
flame is not detected, after 8 seconds, the security
solenoid closes and shuts off the gas. The red lockout
indicator bulb 25 Fig. 6 will show. The domestic hot
water temperature is controlled by the hot water control
thermistor d Fig. 7 and the central heating control
thermistor e Fig. 7. This system anticipates the changes of
temperature in the secondary heat exchanger and ensures
accurate temperature regulation.
When the tap is closed the burner is extinguished and the
pump stops.
Priority will be given to a demand for hot water. This will
interrupt the central heating for the duration of hot water
delivery.

Central Heating Mode

To be able to supply heating, the main switch 19 Fig. 6 must
be in I position. This will be confirmed by the green indicator
light 23 Fig. 6. Turn the selector switch 21 clock wise to
establish the green heating indicator 29 Fig. 6.
When there is a demand for heating (either from the room
thermostat or the clock) and the boiler temperature control is
calling for heat. The pump starts allowing the ignition
sequence to begin. The first stage solenoid a Fig. 7 and
safety solenoid c Fig. 7 open together to allow gas to the
burner. The ignition sequence begins and a continuous high
speed spark ignites the gas. As soon as a flame is detected
the orange indicator bulb
seconds the second stage solenoid b Fig. 7 opens to allow
the full gas rate. If a flame is not detected, after 8 seconds,
the security solenoid closes and shuts off the gas. The red
lockout indicator bulb 25 Fig. 6 will show.
The central heating flow temperature is controlled by the
central heating control thermistor e Fig. 7. The boiler has
been designed to minimise cycling and will not attempt to
relight for at least 3 minutes after the boiler thermostat has
been satisfied (it is possible to reduce the time to 30 s if
necessary). When the room thermostat is satisfied the
burner will switch off and the pump will remain running for a
further 4 minutes before it to stops.
NB : It is possible to override the 3 minute delay by pressing
the RESET button 26 Fig. 6.
28
I
Fig. 6
19
24 Fig. 6 will light. After 45
7