18
4 DESCRIPTION OF THE APPLIANCE
4.1
Characteristics
Murelle Revolution 30
is an innovative Ccass A++ wall-mounted
boiler designed by
Sime Ltd
SOLELY for space heating and pro-
ducing domestic hot water.
The appliance is made up of a latest-generation sealed con-
densing gas boiler and a heat pump.
Murelle Revolution 30
can ONLY operate if it is connected to
the outdoor probe supplied with the appliance; if the outdoor
probe is NOT connected,
Murelle Revolution 30
will NOT work.
The wall the appliance is mounted to must be able to support
its weight, and preferably be an outside wall, to simplify install-
ing the air inlet and outlet pipes.
Murelle Revolution 30
can produce water for a heating system
to a temperature of up to 75°C.
To obtain maximum performance
from
Murelle Revolution 30
, the delivery temperature
MUST NOT
exceed
65°C
and the return temperature must not be above of
45°C
.
The main design choices made by
Sime Ltd
for
Murelle Revolu-
tion 30
boilers are:
– use of a sealed boiler with a total pre-mix microflame burner
combined with a steel heat exchanger body and a rapid heat
exchanger for DHW
– use of a modulating circulation pump
– use of a heat pump (HP), which is supported by the boiler to
produce heat, and can operate separately or together with
the boiler, according to the temperature detected by the out-
door probe
– a Main control panel (remote) which serves both as an room
thermostat and as a command and control device, a micro-
processor, with bus protocol to manage the
Murelle Revolu-
tion 30
and related system
– use of a main evaporator with a patented smoke evaporator
in series and a plate heat exchanger to transmit the heat to
the water in the system. This allows the heat pump to oper-
ate with an average COP of 4.
– the option of being connected to room thermostats or
chrono-thermostats for the zone.
The command board also has an internal connection where an
expansion which can control the external relays can be insert-
ed.
Murelle Revolution 30
also has the following functions:
– the anti-freeze function which is activated automatically if
the temperature of the water inside the boiler falls below the
value set under “PAR 10” and if the outdoor temperature falls
below the value set under “PAR 11”
– anti jamming function of the pump and diverter valve, this
activates automatically every 24 hours if no request for heat
has been made
– the chimney sweep function lasts 15 minutes and makes the
job of the qualified technician easier when measuring the pa-
rameters and combustion efficiency
– domestic hot water comfort function which allows the time
necessary for the hot water to become available to be re-
duced and ensures that the temperature is stable
– screen display of the operating and self-diagnostic param-
eters with error code display when the fault occurs. This
makes repair interventions easier and allows appliance op-
eration to be restored correctly.
4.2
Operation summary
4.2.1
Heating
When there is a heating request from the main control panel
(MCP) or from an room thermostat for the zone (ATz), where
there are no alarms and where the outdoor temperature is at
least -7°C, the heat pump is activated (HP).
After a set period of time, calculated using an algorithm ac-
cording to the current outdoor temperature, the gas boiler also
starts up to help heat the water in the system and respond to
the current request for heat.
When the system water temperature reaches the required val-
ue, also calculated using a specific algorithm for the gas boiler,
the boiler stops and ONLY the heat pump continues to operate,
until the heating request has been satisfied; after which, the
heat pump also stops.
m
CAUTION
If, when there is a heating request, the outdoor tem-
perature is
below -7°C (e.g. - 10°C)
, only the gas boiler
is activated and the heat pump remains inactive.
4.2.2
Domestic Hot Water (DHW)
When there is a request for DHW, providing there is no heating
request from the room thermostats, the diverter valve prepares
to direct the flow of water towards the plate heat exchanger and
the boiler starts up to respond to the request.
Should there be a request for heat at the same time, the heat
pump stops and the boiler operates as described above. Once
the DHW request has been satisfied, standard heating opera-
tion resumes.
