REMEHA Celcia MC4, Installation And User Manual

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Remeha Celcia MC4
LT.AL.REM.000.016
LT.AL.REM.000.028
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No sequential regulators are to be coupled to the Celcia MC4,
as in a mixing group, swimming pool or boiler regulation, for
example. The tap water system is regulated via the control unit
of one of the boilers.
Mounting the outside temperature sensor:
Mount the outside sensor, protected against direct sunlight,
on the north or northwest side of the building, at a height of
2.5 metres min. from ground level. Do not mount the outside
temperature sensor close to windows, doors, ventilation grids
or exhaust covers, etc.
2.2.5 Principle diagram of the connection of system
components
Ba = Outside temperature sensor
Bv = System flow temperature sensor
U = System pump
Hw = Low loss header
2.2.6 Choice of boilers
All boilers in the cascade system should have OpenTherm
communication.

For correct cascade regulation, the ratio between the powers
of the largest and smallest boilers may not be more than 2.5.
A good combination is, for example: 40 kW + 80 kW + 80 kW
(80 : 40 = 2 is < 2.5; i.e. good)
A bad combination is, for example: 40 kW + 40 kW + 120 kW
(120 : 40 = 3 is > 2.5; i.e. bad)
2.3 Putting into Operation
2.3.1 Operation
The operation of the Celcia MC4 contains one function key for
the automatic configuration and LED indications.
1 = ‘autoconfig’ button
2 = status LED
3 = thermostat LED
4 - 7 = boiler LEDs
8
= system flow temperature sensor LED
9 = outside temperature sensor LED
10 = pump LED
11 = failure relay LED