20
FAMILY CX
REQUEST FROM ROOM THERMOSTAT OR POR
(Heating Programming Timing)
In this case the outlet setpoint depends on the outdoor temperature for
obtaining a reference ambient temperature of 20°C.
There are 2 parameters that compete to calculate the output setpoint:
- slope of the compensation curve (KT)
- offset on the reference ambient temperature.
SELECTING THE COMPENSATION CURVE- (Fig. 20)
The compensation curve for heating maintains a theoretical temperature of
20°C indoors, when the outdoor temperature is b20°C and -20°C.
The choice of the curve depends on the minimum outdoor temperature
envisaged (and therefore on the geographical location), and on the delivery
temperature envisaged (and therefore on the type of system). It is carefully
calculated by the installer on the basis of the following formula:
KT = T.outlet envisaged - Tshift
20- min. design external T
Tshift = 30°C standard system
25°C floor installations
If the calculation produces an intermediate value between two curves, you
are advised to choose the compensation curve nearest the value obtained.
Example
: if the value obtained from the calculation is 1.3, this is between
curve 1 and curve 1.5. Choose the nearest curve, i.e. 1.5.
The settable KT values are as follows:
Standard system: 1.0-3.0
floor system 0.2-0.8.
Using the REC10 it is possible to set the selected thermoregulation curve:
- access the technical parameters as explained in the section“ Accessing
the technical parameters”.
- in sequence select THERMOREGULATION and CLIMATIC CURVES
with the “
UP
” and “
DOWN
” keys, confirming the selection
- select the desired heating zone with the “
UP
” and “
DOWN
”, keys
confirming the selection
- set the desired climatic curve with the “
UP
” and “
DOWN
” keys, confirming
the selection.
OFFSET ON THE REFERENCE AMBIENT TEMPERATURE - (Fig. 20)
In any event, the user can indirectly modify the value of the HEATING
setpoint inserting an offset on the reference temperature that can vary
within the range -5-+5 (offset 0 = 20°C).
NIGHT COMPENSATION - (Fig. 20)
Whenever a programmable timer is connected to the ROOM THERMOSTAT
input, from the TECHNICAL\THERMOREGULATION\CLIMATIC CURVES\
MAIN the NIGHT COMPENSATION function can be enabled.
In this case, when the CONTACT is CLOSED, the heat request is made
by the flow sensor, on the basis of the outdoor temperature, to obtain a
nominal ambient temperature on DAY level (20°C).
The opening of the contact does not produce a switch-off, but a reduction
(parallel translation) of the climatic curve on NIGHT level (16°C).
Also in this case, the user can indirectly modify the value of the HEATING
setpoint inserting once again an offset on the reference DAY temperature
(20°C) rather than NIGHT (16°C) that can vary within the range [-5 - +5].
5.3
First commissioning
- Position the system's master switch to the "on" position.
- Open the gas tap to allow fuel to flow.
- Adjust the room thermostat to the desired temperature (~20°C) or, if the
system is equipped with a chronothermostat or programmable timer or
REC10 set as an ambient regulator, ensure that the thermostat or timer
is "active" and set correctly (~20°C)
- Then set the boiler for WINTER selecting the status menu on the REC10
and then BOILER, based on the season and the type of operation
selected.
42
°C
MENU
STATE
SET
INFO
PLANT
HOT WATER TEMPERATURE
FRI
1.3
bar
18/05/2013
12:17
BOILER
MAIN ZONE
STATE
OFF
HOT WATER ONLY
HEATING AND HOT WATER
BOILER
- When there is a heat request and the boiler is igniting, the icon “ ” appears
on the display. The boiler will start up and continue working until the set
temperatures are reached, after which it will then go back to standby.
Vent cycle
b
Each time that the boiler is powered, an automatic vent cycle is
carried out lasting 4 min. When the vent cycle is in progress, all heat
requests are inhibited except for domestic hot water ones when the
boiler is not set to OFF, and a scrolling message at the foot of the
page appears on the main page of the REC10.
X17
X14
1
5
6
X6
1
3
1
X3
X7
SW1
combustion analysis button SW1
b
The vent cycle can be interrupted beforehand by removing the cap
from the instrument panel and pressing the combustion analysis
button SW1 or else from the TECHNICAL menu of the REC10 in the
following way:
