Setting The Domestic Hot Water Parameters - Riello Condexa PRO NA 75P Installation, Operation And Service Manual

4.7.5 Setting the domestic hot water parameters

Parameter 35 defines the various operation modes of the boiler
for DHW production
Mode 0
(No production of domestic hot water)
In this mode the boiler will work only for the heating circuit (see
section "Setting the heating parameters and outdoor reset")
Mode 1
(DHW production with indirect storage tank and indirect tank sen-
sor)
In this mode, the boiler is activated when the temperature re-
corded by the indirect tank sensor falls below the DHW setpoint by
an amount equal to the hysteresis value and is deactivated when
the temperature rises above the DHW setpoint by the value of the
hysteresis.
The parameters that control DHW production are the following:
Par.
Description
No.
Defines the hysteresis to initiate the domestic hot water
36
demand.
Defines the hysteresis to stop the domestic hot water
37
demand.
Defines the primary circuit's set-point increase in de-
38 grees compared to the temperature set for the domestic
hot water tank.
Defines the primary circuit's restart hysteresis in modes
39 1 and 2 of DHW (valid both for cascade and stand-alone
applications).
Defines the primary circuit's shut-off hysteresis in modes
40 1 and 2 of DHW (valid both for cascade and stand-alone
applications).
48 Establishes the DHW storage tank set-point.
The setpoint value can be set directly, without entering the list of
parameters:
− Press MENU and select "Domestic Hot Water" using the ▲ /
▼ buttons.
Menu
" "
Central Heating (CH)
"
Domestic Hot Water (DHW)
"
Information
" "
Settings
" "
− Press the ● button to confirm.
Domestic Hot Water (DHW)
"
DHW Setpoint
" "
"
"
"
113.0 °F
" "
− Use the ► button to highlight the value, and use the ▲ / ▼
buttons to change the selected value. Press the ● button to
confirm/save the new settings.
The DHW value can be changed only when the "domestic hot wa-
ter" function is enabled. See section "Password access" for in-
structions about outdoor recovery.
Mode 2
(DHW production with indirect storage tank controlled by a ther-
mostat)
In this case the boiler is activated when the boiler's thermostat
contact is closed and is deactivated when the latter is opened.
The parameters that control DHW production are the following:
Par.
Description
No.
Defines the primary circuit's set-point increase in de-
38* grees compared to the temperature set for the domestic
hot water tank.
Defines the primary circuit's restart hysteresis in modes
39 1 and 2 of DHW (valid both for cascade and stand-alone
applications).
Defines the primary circuit's shut-off hysteresis in modes
40 1 and 2 of DHW (valid both for cascade and stand-alone
applications).
Defines the value referred to the Delta T of the tank for
maintenance purposes. E.g.: if it is set on 5.4 °F (3 °C),
when the tank has a set point lowered of 5.4 °F (3 °C),
41 the boiler turns on at the minimum to allow mainte-
nance until the set point plus hysteresis. If this parame-
ter is equal to parameter 36, this function is inactivated
and the boiler starts at the maximum sanitary power.
48 Establishes the DHW storage tank set-point.
(*) Parameter 38 is active on such mode even if the indirect
tank sensor is not installed and it influences the supply
temperature of the boiler.
It can be used to limit the difference between the actual supply
and set temperature on the indirect tank sensor so that the sys-
tem efficiency is maximized.
Also in this case,the setpoint value can be set directly, without en-
tering the parameters list, by accessing the "Domestic Hot Water"
menu, as mentioned earlier for mode 1.
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COMMISSIONING AND MAINTENANCE