Functions

ES 5941Z

6.7.2 Circulation support

Function

Hold time/interruption

6.8

Recharging primary

Recharging/heat request

Function

Setpoint

If activation occurs via the time program LEG05 THM.DISINF.TIMEPRO-

GRAM, the circulation pump is activated and the station control is

deactivated. Monitoring and safeguarding of the temperature must be

done externally.

This mode is maintained for the duration of the defined time slot. The

circulation pump is only stopped if the domestic hot water tempera-

ture is

> BAS02 DHW MAX TEMP. FRIWA returns to normal control mode

once the time slot has elapsed.

Request for heat on the primary side, with an additional sensor in the

heat source:

If the temperature at the tank top sensor TO1 is lower than the cur-

rent setpoint PRI02 TANK TOP SETPOINT TEMP, recharging is activated

or heat is requested. If the current setpoint plus NAC03 SWITCH ON

RECHARCHING is exceeded at the tank top sensor TO1, recharging is

blocked or the heat request is cancelled. Recharging can also be

restricted via a time program.

n T1O < T1Oset, then NALAD active.

n T1O> T1Oset + NAC03 SWITCH ON RECHARGING, then NALAD

blocked.

n T1Oset (normal operation) = BAS01 DHW TEMP.SETPOINT + DIFF.

n T1Oset (legionella protection) = LEG01 TEMP TERM. DISINFECTION +

DIFF.

If there is active communication in the eBUS network, the recharging

setpoint relayed is PRI02 TANK TOP SETPOINT TEMP plus 5 K.

Dynamic temperature difference

DIFF is a dynamically calculated temperature differ-

ence that is required between the primary and sec-

ondary side of the plate heat exchanger in order to

reach the desired domestic hot water temperature at

the current flow rate.

Communication

03/2024 Item no. 215790 EA no. 1321

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