andrews MAXXflo EVO CWH 30/201 Operating Instructions Manual page 39

4.5 COMPLETE PARAMETER LIST TABLE (CONTINuEd)
PARAMETER DESCRIPTION
dHW (continued)
1660 Pump release
dHW release
With this parameterization, the circulating
pump is released when DHW heating
is released also.
1661 Pump cycling
1663 Circulation setpoint
Boiler
2300 Frost protection for plant
boiler pump
dHW Storage tank
5012 DHW forced charging
5020 DHW setpoint boost
5024 DHW switching differential
Engineer
FACTORY NOTES
DEFAULT
Time pro- Set desired option for activation of the DHW circulation pump
gramme 5 (see below)
Time program 4/dHW
The circulating pump is released accord-
ing to time program 4 / DHW.
Off When switched on, the circulation pump will cycle on and off
during the activation period (on for 10 minutes then off for 20
minutes repeatedly).
Where B39 sensor has been installed this function will
become active only once the circulation setpoint has been
achieved.
45 C When B39 sensor is installed on the DHW distribution return
o
pipe, the heater controller will monitor the return temperature
during the activation time of the pump. Whenever the tem-
perature acquired by the sensor falls below the circulation
setpoint, the pump will be active until the setpoint has been
exceeded (minimum pump run time is 10 minutes).
During a legionella cycle operation the temperature at the
sensor can be used to adjust the dwell time, ensuring that
the entire DHW system reaches the legionella setpoint for
the total dwell time length set. The dwell time counter is not
started until the temperature at the sensor reaches legionella
setpoint.
On When turned on the pump is activated when the temperature
in the heat exchanger drops below 5
On The first charge activation of the day is calculated using a
switching differential of 1
rameter 5024
0 C Used by the control strategy to calculate the internal flow
o
temperature required to raise the actual water temperature to
the DHW set point.
Examples:
A boost of 2
draw off temperature could be 2
Burner efficiency will decrease slightly with a higher boost.
A boost of -2
water draw off temperature will be at no higher than tank
setpoint. Burner efficiency will increase slightly with a lower
boost.
2 C Defines by how much the temperature of the water in the
O
DHW tank can drop below set point before recharging takes
place. This differential applies both to the Nominal as well as
the Reduced DHW tank setpoint
39
Time program 5
The circulating pump is released accord-
ing to independent time program 5.
C
O
C regardless of the setting of pa-
O
C will reduce the re-charging time ,but the water
O
C above the tank setpoint.
O
C will increase the re-charging time ,but the
O
MAXXflo EVO