Primary Pump Command

On initial start-up or after power failure, the pump will be enabled after a delay defined by parameter PRP-01.

The pump starts if one or more of the following conditions are true:

The calculated DHW setpoint condition includes normal, extended and legionella operation. Stopping the pump will always occur after a delay defined by parameter PRP-02.

Programming Hint

Connect a flow switch only for continuous-flow or tankless heater applications. For applications with single domestic hot water heat exchanger connected to a DHW tank, set the "CircPumpDemand" input to the value "1"

Start-up Hint

Take care that the primary pump always starts earlier than the secondary pump. The primary pump start-up delay must be shorter than the secondary pump start-up delay in order to assure that the heat is not accumulated in the heat exchanger.
The secondary pump must stop later than the primary pump.

Table 9.   Parameter List

Description

Value Range

Default Value

Unit

PRP-01: primary pump start-up delay

0...600

0

sec

PRP-02: primary pump switch off delay

0...1200

5

sec