Connecting To The Heating System Without A Bypass - IVT Greenline HT Plus C Assembly, Commissioning And Maintenance Manual

Connecting the heat pump to the heating system

Connecting to the heating system without a bypass:

The heat pump can be connected to the heating system without a bypass, as the circulation in the heat pump and the
heating system is managed by the integrated pump G2 (P2). This also means the main pump G1 (P1) is omitted. An
absolute prerequisite for the connection is that a minimum fl ow of at least 70% of the nominal fl ow (see the
table below) can be maintained throughout the year The thermostat valves in the heating system should be fully open
and in a fl oor heating system, it is necessary for at least half of the coils to be fully open.
The control unit gives an alarm when the temperature increase exceeds 13ºC in the heating system. If the heating system
is designed so that a minimum fl ow cannot be guaranteed, the heat pump should be connected using a bypass and an
external main pump G1 (P1).
Hot water function:
Hot water charging is started by the hot water sensor T3 (GT3), and is stopped by the return sensor T9 (GT9).
Circulation pump
In heat pumps from 6 to 11 kW the circulation pump G2 (P2) is a Wilo Star 25/6-130.
In heat pups from 14 to 17 kW the circulation pump G2 (P2) is a Wilo TOP-S 25/7.5 EM.
The pump curves apply for water +20ºC.
Maximum external pressure drop in the heating system
The maximum external pressure drop and the minimum fl ow that the integrated
circulation pump can handle is presented in the table. If the minimum fl ow cannot
be guaranteed a bypass and an external main pump G1 (P1) should be installed.
Heat pump Nominal fl ow
C6/E6
C7/E7
C9/E9
C11/E11
E14
E17
Flow (Q)
Minimum fl ow
0.20 l/s 0.14 l/s
0.25 l/s 0.18 l/s
0.31 l/s 0.22 l/s
0.38 l/s 0.26 l/s
0.50 l/s 0.35 l/s
0.57 l/s 0.40 l/s
Max external pressure
drop
36.0 kPa
36.0 kPa
34.0 kPa
32.0 kPa
54.0 kPa
51.0 kPa
52