Connection To Groundwater System: Electrical Connection; Connecting The Heat Pump To The Heating System - Bosch EHP 6-11 LW User And Installation Manual

Connection to groundwater system: electrical
connection
1. Connect the ground water pump to the mains via a motor cut-out and a
contactor. The control to the contactor (CK3) uses 230 V, which is taken
from the terminals L and N (P3) in the heat pump.
2. Connect the auxiliary contact for the motor cut-out MB3 in series with
the alarm input MB2. This method starts and stops the groundwater
pump with the heat pump's HTF pump. If the motor cut-out MB3 trips,
the heat pump stops and the alarm for the HTF pump is displayed on the
menu display.
Motor cut-out
Contactor
Groundwater pump
G8 (P8)
HTF pump G3 (P3)

Connecting the heat pump to the heating system

It is important that all previously mentioned preparations have been carried out
before the heat pump is connected to the heating system. Also ensure the pipe
system has been well fl ushed before it is connected to the heat pump. Flushing
protects the heat pump from contamination.
The heating system must be diffusion-proof. Oxygen must not enter the system.
The heat pump is only intended to work in oxygen free systems with so-called
"dead water". When oxygen enters the system this causes corrosion in the heat
pump and clogging of the fi lter on the heating system side. An intermediate heat
exchanger is necessary in systems with oxygen penetration/diffusion to protect
the heat pump.
Terminal card in
the heat pump
Alarm input
51
Connecting the heat pump to the heating system
Warning
If a single phase pump is used, it
should always be connected with
a contactor. It must never be con-
nected to the P3 output on the heat
pump as this can damage the control
unit.
Note
There is a built-in motor cut-out in
the pump on the 11-17 kW models.
Models 6-9 kW have a strap fi tted
between L and MB2 on the terminal
card.
Note
Only qualifi ed installers may carry out
the installation. The installer should
observe applicable regulations and
recommendations from the supplier.