Heating System Connection; Frost Protection - Dimplex LI 11TES Instructions D'installation Et D'utilisation

LI 11TES - LI 16TES

7.3 Heating system connection

The heating system connections on the heat pump have a 1¼"
external thread. A spanner must be used to firmly grip the
transitions when connecting the heat pump.
Before connecting the heating water system to the heat pump,
the heating system must be flushed to remove any impurities,
residue from sealants, etc. Any accumulation of deposits in the
liquefier may cause the heat pump to completely break down.
For systems in which the heating water flow can be turned off
using radiator and/or thermostat valves, an overflow valve must
be installed by the customer in a heating bypass upstream from
the heating pump. This ensures a minimum heating water flow
rate through the heat pump and helps to avoid faults.
Once the heat pump has been connected to the heating system,
it must be filled, de-aerated and pressure-tested.
The following points must be observed when filling the system:
 Untreated filling water and make-up water must be of
drinking water quality
(colourless, clear, free from sediments)
 Filling water and make-up water must be pre-filtered (max.
pore size 5µm).
Scale formation in domestic hot water heating systems cannot be
completely avoided, but in systems with flow temperatures below
60°C, the problem can be disregarded.
With medium and high-temperature heat pumps, even
temperatures above 60 °C can be reached.
The following standard values should therefore be adhered to
regarding the filling and make-up water according to VDI 2035,
sheet 1:
Total alkaline earths
Total heat
in mol/m³ and/or
output in [kW]
mmol/l

up to 200

200 to 600
> 600 < 0.02
Minimum heating water flow
The minimum heating water flow through the heat pump must be
assured in all operating states of the heating system. This can be
accomplished, for example, by installing either a dual differential
pressureless manifold or an overflow valve. The procedure for
setting an overflow valve is described in the chapter „Start-up".
When the minimum flow rate is undershot, the plate steel ex-
changer in the refrigerating cycle can freeze, which can lead to
total loss of the heat pump.
ATTENTION!
The use of an overflow valve is only recommended for panel heating and
a maximum heating water flow of 1.3 m³/h. System faults may result if this
is not observed.
EN-8
Total
hardness in °dH

2.0 11.2

1.5 8.4
< 0.11
452161.66.03 · FD 9303

Frost protection

A method of manual drainage (see illustration) should be
provided for heat pumps which are exposed to frost. The frost
protection function of the heat pump manager is active whenever
the heat pump manager and the heat circulating pump are ready
for operation. The system has to be drained if the heat pump is
taken out of service or if a power failure occurs. If heat pump
systems are implemented in buildings where a power failure
cannot be detected (holiday homes etc.), the heating circuit
should be operated with suitable frost protection.
www.dimplex.de