Heating System Connection - Dimplex LAK 3IMR Installation And Operating Instruction

LAK 3IMR - LAK 14ITR
5.3

Heating system connection

The heating system connections on the indoor unit have a 1" flat
sealing external thread. A spanner must be used to firmly grip the
transitions when making the connections.
There is a hose sleeve on the safety valve for on-site connection
of a plastic hose. This should be fed into a siphon or outflow.
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.
Once the heat pump has been connected to the heating system,
it must be filled, purged and pressure-tested.
The following points must be observed when filling the system:
 Untreated filling water and make-up water must be of drink-
ing water quality
(colourless, clear, free of sediments)
 Filling water and make-up water must be pre-filtered (max.
pore size 6 µm).
Scale formation in domestic hot water heating systems cannot be
avoided, but in systems with flow temperatures below 60 °C, the
problem can be disregarded. With high-temperature heat pumps
and in particular with bivalent systems in the higher performance
range (heat pump + boiler combination), flow temperatures of
60 °C and more can be achieved. The following standard values
should therefore be adhered to with regard to the filling and
make-up water according to VDI 2035, sheet 1: The total hard-
ness values can be found in the table.
Total alkaline
Total heat
earths in mol/m³
output in kW
and/or mmol/l
< 50 ≤ 2.0
≤ 2.0
50 - 200
≤ 1.5
200 - 600
> 600 < 0.02
1. This value lies outside the permissible value for heat exchangers in heat
pumps.
Fig. 5.1:Guideline values for filling and make-up water in accordance with
VDI 2035
For systems with an above-average specific system volume of
50 l/kW, VDI 2035 recommends using fully demineralized water
and a pH stabiliser to minimize the risk of corrosion in the heat
pump and the heating system.
ATTENTION!
With fully demineralized water, it is important to ensure that the minimum
permissible pH value of 7.5 (minimum permissible value for copper) is
complied with. Failure to comply with this value can result in the heat
pump being destroyed.
NOTE
If the unit is connected to an existing hydraulic water circuit, the
hydraulic pipes must be cleaned to remove residues and limescale.
The heating circuit must include a corresponding purging facility,
a fill and drain valve and a dirt trap on-site.
It is also recommended to install a shut-off device in the return
before integration into the indoor unit is carried out.
www.dimplex.de
Specific system volume
(VDI 2035) in l/kW
≥ 20 < 50 ≥ 50
< 20
Total hardness in °dH
≤ 16.8 ≤ 11.2
≤ 11.2 ≤ 8.4
1
< 0.11
≤ 8.4
1
< 0.11
1
< 0.11
452162.66.09 · FD 9703
Minimum heating water flow rate
The minimum heating water flow rate must be ensured in all op-
erating states of the heating system with at least 50 l (buffer tank
with individual room control or underfloor heating system with
50 l minimum volume in open heating circuits). When the mini-
mum heating water flow rate is undershot, the plate heat ex-
changer in the refrigeration circuit can freeze, which can lead to
total loss of the heat pump.
The nominal flow rate is specified depending on the max. flow
temperature in the device information and must be taken into ac-
count during planning. With design temperatures below 30 °C in
the flow, the design must be based on the max. volume flow with
5 K spread for A7/W35.
The specified nominal flow rate (See "Device information" on
page 18.) must be assured in all operating states. An installed
flow rate switch is used only for switching off the heat pump in the
event of an unusual and abrupt drop in the heating water flow
rate and not to monitor and safeguard the nominal flow rate.
Frost protection
A method of manual drainage must be provided for heat pump in-
ternal components which are exposed to frost. The frost protec-
tion 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. The hydraulic
network should be operated with suitable frost protection if heat
pump systems are implemented in buildings where a power fail-
ure cannot be detected (vacation homes etc.).
NOTE
Chemical treatment to protect from rust should be carried out by the
installer.
English
EN-7