Dimplex WI 120TU, Инструкция по установке и эксплуатации

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www.gdts.one 452237.66.53 · FD 9912 EN-11
WI 120TU - WI 180TU English
9 Cleaning / maintenance
9.1 Maintenance
To prevent faults due to sediment in the heat exchangers, care
must be taken to ensure that no impurities can enter either the
heat source system or the heating system. In the event that op-
erating malfunctions due to contamination occur nevertheless,
the system should be cleaned as described below.
9.2 Cleaning the heating system
The ingress of oxygen into the heating water circuit may result
in the formation of oxidation products (rust), particularly if steel
components are used. These enter the heating system via the
valves, the circulating pumps and/or plastic pipes. A diffusion-
resistant installation is therefore essential, especially with re-
gard to the piping of underfloor heating systems.
NOTE
º
We recommend the installation of a suitable corrosion
protection system to prevent the formation of deposits (e.g.
rust) in the condenser of the heat pump.
Residue from lubricants and sealants may also contaminate the
heating water.
In the event of severe contamination leading to a reduction in
the performance of the liquefier in the heat pump, the system
must be cleaned by a heating technician.
Based on current information, we recommend using a 5 %
phosphoric acid solution for cleaning purposes. However, if
cleaning needs to be performed more frequently, a 5 % formic
acid solution should be used.
In both cases, the cleaning fluid should be at room tempera-
ture. We recommend flushing the heat exchanger in the direc-
tion opposite to the normal flow direction.
To prevent acidic cleaning agents from entering the heating
system circuit, we recommend connecting the flushing device
directly to the flow and return of the liquefier of the heat pump.
It is then important that the system be thoroughly flushed using
appropriate neutralising agents to prevent any damage from
being caused by cleaning agent residue remaining in the sys-
tem.
Acids must be used with care and the regulations of the em-
ployers liability insurance associations must be adhered to.
The instructions of the cleaning agent manufacturer must al-
ways be observed.
9.3 Cleaning the heat source
system
ATTENTION!
!!
The supplied dirt trap must be inserted in the heat source inlet
of the heat pump to protect the evaporator against the ingress
of impurities.
The filter sieve of the dirt trap should be cleaned one day after
start-up. Further checks must be set according to the level of
dirt. If no more signs of contamination are evident, the filter can
be removed to reduce pressure drops.
9.4 Water quality requirements
Irrespective of any legal regulations, the ground water should
not contain any substances that could form deposits. Iron
(< 0.2 mg/l) and Manganese (< 0.1 mg/l) limit values must be
adhered to to prevent iron ochre sedimentation from forming in
the heat source system.
The use of surface water or water containing salt is not permis-
sible. Your local water utility can provide you with general infor-
mation regarding the possible use of ground water. Water anal-
yses are carried out by specially-equipped laboratories.
Irrespective of any legal regulations, a water analysis must be
carried out to establish conclusively whether the ground water
is compatible for the evaporator of a heat pump (see table).
If one characteristic is negative “-” or two characteristics are
“0”, the water quality is not sufficient for the heat pump.
If the necessary water quality is not achieved or if this cannot be
guaranteed long-term, we recommended installing a brine-to-
water heat pump equipped with an intermediate circuit.
Table:
Resistance of copper-soldered stainless steel plate heat ex-
changers to substances contained in the water
+
Normally good resistance
0 Corrosion problems can arise,
particularly if several factors receive an evaluation of “0”
- Should not be used
[<: less than, >: greater than]
Evaluation characteristic
Approximate
concentration
range (mg/l)
Evaluation of
the copper
Substances that can settle (org.) 0
Ammonia NH
3
< 2
2 to 20
> 20
+
0
-
Chloride < 300
> 300
+
0
Electrical conductivity < 10  S/cm
10 to 500  S/cm
> 500  S/cm
0
+
-
Iron (Fe), dissolved < 0.2
> 0.2
+
0
Free (aggr.) carbonic acid < 5
5 to 20
> 20
+
0
-
Manganese (Mn), dissolved < 0.1
> 0.1
+
0
Nitrate (NO
3
), dissolved < 100
> 100
+
0
PH value < 7.5
7.5 to 9
> 9
0
+
0
Oxygen < 2
> 2
+
0
Hydrogen sulphide (H
2
S) < 0.05
> 0.05
+
-
HCO
3
-/SO
4
2
-
> 1
< 1
+
0
Hydrogen carbonate (HCO
3
-) < 70
70 to 300
> 300
0
+
0
Aluminium (Al), dissolved < 0.2
> 0.2
+
0
Sulphate < 70
70 to 300
> 300
+
0
-
Sulphite (SO
3
), free
< 1 +
Chlorine gas (Cl
2
) < 1
1 to 5
> 5
+
0
-