WATERKOTTE EcoTouch DS 5027 Ai, Planning And Installation Manual

Page: 30 / 60

Installation and connection
2005/06/10
30 / 60
Copyright

2013 by: WATERKOTTE GmbH. Subject to changes.
7.3.4 Flow monitoring
When using water as heat source, the evaporator of the heat pump can be
destroyed by ice formation due to lack of water (frost damage). Repeated
switching on of heat pump in an improper forced manner may easily result
in total loss. For this reason, we specify a reliable protective measure
against lack of water.
The protective measure consists of two devices that function independently
of one another:
a) Temperature limit by controller: For this purpose, the controller is config-
ured for operating mode "Heat source water" This solution allows that:

a warning is generated if value drops below +1 °C and

operation is interrupted when value drops below -1 °C.
b) Because the measure mentioned under a) cannot react quick enough in
case of sudden lack of water, an additional low water safety device must
be provided.
A low water safety device consists of a float-type volume display with ad-
justable limit indicator (limit indicator is a Reed contact).
Function:
The heat pump control switches the compressor on with a time delay to
"pump heat source". The start of the compressor is only enabled if the min-
imum water volume is present during the lead time and the limit indicator
did not respond. This device remains active during the entire operation of
the heat pump. If water volume drops below the permissible level during
operation, the heat pump is shut down. This device provides maximum se-
curity because it virtually covers all risks, such as filter contamination, evap-
orator contamination, overloaded well, etc.
Damages caused by freezing of evaporator result in exclusion of warranty!
7.3.4.1 Filter
To prevent contamination, the media inlets of the evaporator and heat ex-
changer must be equipped with a filter (0.8 mm mesh). Contamination in
the heat exchanger can cause corrosion and - in some applications - freez-
ing of the heat exchanger!
7.3.4.2 Cleaning
If the formation of deposits is to be expected (e.g. severe contamination)
based on water quality, cleaning must be performed in regular intervals.
Cleaning can be performed by flushing. The plate heat exchanger is to be
flushed with a suitable cleaning agent in counter-flow direction.
If chemicals are used for cleaning, please ensure that they are compatible
with stainless steel or copper. Failure to comply can result in destruction of
plate heat exchanger!