Maintenance - Danfoss VX Solo HWS Instructions For Installation And Use Manual

Instructions for installation and use

12.0 Maintenance

Maintenance work
Is only to be carried out by qualified and authorised personnel.
Inspection
The substation should be checked regularly by authorised personnel.
Any necessary maintenance must be performed in accordance with the
instructions in this manual and other sets of instructions.
During service the dirt strainers are to be cleaned – including the filter
on the controller, all pipe connections must be tightened and the safety
valve must be function tested by turning the lever.
Rinsing/cleaning of plate heat exchanger
To clean the plate heat exchanger, rinse it by running clean water
through the exchanger at high speed and in the opposite direction to
the normal flow. This will remove any dirt deposits that may have built
up in the exchanger. If rinsing with clean water is not sufficient, the
exchanger can also be cleaned by circulating a cleaning agent approved
by Danfoss (e.g. Kaloxi or Radiner Fl cleaning fluid) through the
exchanger. Both these cleaning fluids are environmentally friendly and
can be disposed off through the standard sewer system. After use of
a cleaning fluid, the plate heat exchanger must be rinsed thoroughly
with clean water.
Acid cleaning of plate heat exchanger
Deposits of limescale may build up in plate heat exchangers for domestic
hot water on account of the large temperature fluctuations, and because
aerated water is used on the secondary side. If it becomes necessary
to clean the exchanger with acid, this can be done as shown on the
drawing to the right. Brazed plate heat exchangers can withstand
rinsing with a dilute acid solution - e.g. 5% formic, acetic or phosphoric
acid).
Measures after maintenance work
After maintenance work and before commissioning:
– Check that all screwed connections are tight.
– Check that all safety features, covers, that were removed, have been
replaced properly.
– Clean the working area and remove any spilled materials.
– Clear all tools, materials and other equipment from the working area.
– Connect to energy supply and check for leaks.
– Vent the system.
– Carry out any necessary adjustment again.
– Make sure that all safety features on the device and the system work
properly.
Meter reading
The caretaker/owner must perform visual checking and reading of
the energy meter at short, regular intervals.
Service procedures must only be performed by trained, authorised
personnel.
NB! Excessive consumption for whatever reason is not covered by
the Danfoss warranty.
Cooling / Return temperature reading
Cooling – i.e. the difference between the supply and return temperature
of the district heating water – has a significant effect on overall energy
economy. Therefore, it is important to focus on the supply and return
temperature in the heating system. The difference should typically be
30–35°C. Please note that a low district heating return temperature is
directly related to the return temperature from the heating circuit and
the return temperature of the circulation water.
It is therefore important to focus on these return temperatures.
Danfoss District Energy
VX Solo HWS substations
VI.HE.M1.02
17 17
DKDHR