Vaillant auroTHERM VFK 900, Руководство по запуску, обслуживанию и устранению неисправностей

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63 Manual - Solar hot water systems 0020009607_02
Malfunction Cause Remedy
Pump starts up and goes off shortly
afterwards.This is repeated several times
until the system runs its course. The same
occurs in the evening. The temperature difference of the controller
is too low or the pump speed is set too high.
The solar radiation is not yet sufficient to
heat up the entire pipework. Check whether the entire pipework is fully
insulated.Increase the temperature
difference of the controller.
The pump is making noises. 1. Air in the pump Bleed the pump.
2. Insufficient system pressure. Increase the system pressure.
Solar system
Clocking of the system. Incorrect position of the collector sensor Position the collector sensor in the flow.
Insulate the collector sensor.
The pressure gauge indicates a drop in
pressure. A drop in pressure is normal shortly after
filling the system, since air still escapes from
the system.If a pressure drop occurs again
later on, the cause may be an air bubble,
which has been subsequently released.
Furthermore there are fluctuations to the
pressure in normal operation mode between
0.2 to 0.3 bar, depending on the system
temperature. If the pressure drops
continuously, there is a leak in the solar
circuit, in particular in the collector array. First check all screw connections, stuffing
boxes at gate valves and threaded
connections, then the soldering points.
Check the collector array and replace a tube
or the collector if necessary.
The water pressure and amount of
discharged water decreases at hot water
taps. Pressure in the main cold water supply too
low. Inform the owner and notify the water
supply company.
Line strainer in the pressure limiting valve
dirty. Clean the line strainer in the pressure
limiting valve and replace it if necessary.
Pressure limiting valve defective. Replace the pressure limiting valve.
Blockage in the system. Unblock the blockage and replace any
blocked parts.
Check the system for water leaks at the
expansion relief valve and temperature/
pressure limiting valve.
The system is making noises. Normal in the
first few days after filling the system.
If it occurs later, there are two possible
causes: 1. The system pressure is too low. The pump
is drawing air via the bleeder.
Increase the system pressure.
2. Pump power set too high. Switch to a lower speed.
The solar gain is unusually low. The pipe insulation is too thin or incorrect.
The system may have been designed
incorrectly. Check the insulation. Check the layout of the
system (collector size, shading, pipe lengths)
and modify the system if necessary.
Solar control
auroMATIC 560: display example “KOL 1 Err“
or similar Defective sensor (short circuit or
interruption). 1. Check the cable connection.
2. Measure the resistance values of the
disconnected sensor at known
temperatures, and compare these with the
manufacturer's specifications.
3. Inspection of the piping for damage.
Solar cylinder
The cylinder cools down at night.
The flow and return temperatures vary after
switching off the pump. The collector
temperature is higher than the air
temperature at night. 1. The gravity brake is blocked. 1. Check the position of the blue handle.
2. Check the gravity brake for tightness
(jammed cuttings, particles of dirt in the
sealing face).
3. Do not connect the solar heat exchanger
directly, rather pull the supply pipes
downwards and then upwards to the
collector (syphon supports the gravity
brake) or install a 2-port valve, which is
switched on at the same time as the pump.
2. One-pipe circulation in the event of short
pipe networks with low pressure loss.
Install a gravity brake (as close as possible
to the cylinder).
Table 8.1 Troubleshooting (continuation)
Troubleshooting 8