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

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Manual - Solar hot water systems 0020009607_02 14
4.3 Solar pump
The solar pump unit is equipped with a three-speed solar
pump (Fig. 4.9, pos.
8 ) for the optimum adaptation of
the required circulating volume and the pump capacity
in the solar circuit.
Select the pump capacity, depending on the solar system
(e. g. collector surface, pipe diameter, length of the solar
circuit), so that the actual flow rate is slightly higher
than the nominal flow rate. The flow rate meter (Fig. 4.9,
pos.
7 ) is used for fine adjustment of the flow rate.
Observe the notes in Section 6.2, Setting the flow rate
and pump.
4.4 Thermal cut out of the solar pump
In order to comply with the requirements for unvented
hot water storage systems (G3) the power supply to the
solar pumps(s) must be taken via a manually resetable
temperature cut off on the hot water cylinder.
The Vaillant auroSTOR cylinder has such as device facto-
ry fitted, and this is wired in series with the power supp-
ly to the solar pump.
h
Note
If an East - West system is being installed then
the installation of a relay (to allow independant
operation of each pump) may be necessary.
1
3
A
B
C
D A
B
C
D
3
3
Fig. 4.10 Connection diagram of the solar pump TCO
The solar pump is secured by its own thermal cut out
(TCO) (
1 ) which is mounted on the solar cylinder (pre-
assembled at the factory for the VIH S GB 250 and
300 S). The power supply to the pump is interrupted at
cylinder temperatures higher than 90 °C.
4.5 Flow rate meter
0,
5
1 2 3
0,
5
1
2 3
4
5 6
4 5
6
L/
min
L/
min
1,1 l/min
1
2
Fig. 4.11 Flow rate meter 0 - 6 l/min
The flow rate meter (pos. 7 , Fig. 4.6) installed in the
return pipe is an essential component of the solar
system. To achieve optimum heat transfer, you must
achieve a certain flow rate, which is referred to as the
nominal flow rate (refer to Section 6.2, Setting the flow
rate and pump).
Upper deviations are not as serious as lower deviations.
Make the rough adjustments with the solar pump first.
You can make the fine adjustments with the adjustment
valve (
1 ) of the flow rate meter. You can view the set
value on the display ( 2 ) of the flow rate meter.
The flow rate meter has a fill/vent valve for filling and
draining the solar circuit.
h Note
Do not under any circumstances set the flow
rate below the calculated flow rate. The
collector efficiency will be considerably reduced.
4.6 Solar fluid
4.6.1 Properties of the solar fluid
This information applies to Vaillant solar fluid (20 l
canister: item no. 302 429).
Vaillant solar fluid is a ready-mixed antifreeze and
anticorrosive, consisting of approximately 45%
propylene glycol with anti-corrosion inhibitors and 55%
water. It is resistant to high temperatures and can be
used both with Vaillant tube collectors and Vaillant flat
plate collectors.
Furthermore the solar fluid has a high thermal capacity.
The inhibitors provide reliable corrosion prevention
when using different types of metal (mixed installations).
4 Description of the components