Vaillant auroTHERM VFK 900, Start-Up, Maintenance And Troubleshooting Manual

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15 Manual - Solar hot water systems 0020009607_02
h
Note!
Do not use any other anti-freeze or inhibitors
with Vaillant solar collectors.
Only Vaillant solar fluid is approved.
a
Caution!
Risk of damage!
Vaillant solar fluid is ready mixed. You may not
under any circumstances mix it with water or
other fluids. Otherwise it will become
ineffective as an antifreeze or anticorrosive,
resulting in damage to collectors or other parts
of the system.
Vaillant solar fluid is infinitely durable in hermetically
sealed containers.
Skin contact is normally not dangerous. Eye contact only
causes minor irritations, you should nevertheless
immediately wash your eyes.
Observe the safety data sheet (refer to Section 4.6.4).
4.6.2 Protection of the solar circuit against frost
and corrosion
To protect the solar system reliably against frost in
winter, the entire solar circuit must be filled 100 % with
solar fluid (item no. 302429).
h Note!
You can achieve frost resistance of about
-28 °C by filling the solar system with Vaillant
solar fluid.
No damage is caused by frost even at outside
temperatures below -28 °C, since the expansive
effect of the water is reduced. Check the
antifreeze effect after filling the system and
then once a year.
Component Volume (l)
VIH S GB 200 S heat exchanger solar circuit 4.12
VIH S GB 250 S heat exchanger solar circuit 4.12
VIH S GB 300 S heat exchanger solar circuit 4.4
VIH S GB 200 S heat exchanger reheating circuit 3.7
VIH S GB 250 S heat exchanger reheating circuit 3.7
VIH S GB 300 S heat exchanger reheating circuit 3.7
Solar pump unit 0.9
auroTHERM exclusive VTK 570 0,8
auroTHERM VFK 900 1,1
auroTHERM classic VFK 990/1 1,1
Protection vessel 5, 12 or 18 l
Table 4.3 Volume of the individual components
Pipe diameter Pipeline volume (l/m)
15 mm 0.18
18 mm 0.20
22 mm 0.31
28 mm 0.50
flexible pipe DN 12 mm 0.15
flexible pipe DN 16 mm 0.27
flexible pipe DN 20 mm 0.36
Table 4.4 Pipeline volume
Proceed as follows to check the solar fluid; refer to the
operating manual of the solar fluid tester
(item no. 0020020155):
• Suck in the amount of fluid for the float to freely float
without sticking at the top with the suction ball of the
solar fluid tester (item no. 0020020645).
• View the density on the scale. The density must be
greater than 1.05 g/cm 3 . You must otherwise replace
the solar fluid.
• Measure the pH value with a pH value measuring strip.
You must replace the solar fluid if the pH value is
below 7.5.
1
2
3
4
5
6
Fig. 4.12 Solar fluid tester
Key
1 Transport case
2 Areometer
3 Thermometer
4 pH indicator rod
5 Standing
cylinder
6 Operating manual
a Caution!
Risk of damage!
Use only the original Vaillant solar fluid tester
(item no. 0020020645). Otherwise an
incorrect antifreeze value may be indicated.
4.6.3 Frost protection of the bivalent solar cylinder
You must drain the solar cylinder completely if it is to be
shut down in a room prone to frost. It is drained at the
cold water inlet with a T-piece with tap to be provided by
the installer.
Description of the components 4