Alde Compact 3020 PS Gebrauchsanweisung Seite 43

8.4 Bleeding the heating system
When filling the system with glycol mixture air pockets might be formed, depending on how the pipes
have been fitted. A sign
from the boiler, even though the circulation pump is running.
In a newly filled heating system small air bubbles might form in the expansion vessel, creating a gur-
gling sound. If the circulation pump is stopped for a few seconds the bubbles normally goes away. If
the problem persists, bleed the heating system.
WARNING
Scalding injuries
Keep in mind that the glycol mixture might be very hot.
NOTICE
Never open the bleeder screws while the pump is running, this will draw air into the system.
Bleed as follows
1. The boiler shall be turned off
2. If the boiler is equipped with a bleeder screw on outgoing pipe from the boiler: open the bleeder
screw and leave it open until liquid comes out. Proceed to item 4.
3. If the boiler is equipped with an automatic air bleeder, bleeding of the boiler is done automatically.
Start the boiler and allow the fluid to circulate in the system until thorougly bled. Top up with fluid when
needed according to item 5. If this does not help, turn off the boiler and continue to item 4.
4. Open the rest of the bleeder screws in the system one by one. Leave the bleeder screws open until
glycol mixture starts coming out, then close.
5. Check the fluid level in the expansion vessel. Top up if the level has dropped during bleeding. The
fluid level should be approx. 1 cm over the min-line (fig. 15) in a cold system.
6. Set the circulation pumps to max speed. Start the boiler and let it run for a while. Feel if the pipes
and convectors are heating up around the vehicle, then lower the circulation pumps again, otherwise
repeat the bleeding. If this does not help, contact Alde Service Partner.
7. Do not forget to lower the pumps to normal speed again (usually step 2), to avoid sounds and wear.
NOTICE Overheating
• Check that the heating system in thoroughly bled.
• Never use full electricity or gas capacity before the system is thoroughly bled.
Remedy for remaining air bubbles, single axle caravan
1. Stop the circulation pump.
2. Lower the front of the caravan as far as possible. Leave in this position for a few minutes, to allow
the air to travel upwards in the heating system.
3. Open the bleeder screw at the highest point. Leave it open until glycol mixture starts coming out.
4. Raise the front of the caravan as far as possible and repeat item 3.
5. Position the caravan horizontal position and start the circulation pump.
6. Check that the pipes and convectors around the vehicle are heating up.
Remedy for remaining air bubbles, motor home or twin-axle caravan
The easiest way to bleed the heating system is to place the vehicle on a sloping surface or to raise
one end of the vehicle using a jack. Bleed the heating system in inclination as described above for
single axle caravan. Alternatively, the heating system can be bled using an approved filling pump at a
workshop, contact Alde Service Partner.
that air pockets has been formed is that the pipes only warm up a metre or so
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