Alde Compact 3030 Installationsanleitung Seite 51

10. Filling the heating system
The system must be filled with a mixture consisting of distilled water and glycol.
We recommend using a high quality premixed glycol (with inhibitors) intended for aluminium heating
systems. When using concentrated glycol, the mixture must consist of 60% distilled water, or water
with no salt content and 40% glycol.
If the system is exposed to temperatures lower than -25°C, the glycol content must be increased,
but must not exceed 50%. The glycol mixture must be changed every two years, as properties such
as corrosion protection degrade.
If Alde Premium Antifreeze is used, the replacement period can be extended to max. 5 years under
normal use.
We recommend filling the glycol system using Alde's service pump, which fills and vents the system.
The level should be approx. 1 cm over the Min. line when the heating system is cold. (See Fig. 23)
In the case of dual zones, vent both zones n the system after filling.
Add more glycol if the glycol level drops during venting. Vent a newly-filled heating system regularly.
10.1 Ventilation of the heating system
When filling glycol mixture into the system, air pockets may form, depending on how the piping system
is installed.
A lack of heating in the vehicle or when only the first few metres of the pipes extending from the boiler
are warm even though the circulation pump is running, are signs of air in the system.
Fig. 23, Expansion vessel
Vent as follows:
1. Boiler must be switched off
2. If the boiler is equipped with a vent screw on the output pipe: open the screw and leave it open
until fluid comes out. Proceed to item 4.
3. If the boiler is fitted with automatic vents, venting will be performed automatically. Start the boiler
and let the fluid circulate in the system until it is vented. Top up with fluid if necessary in accord-
ance with item 5. If this does not help, turn off the boiler and go to item 4.
4. Open the other vent screws in the system one by one. Leave them open until glycol mixture
comes out of them, then close them.
5. Check fluid level in the expansion tank. Top up if the level has dropped after ventilation. The fluid
level in the expansion tank must lie 1 cm above the min. line (Fig. 23) when the system is cold.
6. Start the boiler and allow it to run for a while. Feel whether the pipes and convectors around the
vehicle are getting warm. If they are hot, venting is complete, otherwise proceed to point 7.
7. Put the pump (pumps in a dual-zone system), in speed position 5. Turn off electricity and gas.
Set the heat to 30 °C and let the boiler run for 5 minutes. If underfloor heating with a separate
pump is installed, do not forget to turn its pump to position 5 as well. Then set the underfloor
heating to continuous operation. Next ,begin again at item 1.
8. Do not forget to reset the pan to normal speed after venting; usually position 2.
Fluid level in a cold system
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