Filling The Heating System; Bleeding The System - Alde Compact 3020 HE Installation Instructions Manual

5:13 FILLING THE HEATING SYSTEM

The heating system must be filled with a fluid mixture consisting of distilled water and ethylene glycol. For best re-
sults, use high-quality ready-mixed ethylene glycol (with inhibitors) intended for use in aluminium heating systems.
The proportions when using concentrated ethylene glycol are 60% distilled water, or water that is free of salts, and
40% ethylene glycol. If the heating system will be exposed to temperatures below -25°C, the ethylene glycol content
has to be increased, however, do not exceed 50%. The ethylene glycol mixture has to be changed every other year,
since properties such as corrosion protection, deteriorate over time. If Alde Premium Antifreeze is used, the interval for
changing the mixture can be extended to max 5 years under normal operating conditions.
The ethylene glycol system is topped up in the expansion tank. Either manually or using Alde filling pump, which both
fills and vents the system. During manual filling, pour the ethylene glycol mixture slowly into the expansion tank. When
the heating system is cold, the level should be approx. 1 cm above the MIN line.
Bleed the system. Top up with more fluid if the level falls during bleeding. In newly filled heating systems, bleed at
regular intervals.

5:14 BLEEDING THE SYSTEM.

Depending on how the pipes have been fitted, air pockets may form when the system is filled with ethylene glycol fluid.
If the pipes only warm up a metre or so from the boiler, even though the circulation pump is operating, this is a symp-
tom of air trapped in the system.
Bleed as follows:
1. The boiler has to be switched off.
2. If a bleed screw is fitted to the outgoing pipe of the boiler, open this bleed screw and leave it open until fluid starts
coming out. Then, go to point 4.
3. If the boiler is equipped with an automatic air vent, bleeding the boiler takes place automatically. Start the boiler
and circulate the fluid in the system until it is vented, top-up with fluid, if needed, according to point 5. If this
doesn't help, switch off the boiler and go to point 4.
4. Open the other bleed screws in the system, one by one. Leave the bleed screws open until ethylene glycol fluid
starts coming out of them, and then close them.
5. Check the fluid level. Top-up if the level has fallen during venting, the fluid level in the expansion tank has to be
approx. 1 cm above the min line in a cold heating system.
6. Start the boiler and let it run for a while. Feel if the pipes and radiators are heating up around the vehicle.
If this does not help, use an Alde filling pump..
NOTICE
• Be sure that the heating system has been thoroughly bled. If this is not the case, there may be a risk of overheating.
• Never use full electric or gas capacity before the system has been thoroughly bled. There may be a risk of
overheating.
NOTICE
The boiler must not be started if the level of ethylene glycol fluid
is too low in the heating system.
Liquid level in a
cold system
NOTICE
Vessels used for handling or mixing the liquid must be spotless-
ly clean. This is to prevent the growth of bacteria and corrosion
in the system.
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