Emicon EAH Use and maintenance manual - page 28
Use and Maintenance Manual Air-cooled water chillers and Heat Pumps R-PAE/R-PAH/EAH
Rev. 1 del 03/09
4.5.2
Use of anti-freeze mixtures
In case an anti-freeze mixture is used, it is necessary to follow some precautionary measures:
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The temperatures shown in the above table are approximate. Sometimes suppliers dilute the product and
therefore it is necessary to follow the dilution percentage recommended by the anti-freeze liquid
manufacturer.
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Do not release the anti-freeze solution in the environment, but deliver it to an authorized waste disposal
facility.
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Make sure the anti-freeze fluid used is compatible with the system materials.
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If we increase the anti-freeze quantity we get a higher anti-freeze protection, but as a consequence the
solution will become denser (and more viscose when cold), thus overloading uselessly the circulating pump
and thus reducing the unit performance.
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Do not use anti-freeze substances such as chloride or other products that might cause electrogalvanic
corrosion.
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Change the anti-freeze solution every two years.
The inhibited monoethylene glycol is harmful if ingested and can cause irritation if on contact
with skin and sensitive mucous membranes. Therefore, it is recommended to wear protection
glasses and gauntlets and to avoid the contact with the mouth; follow the safety instructions
indicated on the container or in the corresponding directions.
4.5.3 Hydraulic circuit filling
Once the hydraulic circuit and the unit connection are performed, it is necessary to fill the circuit.
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Open all the air discharge valves on the circuit.
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Connect the circuit to a water supply system, possibly in a permanent way, by means of an automatic fill group
provided with a manometer and a non-return valve.
If the circuit works with an anti-freeze mixture, fill the circuit with an appropriate quantity of pure anti-
freeze fluid according to the system size and to the anti-freeze concentration to get.
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Start filling the system with water;
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Check all the air discharge valves present on the system and shut them when water, instead of air, starts to go out.
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Once all valves are closed, go on filling the system with water until a pressure between 1,5 and 3,5 bar is reached.
In case filling is done manually, stop the water charge and start the circulating pumps so that any presence of air can
be gathered in the top points where air discharge valves are present. After two operating hours, stop the pumps and
discharge the air by means of the air discharge valves. Charge more water to bring pressure back to its orginal
value. Repeat the operation until no air goes out from the air discharge valves.
Make sure the water pressure in the system always ranges between 1,5 and 3,5 bar.
After the leak test with water is performed, if low ambient temperatures or a long break before the
startup are likely, it is recommended to drain the circuit or to fill it with an anti-freeze mixture. The
draining must be particularly accurate in case free-cooling coils are installed.
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