7065 - Supply of Cooling System Glycol & Corrosion Inhibitor, 3.Specifications (2)Status: Approved Confidential Document id: DBAE138291 - Page 4 (4)
Page
4 (4)
Document No
4V92A0765
Rev
m
The stricter raw water quality requirements compared to what is specified when cooling water additives are
used shall be taken into account, see page 1. Due to a severe corrosion risk WWCU can´t be used in the
cooling water systems containing aluminium or aluminium alloys as a construction material. More information
can also be found from the document DAAF017522.
The WWCU can be a sensible alternative for the installations in which environmentally friendly solutions are
appreciated.
The assembly, installation, operation and maintenance instructions of Wärtsilä shall always be
followed. The contact details are included in the following table.
Distributor Manufacturer Treatment system
Wärtsilä Finland Oyj
Services
Tarhaajantie 2
FI-65380 Vaasa
Finland
Enwa AS
PO Box 257 Forus
N-4066 Stavanger
Norway
Wärtsilä Water Conditioner
Unit (WWCU)
USE OF GLYCOL
If a freezing risk exists, glycol needs to be added to cooling water. Since glycol alone does not protect
the engine and cooling water system against corrosion, additionally a validated cooling water additive
must always be used. All validated cooling water additives are compatible with glycol.
Ready-to-use mixtures containing both glycol and corrosion inhibitors are not allowed to use, since
those are normally designed to be used as strong (30 –) 50% / 50% mixtures. However, in Wärtsilä
engines normally a much lower glycol amount is adequate to protect the cooling water system against
freezing. But when decreasing the glycol amount, simultaneously also the concentration of corrosion
inhibitors will decrease to too low level resulting in an increased risk of corrosion.
The amount of glycol in closed cooling water system shall always be minimized since heat transfer of
water containing glycol has deteriorated significantly. The engine may therefore be subject to
additional output derating when using glycol in the cooling water, see document DAAE062266 for
more information.
There are commercially available two types glycol qualities, monopropylene glycol (MPG) and
monoethyleneglycol (MEG). So called industrial qualities of both glycol types can be used, but MPG
is considered to be a more environmental alternative.