To Protect The Water Circuit Against Freezing - Daikin EWYA004D2V3P Installer's Reference Manual

8.2.4 To protect the water circuit against freezing

About freeze protection
Freeze protection by glycol
EWAA004~008D + EWYA004~008D
Packaged air-cooled water chillers
and packaged air to water heat pumps
4P688013-1B – 2022.09
NOTICE
For service purposes, it is recommended to also install a shut-off valve and drain
point to the water OUT connection. This shut-off valve and drain point are field
supplied.
NOTICE
Install air purge valves at all local high points.
Frost can damage the system. To prevent the hydraulic components from freezing,
the software is equipped with special frost protection functions, that include the
activation of pump in case of low temperatures:
▪ Water pipe freeze prevention (see
▪ Drain prevention. Only applicable when Bivalent is enabled ([C‑02]=1). This
function prevents the opening of freeze protection valves in the water piping to
the outdoor unit when the auxiliary boiler is running at negative outdoor
temperatures.
However, in case of a power failure, these functions cannot guarantee protection.
Do one of the following to protect the water circuit against freezing:
▪ Add glycol to the water. Glycol lowers the freezing point of the water.
▪ Install freeze protection valves. Freeze protection valves drain the water from
the system before it can freeze. Insulate the freeze protection valves in a similar
way as the water piping, but do NOT insulate the inlet and outlet (release) of
these valves.
NOTICE
If you add glycol to the water, do NOT install freeze protection valves. Possible
consequence: Glycol leaking out of the freeze protection valves.
NOTICE
If you add glycol to the water, you also need to install a flow switch (EKFLSW2).
About freeze protection by glycol
Adding glycol to the water lowers the freezing point of water.
WARNING
Ethylene glycol is toxic.
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"Water pipe freeze prevention" [
Piping installation
4
165]),
Installer reference guide
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