Daikin EPRA08EAV3, Installer'S Reference Manual

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8 | Piping installation
Installer reference guide
91
EPRA08~W1 + ETVH/9W
Daikin Altherma 3 H MT F
4P634886-1 – 2021.03
NOTICE
Make sure both air purge valves (one on the magnetic filter and one on the backup
heater) are open.
All automatic air purge valves MUST remain open after commissioning.
8.2.6 To protect the water circuit against freezing
About freeze protection
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 "Water pipe freeze prevention" [
4
200]),
▪ 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.
Freeze protection by glycol
About freeze protection by glycol
Adding glycol to the water lowers the freezing point of water.
WARNING
Ethylene glycol is toxic.