Daikin EWAA016DAV3P - Page 71

8 | Piping installation
Installer reference guide
71
EWAA011~016DA + EWYA009~016DA
Packaged air-cooled water chillers
and packaged air to water heat pumps
4P620242-1 – 2020.06
NOTICE
Glycol absorbs water from its environment. Therefore do NOT add glycol that has
been exposed to air. Leaving the cap off the glycol container causes the
concentration of water to increase. The glycol concentration is then lower than
assumed. As a result, the hydraulic components might freeze up after all. Take
preventive actions to ensure a minimal exposure of the glycol to air.
Types of glycol
The following types of glycol are allowed:
▪ Ethylene glycol;
▪ Propylene glycol, including the necessary inhibitors, classified as Category III
according to EN1717.
Required concentration of glycol
The required concentration of glycol depends on the lowest expected outdoor
temperature, and on whether you want to protect the system from bursting or
from freezing. To prevent the system from freezing, more glycol is required.
Add glycol according to the table below.
Lowest expected outdoor
temperature
Prevent from bursting Prevent from freezing
–5°C 10% 15%
–10°C 15% 25%
–15°C 20% 35%
–20°C 25% —
–25°C 30% —
–30°C 35% —
INFORMATION
▪ Protection against bursting: the glycol will prevent the piping from bursting, but
NOT the liquid inside the piping from freezing.
▪ Protection against freezing: the glycol will prevent the liquid inside the piping
from freezing.
NOTICE
▪ The required concentration might differ depending on the type of glycol. ALWAYS
compare the requirements from the table above with the specifications provided
by the glycol manufacturer. If necessary, meet the requirements set by the glycol
manufacturer.
▪ The added concentration of glycol should NEVER exceed 35%.
▪ If the liquid in the system is frozen, the pump will NOT be able to start. Mind that
if you only prevent the system from bursting, the liquid inside might still freeze.
▪ When water is at standstill inside the system, the system is very likely to freeze
and get damaged.
Glycol and the maximum allowed water volume
Adding glycol to the water circuit reduces the maximum allowed water volume of
the system. For more information, see "Maximum water volume"[465].