Lauda P 10 Operation Manual page 23

Operating the cooling coil in a central
cooling water system
Operating the cooling coil with drinking
water
V6
CAUTION!
Operation with cooling coil, discharge of hot steam/boiling
cooling water
Scalding
Only use the cooling coil up to a bath temperature of

95 °C.
The cooling coil is approved for PRO heating thermostats (bath thermostats
and circulation thermostats) operated on a central cooling water system up
to a bath temperature of 95 °C. In practice, the operating pressures in a
central cooling water system vary significantly and the return pipes are not
depressurized, which means that the cooling coil does not drain completely
when the cooling fluid supply is closed. If temperatures are higher than the
boiling point of the cooling water, the high degree of heat lost when the
cooling water evaporates in the cooling coil impairs the temperature process
enormously. Furthermore, the effect of possible bursts of steam on the
central cooling water circuit or connected consuming units should not be
underestimated.
WARNING!
Operation with cooling coil, hot steam bursts/hot steam at bath
temperatures above 95 °C
Scalding
The open end of the cooling coil hose must be secured to

the outlet.
The cooling coil is approved for PRO heating thermostats (bath thermostats
and circulation thermostats) operated on a drinking water pipeline with dep-
ressurized outlet up to a bath temperature of 155 °C. It is possible to operate
the cooling water valve safely with water on a PRO heating thermostat above
100 °C because the cooling water can drain from the cooling coil on the
heating thermostat and does not have to evaporate completely first. If the
cooling fluid supply opens and cooling water enters the cooling coil at a bath
temperature of more than 95 °C, it produces a brief burst of steam, which is
why the open end of the cooling coil hose must be secured to the outlet. The
hoses leading to and from the cooling coil must slope downwards all the way
to the outlet.
The cooling capacity of the bath cooling coil depends on the bath tem-
perature of the thermostat and the temperature of the cooling water. If oil
is used as heat transfer liquid instead of water under similar temperature
conditions, a slightly lower cooling capacity can be expected. If higher bath
temperatures (up to 155 °C) are reached during operation, the cooling
capacity increases because of the high thermal gradients between the heat
transfer liquid and cooling water.
PRO bath thermostats and circulation thermostats 23 / 156