its increasing temperatures, which may not be absorbed by the pipes of the city
network or the safety valve.
1.10 Freezing weather conditions
In the case freezing weather conditions, the SUN&HEAT closed-loop solar water
heater is automatically protected, provided that, during installation, the correct
solution of water and antifreeze (heat transfer fluid) was used (depending on the
installation site).
Besides the solar water heater, piping is also exposed to freezing weather
conditions. This concerns both pipes supplying cold water from the city network
and pipes transferring the domestic hot water. These pipes should be insulated.
In the case of frost, you should usually leave a light but steady flow of hot water
running from a hot water tap in the house to protect piping.
CAUTION
In the case of freezing weather conditions, use the back-up heating system
(electric resistance) only if you are sure there is a flow of water from the solar
system to taps in the house, which means that the water in the pipes has
not frozen. Otherwise, there is danger of destroying the storage tank (see
paragraph 1.9)
CAUTION
If, for some reason, there is a leakage in the closed loop of the solar water
heater and it is necessary to add heat transfer fluid, make sure you use the
proper proportion of water, antifreeze and corrosion inhibitor (see paragraph
2.1).
1.11 Summer holidays
During summer holidays and in other cases when hot water from the solar water
heater is not used, the water stored in the tank can reach very high temperatures
(up to 90
o
C - 95
o
C). The SUN&HEAT solar water heater is designed to withstand
these high temperatures. The owner of the system is not obliged to cover the
collector in such cases. It might be advisable to cover the collector, thus avoiding
the development of such high temperatures inside the storage tank.
