Danfoss EFIT 850, Инструкция по установке и эксплуатации, Страница: 34 / 36

34
User Manual
Post-heating
If the reason for ending a heating period is a decrease of moisture to below the chosen
level, the post-heating period will start . Post-heating ensures that no ice and snow is
left on the roof .
If system priority is low, heating might be paused at any time!
The ground system uses heated sensors which under normal circumstances
will hold a temperature of 1 .5°C . In connection with measuring the area temperature
heating of the sensor is turned off for 90 minutes at a time . This is done in order to ob-
tain a correct measurement of area temperature which is not influenced by sensor tem-
perature . If a system only has one sensor this sensor is constantly heated for 90 minutes
and then turned off for 90 minutes . This entails that measurement of temperature can
be up to 3 hours delayed . With more than one sensor this performance is significantly
improved .
Security and energy consumption
High security – higher energy consumption
If a high degree of security against ice and snow is wanted, make the following adjust-
ments of the operation parameters:
• Increase the standby temperature
• Increase the melting temperature
• Decrease the moisture level (close to setting 5)
• Prolong the post-heat period
This will give a high degree of security in even dry areas .
Low security – lower energy consumption
Conversely, low energy consumption and a moderate level of security against ice and
snow could be prioritized . In this case make the following adjustments of the operation
parameters:
• Decrease the standby temperature
• Decrease the melting temperature
• Increase the moisture level
• Shorten the post-heat period
This will give relatively low energy consumption, but the area may remain wet and icy
in short periods .
The factory settings are average values providing a relatively high degree of
security and moderate energy consumption .
Appendix B