Vokera Unica Syphon\trap question

[PerryDigweed]

Should the syphon/trap always be full during normal operation?

i.e. does the syphon/trap fill first and then fill out through the condense pipe, or does the syphon/trap only fill up if the condense backs up and there's an overflow?

 

[GodKnows]

Same as your trap in a toilet, sink etc

 

[pontered]

trap is always full to stop fumes escaping, emptys like any s trap