Fujitsu WATERSTAGE 112 Maintenance Document page 88

Heat Pump, Split System, Single Service, 3 phase
Dewpoint Monitoring
Line no. Programming line
946 Lock time dewpoint limiter
947 Flow temp setp incr hygro
948 Flow setp incr start at r.h.
950 Flow temp diff. dewpoint
These settings are useful only when a dewpoint
sensor (hygrostat). is used.
Lock time dewpoint limiter
As soon as the
condensation, it closes its contact and switches off
the cooling process. When the contact reopens the
"dewpoint sensor lock time" period begins. Cooling
will resume only after this time period has elapsed.
The dewpoint sensor must be assigned to input H2
as "Dewpoint sensor".
Flow temp setp incr hygro
To avoid condensation due to an excessively high
humidity level in the room, a fixed increase in flow
temperature can be obtained by means of a
hygrostat. As soon as the humidity exceeds the value
set on the hygrostat, the hygrostat closes its contact
and activates the flow temperature increase defined
here.
Flow temp diff. dewpoint
The relative humidity of the ambient air and the
corresponding room
compute the dewpoint temperature.
To prevent condensation forming on the surfaces, the
value adjustable on line 950 determines the lower
limit of the flow temperature above the dewpoint
temperature.
88
dewpoint sensor detects
Flow temp setpoint
increase
948
temperature are used
The hygrostat must be assigned to an Hx input as
"Flow temp setpoint increase by hygrostat".
Flow setp incr start at r.h.
To avoid condensation caused by an excessively
high humidity level in the room, a gradual increase in
flow temperature can be performed by means of a
humidity measurement 0... 10 V.
If the room's relative humidity exceeds the value
"Beginning of flow temp increase at relative humidity",
the flow setpoint is gradually increased. The increase
beginning (line 948) and the maximum increase (line
947) can be adjusted.
The humidity sensor must be assigned to an H2 input
as "room relative humidity 10V".
100%
This function can be deactivated with the setting - - - .
The humidity sensor must be assigned to an H2 input
as "Room relative humid. 10V" and a room
to
temperature sensor is required (input H2 as "Room
temperature 10V" or "room unit").
947
Relative
humidity
Maintenance Document 1394-1