TAC AB, Feb 2000
4:9
Special functions, P:16 -
TAC 200 User’s Manual
4.7 Night setback and Morning boost
TAC 200 uses a night SP during the night time operation.
The actual SP value depends on several factors.
If there is a room sensor, without a SP dial, EGRL:
P:06 Setpoint room, night (used as SP
room
)
If there is a room sensor, with a SP dial, EGF1:
P:07 Night setback SP (affecting the SP
room
)
(A positive value means raising the night temperature.)
If there is no room sensor:
P:07 Night setback SP (affecting the SP
supply
)
To summarise:
Application SP
day
SP
night
EGRL P:05 P:06
EGF1 SP-dial SP-dial adjusted with P:07
No sensor SP
supply
SP
supply
adjusted with P:07
The SP value is also affected by the variable Night setback and the
Morning boost.
The Night setback of the supply temperature varies to ensure that the
heating system will be able to reach the correct room temperature even
after nights with low outdoor temperatures.
The magnitude of the setback is determined via a curve with two variable
outdoor temperatures, P:38 and P:39, see figure on the next page.
These two outdoor temperatures are also used to determine the Morning boost.
A certain time before time program 1 will indicate Day time operation, the
controller boosts the supply temperature.
The boost varies with the outdoor temperatures. It reaches its maximum at the
P:38 temperature and is reduced to zero at 20°C and at the P:39 temperature
(where there is no longer any night setback), please refer to the figure.