Xylem EPR IM Electric heater-circulator unit EPR (obsolete) User Manual
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Instruction manual Laing Electric heater circulator unit
www.lainginc.com
Another 3K lower, the third heating element is turned on. All heating ele-
ments stay on until the set temperature has been reached.
To select this function, the second jumper must be closed and jumpers 1,
3 and 4 must be open.
This control method has been implemented since it is customary in some
countries. If permitted, control function D is normally preferable.
C The heating elements are activated one after another. This control function
is applicable to all temperature control applications and should always be
used when the feed line temperature is controlled by a remote control,
for instance by an outside temperature guided control, or when the utility
company does not require that all phases are switched on at the same
time. In this case, this method guarantees the highest degree of heating
comfort. When the control detects that heat is needed, first one heating
element is switched on, after two minutes the second, and after another
two minutes the third.
To select this function, jumper 3 must be closed, jumpers 1, and 4 must
be open.
D The heating elements are activated depending on the heat load. This con-
trol function is recommended in combination with the integrated constant
temperature control, and also with a room temperature guided control,
since this also uses the constant temperature function. This function cannot
be used in combination with an outside temperature guided control that
controls the feed line temperature of the Electric heater circulator unit.
When heat is required, the first heating element is activated. After a sta-
bilizing time of approximately one minute, the control checks whether the
temperature is increasing or decreasing. If the temperature is increasing,
no further heating elements will be switched on. If the temperature is still
decreasing, the second heating element is turned on. After another minute,
the temperature change will be checked again, and if necessary, the third
heating element will be switched on. All activated heating elements will
stay on until the set temperature has been reached.
If the actual feed line temperature differs considerably from the set tempe-
rature (for instance when the heater is switched on), after approximately
one minute all heating elements will be turned on automatically.
To select this function, jumper 4 must be closed and jumpers 1, and 3
must be open.