Xylem EPR IM Electric heater-circulator unit EPR (obsolete) - Manual (Page 13)

13
Instruction manual Laing Electric heater circulator unit
www.lainginc.com
sensor C and switches off the circulator of the Electric heater circulator unit
if this temperature exceeds the set temperature. This ensures that - indepen-
dent of the function of the control – overheating of the floor heating pipes is
avoided.
Program selection for the switching sequence of the heating elements
The Electric heater circulator unit has three heating elements, each of which
has its own solid state relay. If heat is required, it is normally neither desired
nor necessary that all heating elements are switched on simultaneously.
While this would load all three phases fully, the activation of all three heating
elements could cause overheating at times of off-peak heat demand.
Therefore, several methods can be selected by which the heating ele-
ments
will not be switched on at the same time, but staged over time. Moving the
first jumper between the pins 1 to 4 will perform this task. However, only one
of these jumpers should be closed at any time. If by mistake several jumpers
have been installed, the red and yellow LEDs start blinking and the unit will
not operate.
An overall view of the jumper settings for the switching sequence can be
found on the second to last page of this manual.
A The heating elements will always be switched on simultaneously. This kind
of function can be used with all temperature control methods. If the utility
company does not allow the switching of individual heating elements, this
function must be selected. The disadvantage is that all heating elements
are activated simultaneously and that all three phases are fully loaded even
if the heat requirement is low. If the heat requirement is low, this method
can also lead to overtemperature. To select this function, jumper 1 must
be closed and jumpers , 3 and 4 must be open.
B The heating elements are activated depending on the temperature. This
function is only applicable in combination with the integrated constant
temperature control and with room temperature guided control which uses
the constant temperature function.
This function cannot be used with an outside temperature guided control or
another remote control that regulates the feed temperature of the Electric
heater circulator unit.
When the feed temperature is K below the set temperature of the con-
stant temperature control, the first heating element is switched on. If the
temperature drops another 3K, the second heating element is activated.