Xylem EPR IM Electric heater-circulator unit EPR (obsolete) - Manual (Page 18)

18
Instruction manual Laing Electric heater circulator unit
www.lainginc.com
Outside temperature guided control
In connection with the outside temperature guided control AR 1000 d it is
possible to control the feed line temperature dependent upon the outside
temperature.In this case the switching terminal of the control unit must be
connected to the control input ot the Electric heater circulator unit and the
feed line sensor must be attached to the correct place at the top part of the
Electric heater circulator unit.(See also chapter “Installation of the feed line
sensor”).
The connection should be made according to the electrical diagram pro-
vided with the unit. The settings of the outside temperature guided control
should be taken from the relevant manual.
The constant temperature control is always active. The constant tempe-
rature has to be set at least as high as the highest temperature requested by
the outside temperature guided control.
Electrical Diagram AR 1000 d
Safety temperature limiter
In order to protect the Electric heater-circulator from overheating, it is equipped
with a safety temperature limiter, which in case of overheating separates one
side of the heating element permanently from the grid.
When the safety temperature limiter had been activated, it has to be reset
manually by pressing knob Z.
The safety temperature limiter reacts only when there is a malfunction in the
system. Therefore, as a first step, the malfunction that caused the activation
of the safety temperature limiter has to be corrected.
When the activation of the safety temperature limiter was caused by ope-
rating the Electric heater-circulator without water, it is possible that the safety
switch could be damaged permanently. In this case it is impossible to reset the
safety temperature limiter, it has to be replaced. (See chapter “Replacement
of the safety temperature limiter STBR”).